Consciousness (chapter 6) Flashcards

Question

What would a lack of self awareness do?

Answer 1

Would compromise your ability to override potentially dangerous behaviours governed by impulses or automatic processing. Without the capacity to reflect, you might lash out after every provocation. Without the safety net of consciousness, sleepwalkers may fall down the stairs or have cooked foods and then burned themselves severely while grabbing red-hot pans.

Answer 2

It simply describes a neurological state that correlates with a particular state of consciousness, or one that directly generates consciousness. This idea is also enriched and supported by a number of philosophers including Dennett. Neurons and synaptic connections form very quickly and increase in number after birth to a maximum number at about 6 months of age. From this point on, synaptic pruning takes place where unused connections are removed, leaving only those that are needed.

Answer 3

Came from Edelman (1987) and explains how the brain loses the weakest or least used connections, and retains the strongest and most useful. Hence the Darwinian 'survival of the fittest' analogy

Answer 4

One pathway, extending from the primary visual cortex to the parietal lobe, carries information to support the unconscious guidance of movements. A second pathway, extending from the primary visual cortex to the temporal lobe, carries information to support the conscious recognition of objects.

Answer 5

Some have explored conscious perceptions that are created when specific brain areas are electrically stimulated, while others have tried to determine how consciousness is lost when patients are put under anaesthesia. Still others have used a procedure called masking to control whether people perceive a stimulus consciously or unconsciously. In experiments, participants undergo brain imaging while exposed to masked and unmasked stimuli. This enables scientists to assess how brain activity differs depending on whether the same stimuli (e.g. photographs of angry faces) are consciously or unconsciously perceived

Answer 6

They are processed consciously and unconsciously through different neural pathways. The pathway that produces conscious recognition involves the prefrontal cortex and several other brain regions that are bypassed in the pathway for unconscious processing

Answer 7

Scanning, for instance, is allowing us to see things happening in the brain in a way not thought of previously. However, it is extremely tempting to infer that people are thinking of an 'experience' when we can see that a stimulus generates a patch of activity in the brain, but conscious experience is more than a localised area of stimulation, so beware. Careful investigation can provide us with evidence that the person is experiencing a particular kind of experience. the scan allows us to infer things about general concepts, not the individual experiences themselves

Answer 8

There appears to be no single place in the brain that gives rise to consciousness. Instead, they view the mind as a collection of largely separate but interacting information-processing modules that perform tasks related to sensation, perception, memory, movement, planning, problem-solving, emotion and so on. The modules process information in parallel - that is, simultaneously and largely independently. However, there also is cross-talk between them, as when the output from one module is carried by neural circuits to provide input for another module. E.g. a formula recalled from memory can become input for problem-solving modules that allow you to compute answers during a mathematics examination

Answer 9

It represents the unified activity of multiple modules in different areas of the brain. In essence, of the many brain modules and connecting circuits that are active at any instant a particular subset becomes joined in unified activity that is strong enough to become a conscious perception or thought. The specific modules and circuits that make up this dominant subset can vary as out brain responds to changing stimuli - sights, sounds, smells and so on - that compete for conscious attention Subjectively we experience consciousness as unitary, rather than a collection of modules and circuits. Many factors influence these modules and, in so doing, alter our consciousness

Answer 10

The basic premise is that consciousness is not something that just happens to us, it is something that we do. Let us consider 'perception'. The generally held view by science is that perception involves internal representations and that we interact with the world as guided by these. An 'enactive' explanation does not necessarily deny that there may be representations in the brain, but theorists such as Alva Noe say that our brains to not necessarily construct models based on what we perceive. Our perceptual world is an integration of the skills we have developed. Perception, then, is a skill, and ut depends on our actions and how we carry them out, how we enact them Consciousness in general can be considered in the same way. Whatever consciousness is, it is not something that happens to us, it is something that we ourselves do. In this way, the neural basis of consciousness can be questioned and given another dimension. It is not the brain that provides us with consciousness; it is our actions and our behaviour that generates our consciousness

Answer 11

The process of concentrating on some feature(s) of the environment to the possible exclusion of others

Answer 12

The ability to respond to specific stimuli

Answer 13

This phenomenon is manifest as the often dramatic result of focussing one's attention as shown in a busy party situation. The tinkle of ice in glasses and the mingling of laughter and chatter all make for an engaging time for everyone. We all know that listening in on one particular conversation among the many going on around us can be done. It is often made possible because one of those engaged in one of the private conversations mentions your name, not loudly, but at a normal conversation level. Your attention is immediately drawn to their discussion, switching your attention quickly to this new source. The phenomenon describes the ability to attend to one conversation among many, but also the almost immediate attention switch facilitated by the mentioning of a salient word, such as your own name

Answer 14

Whereby participants are presented with two different sources of information simultaneously. One source is presented to each ear. The task is to attend to one of these 'channels' of information, perhaps by repeating the message as it is presented in a shadowing procedure. Following this part of the task participants reported as much of the unattended, or unshadowed, message as possible

Answer 15

Participants are better able to report the unattended stream than if the situation is reversed. This is because we process speech in our left hemisphere, stimulated by material presented on the left. What was particularly interesting from the early dichotic listening work was the finding that certain aspects of the stimulus could be recalled. These include broad categorizations, such as whether the sound in the unattended stream was speech or non-speech and whether the speaker was male or female. These rather broad characteristics could be correctly recalled although the semantic detail and meaning of the unattended messages could not, This suggests that, in this case, some types of information were allowed through for processing, whereas others were possibly lost. This finding was the basis for the filter theories following.

Answer 16

It attempts to explain why some words are attended to and do grab our attention, as in the cocktail party effect, and some are not. He said that we maintain our attention by engaging a filter of some kind. This filter is an early filter, meaning that a decision about what to allow through is made at a very early stage e.g. vocal characteristics. There are some problems though. These early filter models are problematic as they do not explain how we switch our attention quickly when, for instance, we hear our name mentioned at the other side of the room. In order to do this we music have some kind of route into our attention that is not a conscious or deliberately placed filter as Broadbent describes

Answer 17

Information can be presented at a very low level, or very quickly so that we are not consciously aware of it. Words, or stimuli, presented consciously, on a screen can be followed almost immediately with, and so linked to, mild shocks. Subsequent presentation of the word without the shock generates a mild stress response, such as sweating of the palms. This sweat raises the conductivity of the palm, and so can be measured electronically as a galvanic skin response (GSR). When the stimulus is presented subliminally, measurements of GSR show that the stimulus has been perceived, but not consciously. Early filter models would not predict this as the filter to allow material through would need to be deliberately placed very early in the process, consciously allowing material through or not, as described in the previous section. there must be some form of route that is not governed by a consciously placed filter, or else why would we let through the subliminally presented word?

Answer 18

An alternative to early filter models is to hypothesize that the position of the filter is later in the attention process. They said that the filter, or the decision whether to 'select' the information for attention, is made not at the very start of the process, but just before the person responds. The problem with these models is that all material is processed until the very last point, where only a tiny fraction of it is used. This is a terrible wasteful view and can be criticised in terms of cognitive economy. Stretching limited resources like this only to waste a huge proportion of the material processed is wasteful and uneconomical.

Answer 19

To attenuate something is to reduce the effect or power of something. This model describes attention similarly. All material is processed from the point that it is received right up until a response is made. Treisman suggests that rather than blocking unattended material entirely, with a filter or an attention age of some kind, it is attenuated. This model allows for all information to be processed, but only the unattenuated material makes it through to conscious attention. In a noisy environment of a club or cocktail party, the material we wish to 'ignore' is attenuated, leaving the material we wish to attend to standing out, allowing us to focus upon it. It goes on to say that each of the competing 'streams' of information being processed can be attenuated differently, allowing for different levels of attention as desired. This allows an explanation of how some stimuli can 'grab' our attention and how we can quickly switch attention in different circumstances, by swiftly altering the attenuation levels in each 'stream'

Answer 20

Attention is finite. Attention can be thought of in terms of a bottle. the material we may wish to allow out of the bottle (so that we can attend to it) is restricted by the narrowing of the bottleneck. this bottleneck provides a capacity control system. Treisman's attenuation model says that the width of the neck is entirely flexible. When we want more information to come out of the bottle, we adjust the size of the neck accordingly.

Answer 21

Maintaining a focus of attention on a specific item even when faced with alternatives and distractions

Answer 22

Searching for a single in the crowd is facilitated by attending carefully to small parts of the crowd at a time, and 'sweeping' your attention across it, hopefully finding the face you are searching for. This is an example of an 'exhaustive' search where those faces, other than the one you are looking for, act as distractors. Searches where the target shares many of the features of the distractors are hard, but where the features are different the target 'pops out' of the background. this 'feature analysis' may explain how our attention is quickly, as if automatically, focused when we hear our name in a cocktail party, or when we see the face of a loved one among many others on a busy shopping street

Answer 23

A two stage process: first the whole scene is processed and the individual components of all items are dealt with. Those that clearly identify the item as not belonging to the target are rejected. Next, the remaining items are reassembled, or 'glued' together, and compared with material in memory that may help us identify the target successfully. Visual attention can now be thought of, in part, as allowing us to regenerate the information received to allow attention and processing of objects as internal representations.

Answer 24

Posner develops the idea of visual attention in his attentional spotlight, which says that once glued together and reconstructed internally, our internally represented visual world has spatial characteristics just like the world around us. Visual attention then shines a 'spotlight' onto the parts of the scene we wish to attend to

Answer 25

The material lit by the attentional spotlight can be zoomed in on, as if with a camera lens. A narrow spotlight beam mans we focus on only a small part of the representation, a wider beam means we take in more

Answer 26

The spotlight model and the zoom-lens modification suggest that attention focuses on locations rather than objects. However there is work to support and contradict this.

Answer 27

Practice makes perfect. It is reached when a task no longer requires conscious control e.g. riding a bike

Answer 28

Our memory processes are capacity limited. It has been said that automatic tasks are capacity free. they are not limited by memory or attention limitations and as such, a number of them can go on in parallel, in the background if you like, while we carry out other tasks. Controlled processes on the other hand are capacity limited and take place in series. That is to say, one at a time. Controlled processing is carefully under our conscious control and as such is flexible, dynamic and changeable. However, with very well-practiced and automatic task, changes are very hard to make. They become second nature. The most famous example is the Stroop test

Answer 29

The ability to respond, seemingly simultaneously, to multiple tasks or demands

Answer 30

A number of things, including how practised we are at them, and the nature of the tasks themselves

Answer 31

The more we rehearse, the better we get. Repeating tasks over and over encourages a move from controlled to automatic processing. Developing skills through practice reduces the errors on that task.

Answer 32

The difficulty of the tasks (dual task performance)influences performance. Two easy tasks combined will result in fewer errors than two difficult tasks. Difficulty, of course, is entirely subjective. Data-driven tasks are largely free of the demands of cognitive resources. Performance on them is limited by the amount of information we have to complete the task, not necessarily how skilled or clever we are. Where resources are limited we can improve performance by shifting them from one task to another. Removing the demands required to follow the narrative of a play by turning off the radio makes writing a tricky passage much easier.

Answer 33

The idea of similarity is related to the idea of modality in perception and attention. Tasks requiring auditory attention arrive at the auditory modality and are dealt with accordingly. Those requiring visual attention are similarly dealt with within the visual modality. If one of the tasks is visual and another is auditory, then they do not compete for the modality-specific resources. Similarly, if both require memory resources then they will compete for them, and the result may be reduced performance. Finally, if tasks require the same mode of output, perhaps fine motor skills as in sewing and watchmaking, then performance is likely to suffer as a result

Answer 34

Attention is drawn by an external stimulus, perhaps because it means we are required or needed to act in some way. Salient warning words or noises are similarly compelling. These might include the word 'FIRE' or the sound of a gunshot. In either case they elicit external or exogenous control over our attention.

Answer 35

The internal equivalent to exogenous control. It may be that we expect something to happen in a particular position and so we are primed to move our attention in that direction. E.g. the work or Posner (1980) where pps were cued to respond to the right or left of a fixation point with an arrow. The arrow provided a spatial cue within the environment, eliciting endogenous control of spatial attention to the left or right of the fixation point

Answer 36

Information from one modality (e.g. the lips) adds to information from another (e.g. the ears). The result is improved performance. Sometimes, when endogenous or exogenous cues draw our visual attention to one position or another, attention from another modality (touch or hearing) may also be drawn to the same position. The results can be startling and are best described with reference to the ventriloquist effect.

Answer 37

In ventriloquism the moving lips of the dummy act as an endogenous cue. Visual attention is drawn spatially to the position of the moving lips and the auditory information carrying localisation information about the origin of the voice are drawn to the same location. The effect is that we hear the voice of the ventriloquist as emanating from the moving lips of the dummy. In this case, auditory and visual attention is woven together in a truly multi-modal effect

Answer 38

A failure to notice an unexpected item in a visual scene.

Answer 39

A different, but closely related phenomenon to inattention bias where we fail to see if an item has changed in some way. Perhaps it is moved or an aspect of it is altered. Those that seek to trick us, usually in jest, use their not insignificant knowledge of attention direction and phenomena such as change blindness in their craft

Answer 40

AN ERP is recorded as a series of waves, recorded from a net of recording points on a person's skull. Research has looked at 2 peaks in the recordings, the first positive wave (P1) and the first negative wave (N1). They showed that when participants were actively attending to a display and the P1 and N1 waves arrived about 70ms after the stimulus and 130ms after the stimulus accordingly, and they were both larger than when the stimulus was not actively attended to. ERP's are larger and stronger when we are not attending to them

Answer 41

A steady rhythmic state that lasts for 24 hours. During this 24 hours our body temperature, certain hormonal secretions and other bodily functions undergo a steady rhythmic change that affects out alertness and readies our passage back and forth between waking and consciousness and sleep. These daily biological cycles are called circadian rhythms.

Answer 42

By the brain's suprachiasmatic nuclei (SCN), located in the hypothalamus. These SCN neurons have a genetically programmed cycle of activity and inactivity, functioning like a biological clock. They link the tiny pineal gland, which secretes melatonin, a hormone that has a relaxing effect on the body. The SCN neurons become active during the daytime and reduce the pineal gland's secretion of melatonin, raising the body temperature and heightening alertness. At night SCN neurons are inactive, allowing melatonin levels to increase and promoting relaxation and sleepiness.

Answer 43

Your eyes have neural connections to the SCN, and after a night's sleep, the light of day increases SCN activity and helps reset your 24-hour biological clock. Without this, research shows, people drift into a natural sleep-wake cycle, called a free-running circadian rhythm, which is longer than 24 hours. Under more controlled conditions, the free-running rhythm averages around 24.2 hours. Yet even this small deviation from the 24 hour day is significant. If you were to follow your free-running rhythm, two months from now you would be going to bed at noon and waking at midnight

Answer 44

Compared to night people, morning people go to bed and rise earlier, and their body temperature, blood pressure and alertness peak earlier in the day.

Answer 45

One study found that students from Columbia, Spain and India - regions with warmer annual climates - exhibited greater morningness than students from England, the USA and the Netherlands. In addition to this, a person may inherit the tendency and may be influenced by their physiology to be a morning or evening person. As with many things, both nature and nurture are likely to play a role in this aspect of a person's behaviour.

Answer 46

Jet lag is a sudden circadian disruption caused by flying across several time zones in one day. Flying east, you lose hours from your day; flying west extends your day to more than 24 hours. Jet lag, which often causes insomnia and decreased alertness, is a significant concern for people who frequently travel. the body naturally adjusts about one hour or less per day to time zone changes. Typically, people adjust faster flying west, presumably because lengthening the travel day is more compatible with our natural free-running circadian cycle. Night-shift work is the most problematic circadian disruption for society. Cause disruptions to normal cycles, then on days off or when reverting back to day shits is disrupts the then-alters circadian adjustments made and so your biological clock will have to be adjusted once again.

Answer 47

Combined with fatigue from poor daytime sleep, circadian disruptions can be a recipe for disaster. Job performance errors, fatal traffic accidents, and engineering and industrial disasters peak between midnight and 6am. in some cases, night operators at nuclear power plants have been found asleep at the controls. On-the-job sleepiness is also a major concern among long-distance truck-drivers, airline crews, doctors and nurses

Answer 48

Is a cyclic tendency to become psychologically depressed during certain seasons of the year. Some people become depressed in spring and summer, however, in the vast majority of cases, SAD begins in autumn or winter, when there is less daylight, and then lifts in spring

Answer 49

They may be particularly sensitive to light, so as sunrises occur later in winter, the daily onset of time of their circadian clocks may be delayed to an unusual degree, altering the beginning time of the person's 'biological' morning. On late-autumn and winter mornings, when many people must rise for work and school darkness, SAD sufferers remain in sleepiness mode long after the morning alarm clock sounds

Answer 50

It has been suggested that the seasonal affective disorder increases in the USA, with latitude . The higher the latitude, thee fewer hours of daylight. This relationship was not seen in Europe, although there is some disagreement in the literature. It seems that climate, genetics and sociocultural context all influence SAD

Answer 51

By decreasing alertness, but they do not directly regulate sleep. instead, roughly every 90 minutes while asleep, we cycle through different stages in which brain activity and other physiological responses change in a generally predictable way

Answer 52

In specially equipped laboratories where sleepers' physiological responses are recorded. Electroencephalogram recordings of your brain's electrical activity would show a pattern of beta waves when you are awake and alert. Beta waves have a high frequency (of about 15 to 30 cycles per second, or cps) but a low amplitude, or height. As you close your eyes, feeling relaxed and drowsy, your brainwaves slow down and alpha waves occur at about 8 to 12 cps

Answer 53

When you are alert and awake

Answer 54

Feeling relaxed and drowsy, your brainwaves slow down

Answer 55

As sleep beings, your brainwave pattern becomes more irregular, and slower theta waves (3.5 to 7.5 cps) increase. A form of light sleep from which you can easily be awakened. You will probably spend just a few minutes in stage 1, during which time some people experience dreams, vivid images and sudden body jerks

Answer 56

As sleep becomes deeper, sleep spindles - periodic 1 to 2 second bursts of rapid brainwave activity (12 to 15 cps) - begin to appear. Sleep spindles indicate that you are now in stage 2. Your muscles are more relaxed, breathing and heart rate are slower, dreams may occur, and you are harder to awaken

Answer 57

Sleep deepens as you move into stage 3, marked by the regular appearance of very slow (0.5 to 2 cps) and large delta waves. As time passes, they occur more often, and when delta waves dominate the EEG pattern, you have reached stage 4.

Answer 58

Stage 3 and 4 together are often referred to as slow-wave sleep. Your body is relaxed, activity in various parts of your brain has decreased, you are hard to awaken, and you may have dreams. After 20 to 30 minutes of stage 4 sleep, your EEG pattern changes as you go back through stages 3 and 2, spending little time in each.

Answer 59

Cycle of stages: 1-2-3-4-3-2. At this point, a remarkably different sleep stage ensues. in the AASM classification stages 3 and 4 are described together as a single state (N3) with N3 starting when the brain is expressing 20% Delta waves.

Answer 60

Very slow (0.5 to 2 cps) and large

Answer 61

Stage 3 and 4 sleep together

Answer 62

Rapid eye movements (REM), high arousal and frequent dreaming

Answer 63

Characterised by rapid eye movements (REM), high arousal and frequent dreaming. They found that every half minute or so during REM sleep, bursts of muscular activity caused sleepers' eyeballs to vigorously move back and forth beneath their closed eyelids. Moreover, sleepers awakened from REM periods almost always reported a dream - including people who swore they 'never had dreams'. At last, scientists could examine dreaming more closely by waiting for REM, awaken the sleeper and catch a dream

Answer 64

During REM sleep,physiological arousal may increase to daytime levels. The heart rate quickens, breathing becomes more rapid and irregular, and brainwave activity resembles that of active wakefulness. Regardless of dream content (most dreams are not sexual); men have penile erections and women experience vaginal lubrication. The brain also send signals making is more difficult for voluntary muscles to contract. As as a result, muscles in the arms, legs and torso lose tone and become relaxed. These muscles may twitch, but in effect you are paralysed, unable to move. This state is called REM sleep paralysis, and because of it REM sleep is sometimes called paradoxical sleep: your body is highly aroused, yet it looks like you are asleep peacefully because there is so little movement.

Answer 65

Although each cycle through the sleep stages takes an average of 90 minutes, research shows that as the hours pass, stage 3 drops and REM periods become longer.

Answer 66

It does not have a single 'sleep centre'. Various brain mechanisms control different aspects of sleep, such as falling asleep and REM sleep. Moreover, falling asleep is not just a matter of turning off brain systems that keep us awake. There are separate systems that turn and actively promote sleep

Answer 67

Certain areas at the base of the fore-brain (called the basal fore-brain) and within the brain stem regulate our falling asleep.

Answer 68

Other brain stem areas - including where the reticular formation passes through the pons (called the pontine reticular formation) - play a key role in regulating REM sleep. This region contains neurons that periodically activate other brain systems, each of which controls a different aspect of REM sleep, such as eye movement and muscular paralysis Brain images taken during REM sleep reveal intense activity in limbic system structures such as the amygdala that regulate emotions - a pattern that may reflect the emotional nature of many REM sleep dreams. The primary motor cortex is active, but it signals for movement are blocked and do not reach our limbs. Association areas near the primary visual cortex are active, which may reflect the processing o visual dream images. In contrast, decreased activity occurs in regions of the prefrontal cortex involved in high-level mental functions, such as planning and logical analysis. This may indicate that our sleeping mind does not monitor and organise its mental activity as carefully as when awake, enabling dreams to be illogical and bizarre

Answer 69

In autumn and winter, most people sleep about 15 to 60 minutes longer per night. Shift work, stress at work and school, and night-time noise can decrease sleep quality. Routine can significantly influence our sleeping too - doing the same things at the same time has been shown to be beneficial

Answer 70

Several aspects of sleep, such as its timing and length, vary across cultures. One study of 818 Japanese and Slovak adolescents found that, on average, the Japanese teenagers went to sleep later at night and slept for a shorter time than their Slovak peers. Many people, particularly those living in cultures in tropical climates, enjoy the traditional ritual of one-to-two hour midday nap and reduce the length of night-time sleep. Cultural norms also influence several behaviours related to sleep. In some cultures, people sleep on floors or suspended in hammocks. Co-sleeping, in which children sleep with their parents in the same bed or room, is not common in Europe, as children's sleeping alone is seen as a way o foster independence. but in many cultures, co-sleeping is the norm.

Answer 71

1) We sleep less: 19 to 30 year-olds average around 7 to 8 hours of sleep a night, and elderly adults average just less than 6 hours 2) REM sleep decreases dramatically during infancy and early childhood but remains relatively stable thereafter 3) the time spent in stages 3 and 4 declines. By old age we get relatively little slow-wave sleep

Answer 72

They occur at every age. Sleep surveys indicate that about two-thirds of young adults sleep between 6.5 and 8.5 hours a night. About 1% sleep more than 10 hours a night and 1% less than 5 hours. Similarly, our sleep habits change with age, some teenagers, for instance, falling asleep later, and waking later if allowed to remain in their beds

Answer 73

It appears that the old adage 'everyone needs 8 hours of sleep a night' is not true. Indeed, laboratory studies reveal that a few people function well on very little sleep. Researchers in London examined a healthy, energetic 70 year-old woman who claimed to sleep less than one hour a night. Over 5 consecutive nights at the sleep laboratory, she averaged 67 minutes of sleep a night and showed no ill effects. Such extreme short-sleepers, however, are rare.

Answer 74

Part of the answer appears to reside in our genes. Surveys of thousands of twins in Finland and Australia reveal that identical twins have more similar sleep lengths, bedtimes and sleep patterns than do fraternal twins. Using selective breeding, researchers have developed some genetic strains of mice that are long versus short sleepers, other strains that spend more or less time in REM and still others that spend more or less time in slow-wave sleep The twin studies indicate that differences in sleep length and sleep patterns are also affected by non-genetic factors. Working day versus night jobs, having low-key versus high-pressure lifestyles, and sleeping in quiet versus noisy environments are among the many factors contributing to the variability in people's sleep

Answer 75

A meta-analysis of 19 studies in which participants either underwent 'short-term total sleep deprivation' (up to 45 hours without sleep), 'long-term total sleep deprivation' (more than 45 hours without sleep), or 'partial deprivation' (being allowed to sleep no more than 5 hours a night for one or more consecutive nights). The researchers measured participants' mood (e.g. irritability) and responses on mental tasks (e.g. logical reasoning, word memory) and physical tasks (e.g. manual dexterity, treadmill walking).

Answer 76

All 3 types of sleep deprivation impaired functioning. Combined across all studies, the typical sleep-deprived person functioned only as well as someone in the bottom 9% of non-deprived participants. Overall, mood suffered most, followed by cognitive and then physical performance, although sleep loss significantly impaired all three behaviours

Answer 77

It has been found that university students deprived of one night's sleep performed more poorly on a critical-thinking tasks than students allowed to sleep - yet they incorrectly perceived that they had performed better. It was concluded that students underestimate the negative effects of sleep loss on performance.

Answer 78

In general, it takes several nights to recover and we do not make up all the sleep time that we have lost. It is said that those deprived of sleep and those that are rested function similarly at baseline level. However, sleep-deprived people have the occasional lapses of attention where their functioning suffers. This has become known as the 'lapse hypothesis'. However, research by Dinges et al. (1997) has suggested that the more hours of sleep that are lost the more variable people's reactions become on a typical task that measured the participants' ability to watch out for a target on a screen and respond to it quickly. This variation would not be predicted by the lapse hypothesis

Answer 79

There is some evidence that sleep deprivation can alter people's confidence of how well they have performed a task that requires them to think critically and be vigilant. the effects of sleep loss can depend on the type of task being performed, for example, whether it is complex or simple, whether the person is familiar with it, or whether it is novel, and whether the person is motivated or not. E.g. a complex, novel task with little or no motivation will not be performed well under conditions of sleep deprivation. Research indicates that speed of processing information reduces with the amount of time spent awake, Attention also suffers similarly. More research indicates that memory, and in particular working memory, tasks are harder as we begin to lose sleep

Answer 80

A condition related to sleep deprivation. It is a rare condition that runs in families. Those who suffer with it have relatively normal sleep patterns until they reach middle age where they begin to suffer with chronic and persistent insomnia. After a few years the person dies. The causes are unknown, and the rarity of the condition makes its investigation very difficult

Answer 81

Sleep recharges our run-down bodies and allows us to recover from physical and mental fatigue . Sleep-deprivation research strongly supports this view, indicating that we need sleep to function at out best. If the restoration model is correct,activities that increase daily wear on the body should increase sleep

Answer 82

We don't have any precise answers, but many researchers believe that a cellular waste product called adenosine plays a role. Like a car's exhaust emissions, adenosine is produced as cells consume fuel. As adenosine accumulates, it inhibits brain circuits responsible for keeping us awake, thereby signalling the body to slow down because too much cellular fuel has been burned. During sleep, however, our adenosine levels decrease

Answer 83

That sleep's main purpose is to increase a species' chances of survival in relation to its environmental demands Our prehistoric ancestors has little to gain - and much to lose - by being active at night. Hunting, food gathering and travelling were accomplished more easily and safely during the daylight. Leaving the protection of one's shelter at night would have served little purpose other than to become dinner for night-time predators

Answer 84

Over the course of evolution in terms of its status as predator or prey, food requirements and its methods of defence from attack. For small prey animals such as mice and squirrels, which reside in burrows or trees safely away from predators, spending a lot of time asleep is adaptive. For large prey animals such as horse, deer and zebra, which sleep in relatively exposed environments and whose safety from predator depends on running away, spending a lot off time asleep would be hazardous. Sleep may also have evolved as a mechanism for conserving energy. Our body's overall metabolic rate during sleep is about 10 to 25% slower than during waking rest.

Answer 85

The restoration and evolutionary theories highlight complementary functions of sleep, and both contribute to a two-factor model of why we sleep

Answer 86

Their sleep patterns following the period of disruption are altered, Researchers indicate that even though it may seem counterintuitive, the consequences of REM disruptions are not terribly significant. Patients who have suffered brain injury that results in reduced periods of REM or no REM at all have gone on to perform extremely well both academically and professionally

Answer 87

To answer this, imagine volunteering for a sleep-deprivation study in which we will awaken you only when you enter REM sleep; you will be undisturbed through the other sleep stages. How will your body respond? First, on successive nights, we will have to wake you more often, because your brain will fight back to get to REM sleep. Second, when the study ends, for the first few nights you probably will experience a REM-rebound effect, a tendency to increase the amount of REM sleep after being deprived of it

Answer 88

It is widely considered that high level of brain activity in REM sleep helps us remember important events by enhancing memory consolidation, a gradual process by which the brain transfers information into long-term memory. Researchers have concluded that, while sleep itself foes indeed help us consolidate memory, the amount of REM sleep experienced during sleep makes no difference whatsoever on consolidation. previous research had suggested that relative to neutral types of memory, emotional memory was enhanced during sleep. However, nothing was found to support these theories, but did show that sleep itself was very useful in memory consolidation. Some researchers argue that the function of REM sleep is biological. the periodic high activation of REM sleep keeps the brain healthy during sleep and offsets the periods of low brain arousal during restful slow-wave sleep

Answer 89

A gradual process by which the brain transfers information into long-term memory.

Answer 90

Chronic difficulty in falling asleep, staying asleep or experiencing restful sleep

Answer 91

There is evidence to suggest that insomnia and poor sleep may results in psychological problems. Whereas it is the case that many people with mental health problems do indeed suffer with interrupted or poor sleep patterns, a sleep researcher (Jim Horne), speaking in the telegraph 2009, indicates that there may well be a correlation, and the poor sleep may be caused by the mental illness itself, since good sleep invariably requires an untroubled and clear mind. it is certainly the case that people who sleep poorly may experiences mood changes during the day and have problems concentrating

Answer 92

To some, 20 minutes of lying awake trying to sleep may seem like an hour. Still, insomnia is the most common sleep disorder, experienced by 10-40% of the population of various countries. Some people, however, display paradoxical insomnia; they complain of insomnia but sleep normally when examined in the laboratory.

Answer 93

People can be genetically predisposed. Moreover, medical conditions, mental disorders such as anxiety and depression, and many drugs can disrupt sleep, as can general worrying, stress at home and work, poor lifestyle habits, and circadian disruptions such as jet lag and night-shift work.

Answer 94

One treatment, called stimulus control, involves conditioning your body to associate stimuli i your sleep environment (such as your bed) with sleep, rather than waking activities and sleeplessness. For example, if you are having sleep difficulties, do not study, watch television or snack in your bedroom. Use your bed only for sleeping. If you cannot fall asleep withing 10 minutes, get up and leave the bedroom. Do something relaxing until you feel sleepy, and then return to bed. Other methods for helping insomnia include the application of relaxation techniques, and the careful control of your sleep habits (known as sleep hygiene). Poor sleep hygiene can result in poor sleep, and includes the habit of taking naps during the day, and drinking alcohol or caffeine before bed. In some cases, sleep restriction therapy has been found to be successful. Essentially this means staying awake even if you feel sleepy. This can help the person suffering from insomnia reduce the amount of time they spend awake in their bed trying to fall asleep. By restricting sleep, the insomniac can become tired and fall asleep naturally at the correct time

Answer 95

Alcohol seems to be a bigger problem for women than men when it comes to sleep. Research indicates that whereas alcohol disrupts sleep in both men and women, the effects on men are less pronounced. Alcohol has the effect of deepening sleep at the start of the night but disrupting it later on in the night, but family history and gender moderate the effect. The differences between men and women are to be expected as women and men metabolise alcohol differently. It has been shown that, after drinking, women reported greater feelings of sleepiness than men, slept for less time and that time was more broken than in men. In the study, breath alcohol content was measured throughout the night and showed no differences between male and female participants. They also showed that women tended to show a faster decline in breath alcohol content than men - a reflection of the differences in the way alcohol is metabolised. Since there were very few physiological differences, and since experience and drinking history were controlled, the differences - maybe due to the way alcohol is metabolised - should be considered when investigating the effect alcohol has on sleep

Answer 96

Extreme daytime sleepiness and sudden, uncontrollable sleep attacks that may last from less than a minute to an hour. No matter how much they rest at night, individuals with narcolepsy may experience sleep attacks at any time, with hypnagogic (dream-like) hallucinations and sleep paralysis being common among sufferers

Answer 97

They may go right into a REM stage. People with narcolepsy also may experience attacks of cataplexy, a sudden loss of muscle tone often triggered by excitement and other string emotions. In severe cases, the knees buckle and the person collapses, conscious but unable to move for a few seconds to a few minutes.

Answer 98

An abnormal version of the normal muscular paralysis that takes place during the night-time REM sleep, and some expert's view narcolepsy as a disorder in which REM sleep intrudes into waking consciousness

Answer 99

It can be devastating. People with narcolepsy are more prone to accidents, feel that their quality of life is impaired and may be misdiagnosed by doctors as having a mental disorder rather than a sleep disorder.

Answer 100

Some people may be genetically predisposed towards developing narcolepsy. It can be selectively bred in dogs. In humans, if one identical twin has narcolepsy, the other has a 30% chance of developing it

Answer 101

As an autoimmune disorder - as it has been linked to some specific human antigen variants. An areas in the hypothalamus which produces a neurotransmitter called 'hypocretine' seems to be specifically affected. Thus, patients suffering from narcolepsy typically have very low levels of hypocretine in their cerebrospinal fluid

Answer 102

At present, there is no cure for narcolepsy, but stimulant drugs and daytime naps often reduce daytime sleepiness, and antidepressant drugs (whcih suppress REM sleep) can decrease attacks of cataplexy. The H1N1 virus, better known as Swine Flue, caused great concern, particularly in Europe where many were vaccinated against it. Unfortunately, a relatively small number of children and young adults who had been vaccinated developed narcolepsy as did a number of sufferers of the virus in china. The link between the virus and narcolepsy suggests that there may well have been a predisposition to the sleep disorder that was triggered by the vaccination

Answer 103

The loss of muscle tone that causes normal REM-sleep paralysis is absent. If awakened, RBD patients often report dream content that matches their behaviour, as if they were acting out their dreams

Answer 104

May kick violently, throw punches or get out of bed and move about wildly, leaving the bedroom in shambles, Many RBD patients have injured themselves or their sleeping partners. Research suggests that brain abnormalities may interfere with signals from the brain stem that normally inhibit movement during REM sleep, but in many cases the causes of RBD are unknown. REM-sleep behaviour disorder has aslo been associated with other degenerative diseases such as Parkinson's disease, One possible treatment is to give melatonin as researchers have shown that it is often, but not always, effecting even a year after treatment is over

Answer 105

Unilike RBD, sleepwalking or somnambulism, typically occurs during stage-3 or stage-4 (AASM, N3) period of slow-wave sleep.

Answer 106

Sleepwalkers often stare blankly and are unresponsive to other people. Many seem vaguely conscious of the environment as they navigate around furniture, yet they can injure themselves accidentally, such as by falling down the stairs. Some go to the bathroom or find something to eat. The pattern, however, is variable. People who sleepwalk often return to bed and wake up in the morning with no memory of the event. About 10-30% of children sleepwalk at least once, but less than 5% of adults do. If you did not sleepwalk as a child, the odds are less than 1% you will do so as an adult

Answer 107

It may be inherited, and daytime stress, alcohol, and certain illnesses and medications can increase sleepwalking, with the most likely thing to bring on a bout of sleepwalking i those who suffer from it being a period of sleep deprivation

Answer 108

May include psychotherapy, hypnosis and waking children before the time they typically sleepwalk. But for children, the most common approach is simply to wait for the child to outgrow it while creating a safe sleep environment to prevent injury. Contrary to common belief, waking people who sleepwalk is generally not harmful, the most common experience is that they may be confused for a few minutes and the disorientation may cause them to fall or harm themselves, so it should be done very carefully

Answer 109

Bad dreams, and virtually everyone has them. Like all dreams, they occur more often in REM sleep. Arousal during nightmares typically is similar to levels experienced during pleasant dreams

Answer 110

Frightening dreams that arouse the sleeper to a near-panic state

Answer 111

During slow-wave sleep (stages 3 & 4), are more intense and involve greatly elevated physiological arousal; the heart rate may double or triple. In some cases the terrified sleeper, may suddenly sit up, let out a scream or flee the room - as if trying to escape from something. Come morning, the sleeper usually has no memory of the episode. If brought to full consciousness during an episode - which is hard to do - the person may report a sense of having been choked, crushed or attacked

Answer 112

Up to 6% of children, but only 1-2% of adults experience night terrors. In most childhood cases, the treatment is to simply wait for the night terrors to diminish with age

Answer 113

A period of 10 seconds or more when a person stops breathing

Answer 114

When people repeatedly stop and restart breathing during sleep. Stoppages usually last 20 - 40 seconds but can continue for 1 to 2 minutes. In severe cases they occur 400 to 500 times a night

Answer 115

Most commonly caused by an obstruction in the upper airways, such as sagging tissue as muscles lose tone during sleep. The chest and abdomen keep moving, but no air gets through to the lungs in obstructive apnoea. Finally, reflexes kick in and the person gasps or produces a loud, startling snore, followed by a several second awakening. The person typically falls asleep again without remembering having been awake. In central apnoea the chest and abdomen do not continue to move

Answer 116

About 1-5% of people have some form of sleep apnoea, and the obstructive type is most common among overweight, middle-ages males. Surgery may be performed to remove the obstruction, and sleep apnoea is sometimes treated by having the sleeper wear a mask that continuously pumps air to keep the air passages open, a CPAP - continuous positive airway pressure device. It is often the partner of a person with sleep apnoea - repeatedly woken by the gasps, loud snores and jerking body movements - who encourages the person to seek treatment

Answer 117

Mental activity occurs throughout the sleep cycle. Some student say they experience vivid images soon after going to bed and this is not unusual. When researchers woke college students merely 45 seconds after sleep onset, about 25% of the students reported that they has been experiencing visual hallucinations. As this hypnagogic state - the transitional state from wakefulness through early stage--2 sleep - continued, mental activity became less 'thoughtlike' and more 'dreamlike'. By 5 minutes after sleep onset, visual hallucinations were reported after 40% of awakenings

Answer 118

During REM sleep, hen activity in many brain areas is highest. Awaken a REM sleeper and you have about an 80-85% chance of catching a dream. Stoerig (2017) woke sleepers during REM and 80% reported dreaming at that time. In contrast, people awakened from non-REM (NREM) sleep report dreams abut 15-50% of the time. Also, our REM dreams are more likely to be vivid, bizarre and story-like than NREM dreams. Some researchers attribute this to the fact that REM dreams are typically longer, allowing more time for vivid content to unfold. But like the proverbial chicken and the egg other researchers argue that it is the greater richness of REM dreams that causes them to be longer

Answer 119

No. Even during NREM sleep, hallucinatory images were more common than non-dreamlike thoughts. By some estimates, about 25% of the vivid dreams we have each night actually occur during NREM periods

Answer 120

Analysing 1,000 dream reports (mostly from college students), they found that although some dreams certainly are bizarre, dreams overall are not nearly as strange as they are stereotyped to be. Most take place in familiar settings and often involve people we know

Answer 121

Given the stereotype of 'blissful dreaming', it may surprise you that most dreams contains negative content. In some research, it was found that 80% of dream reports involved negative emotions, almost half contained aggressive acts and a third involved some type of misfortune. They also found that women dreamt almost equally about male and female characters, whereas about two-thirds of men's dream characters were male. Although the reason for this gender difference is not clear, a similar pattern has been found across several cultures and among teenagers and pre-adolescents

Answer 122

E.g. Pregnant women have dreams with may pregnancy themes, and Palestinian children living in violent regions of the Gaza Strip dram about persecution ad aggression more often than do their peers living in non-violent areas. In the weeks following the 9/11 attacks, a study of 1,000 residents of Manhattan found that one in 10 experienced distressing dreams about the attacks. Overall, it appears that up to half of our dreams contain some content reflecting our recent experiences

Answer 123

It is during REM sleep that the majority of dreaming occurs, and we have already described the role REM in memory consolidation. According to evolutionary theory, for instance, the function of dreams might be to prepare us for a hostile environment. Revonsuo (2000) indicates that most dreams have a negative emotional content. It could be that this allows us to experience a dangerous environment in the safety of our dreams

Answer 124

Wish fulfilment - the gratification of our unconscious desires and needs. These desires include sexual and aggressive urges that are too unacceptable to be consciously acknowledged and fulfilled in real life. Freud distinguished between (1) a dream's manifest content - the surface story that the dreamer reports, and (2) its latent content, which is its disguised psychological meaning.

Answer 125

Freud's term for the process by which a dream's latent content is transformed into the manifest content. It occurs through symbols and by creating individual dream characters who combine features of several people in real life. This way, unconscious needs can be fulfilled and, because they are disguised within the dream, the sleeper does not become anxious and can sleep peacefully

Answer 126

They find little evidence that dreams have disguised meaning or that their general purpose is to satisfy forbidden, unconscious needs and conflicts. Critics of dream analysis say that it is highly subjective; the same dream can be interpreted differently to fit the particular analyst's point off view

Answer 127

That beyond the types of unconscious processing discussed, emotional and motivational processes also operate unconsciously and influence behaviour. At times, these hidden processes can cause us to feel and act in ways that mystify us. Consider the case where an amnesia patient could not remember a specific painful experience, but it still influenced her behaviour from the unconscious. Numerous experiments support the view that unconscious processes can have an emotional and motivational flavour

Answer 128

Dreams do not serve any particular function - they are merely a by-product of REM neural activity

Answer 129

When we are awake, neural circuits in our brain are activated by sensory input - sights, sounds, tastes and so on. The cerebral cortex interprets these patterns of neural activation, producing meaningful perceptions. During REM sleep the brain stem bombards our higher brain centres with random neural activity (the activation component). Because we are asleep, this neural activity does not match any external sensory events, but our cerebral cortex continues to perform its job of interpretation. It does this by creating a dream - a perception - that provides the best fit to the particular pattern of neural activity that exists at any moment (the synthesis component)

Answer 130

The brain is trying to make sense of random neural activity. Our memories, experiences, desires and needs can influence the stories that our brain develops, and therefore dream content may reflect themes pertaining to our lives. In this sense, dreams can have meaning, but they serve no special function

Answer 131

It overestimates the bizarreness of dreams and pays too little attention to NREM dreaming. Nevertheless, this theory revolutionised dream research by calling attention to a physiological basis for dreaming, and it remains a dominant dream theory

Answer 132

Because dreams are not constrained by reality, they can help us find creative solutions to our problems and ongoing concerns

Answer 133

Because so many of our dreams do not focus on personal problems, it is difficult to see how problem-solving can be the broad underlying reason for why we dream. They also note that just because a problem shows up in a dream does not mean that the dream involved an attempt to solve it. Moreover, we may think consciously about our dreams after waking and obtain important new insights; in this sense dreams may indeed help us work through ongoing concerns. However, this is not the same as solving problems while dreaming.

Answer 134

Focus on the process of how we dream and propose that dreaming and waking thought are produced by the same mental systems in the brain

Answer 135

Research indicates that there is more similarity between dreaming and waking mental processes than was traditionally believed. Consider that one reason many dreams appear bizarre is because their content shifts rapidly. Yet if you reflect on the contents of your waking thoughts - your stream of consciousness - you will realise that they also shift suddenly. About half of REM dream reports involve rapid content shifts, but when people are awake and laced in the same environmental conditions as sleepers (a dark, quiet room), about 90% of their reports involve rapid content shifts. Thus rapid shifting of attention is a process common to dreaming and waking mental activity

Answer 136

Although there is no agreed-on model of why or even how we dream, theorists are developing models that integrate several perspectives. In general, these models propose that dreaming involves an integration of perceptual, emotional, motivational and cognitive processes performed by various brain modules. For example, the neurocognitive models (such as the activation synthesis model) bridge the cognitive and biological perspectives by attempting to explain how various subjective aspects of dreaming correspond to the physiological changes that occur during sleep. And, as noted previously, these models allow for the possibility that motivational factors - our needs and desires - can influence how the brain goes about its business of attaching meaning to the neural activity that underlies our dreams

Answer 137

A significant part of waking consciousness, providing stimulation during periods of boredom and letting us experience a range of emotions.

Answer 138

Individuals often live in a vivid, rich fantasy world that they control, and most are female

Answer 139

Greater visual imagery than other forms of waking mental activity but tend to be less vivid, emotional and bizarre than night-time dreams. There is also surprising similarity in the themes of daydreams and night-time dreams, suggesting once again that nocturnal dreams may be an extension of daytime mental activity

Answer 140

Like any cell, a neuron us essentially a fragile bag of chemicals, and it takes a delicate chemical balancing act for neurons to function properly. Drugs work their way into the bloodstream and are carried throughout the brain by an extensive network of small blood vessels called capillaries. These capillaries contain a blood-brain barrier a special lining of tightly packed cells that lets vital nutrients pass through so neurons can function. The blood-brain barrier screens out many foreign substances, but some, including various drugs, can pass through. Once inside they alter consciousness by facilitating or inhibiting synaptic transmission

Answer 141

A chemical substance which carries information across the synaptic space to other neurons, muscles or glands e.g. dopamine

Answer 142

A specific group of neurotransmitters that have a widespread and generalised influence on synaptic transmission. Its influence on the transmission of information across the synapse is widespread. Endorphins are a good example of these, having a generalised pain relief and pleasure generating action right across the brain and an antagonist action

Answer 143

First, neurotransmitters are synthesized inside the presynaptic (sending) neuron and stored in vesicles. Next, neurotransmitters are released into the synaptic space, where they bind with and stimulate receptor sites on the postsynaptic (receiving) neuron. Finally, neurotransmitter molecules are deactivated by enzymes or by re-uptake

Answer 144

Certain drugs are designed to interfere in some ways with synaptic transmission. Many of the drugs are entirely legal and carefully controlled, some are illegal. Those that take these drugs aim to alter the synaptic flow, and so interfere with chemical information transmission in the brain. Drugs can have several actions, including those of agonist and antagonist

Answer 145

An agonist drug is a drug that increases the activity of a neurotransmitter. They may: - Enhance a neuron's ability to synthesise, store, or release neurotransmitters - Bind with and stimulate postsynaptic receptor sites (or make is easier for neurotransmitters to stimulate these sites) - Make it more difficult for neurotransmitters to be deactivated, such as by inhibiting re-uptake

Answer 146

An agonist action. Opiates such as morphine and codeine are effective pain relievers. Opiates have a molecular structure similar to that of endorphins in the brain . They bind to and activate receptor sites that receive endorphins. To draw an analogy, think of trying to open a lock with a key. Normally an endorphin molecule acts as they key, but owning to its very similar shape, an opiate molecule can fit into the lock and open it. As far as the brain is concerned, an endorphin has opened the 'lock' and so taking an opiate, such as morphine, or heroin, has the same effect

Answer 147

An agonist action. Amphetamines boost arousal and mood by causing neurons to release greater amounts of dopamine and norepinephrine and by inhibiting re-uptake. During re-uptake, neurotransmitters in the synapse are absorbed back into the presynaptic neurons through special channels. Because the channels back into the presynaptic neuron are filled by the amphetamine, this means that the drugs in the synapse (the gap between the presynaptic neuron and the postsynaptic neuron) can only remain where they are or travel to the postsynaptic receptor sites.

Answer 148

An antagonist drug is a drug that inhibits or decreases the actions of a neurotransmitter. An antagonist may: - Reduce a neuron's ability to synthesise, store or release neurotransmitters - Prevent a neurotransmitter from binding with the postsynaptic neuron, such as by fitting into and blocking the receptor sites on the postsynaptic neuron, or degradation in the synapse

Answer 149

Schizophrenia is a severe psychological disorder whose symptoms may include hallucinations and delusions. Dopamine is a hugely important neurotransmitter and these psychotic symptoms are often associated with over activity within the dopamine system. To restore dopamine activity to more normal levels, pharmaceutical companies have developed drugs with a molecular structure similar, but importantly not identical, to dopamine. Like the lock and key analogy: antipsychotic drugs fit into the dopamine receptor sites but not well enough to stimulate them. In effect, they block up the keyhole, which means that the lock cannot be opened by the dopamine in the system. Dopamine released by presynaptic neurons is blocked and cannot get in, and the schizophrenic symptoms usually decrease

Answer 150

When a drug is used repeatedly, the intensity of effects produced by the same dosage level may decrease over time (decreasing responsivity to a drug)

Answer 151

The body's attempt to maintain a state of optimal physiological balance, called homeostasis. If a drug changed bodily functioning in a certain way, by, say, increasing heart rate, the brain tries to restore balance by producing compensatory responses

Answer 152

Reactions opposite to that of the drug

Answer 153

The body's compensatory responses may continue and, no longer balanced out by the drug;'s effects, the person can experience strong reactions opposite to those produced by the drug.

Answer 154

Occurrence of compensatory responses after discontinued drug use

Answer 155

In the absence of alcohol's relaxing and sedating effects, anxiety and hypertension may be experienced by a chronic drinker

Answer 156

'Rebound insomnia'. This happens with a class of drugs called 'hypnotics' that are designed to help a patient sleep. Stopping these drugs abruptly can cause the patient to suffer with insomnia, which was why they were taking the hypnotic in the first place. The result is that the 'rebound insomnia' is seem by the patient as a re-occurrence of their original insomnia. They believe that they still need the drug, and the habit persists, as the patient lapses and begins taking the drug once more. The person is ow showing the symptoms of drug dependency

Answer 157

Depends partly on the familiarity of the drug setting. Classical conditioning can elicit compensatory responses by associating environmental stimuli with repeated drug use. As drug use continues, the physical setting triggers progressively stronger compensatory responses, increasing the user's tolerance. This helps explain why drug addicts often experience increased cravings when they enter a setting associated with drug use. The environmental stimuli trigger compensatory responses that, without drugs to mask their effect, cause the user to feel withdrawal symptoms

Answer 158

A protective function by physiologically countering part of the drug's effects. If a user takes his or her usual high dose in a familiar environment, the body's compensatory responses are at full strength - a combination of compensatory reactions to the drug itself and also to the familiar conditioned environmental stimuli. But in an unfamiliar environment, the conditioned compensatory responses are weaker, and the drug has a stronger physiological net effect than usual

Answer 159

Maladaptive pattern of substance use that causes a person significant distress or substantially impairs that person's life (drug addiction)

Answer 160

- People can become dependent on drugs, such as cocaine, that produce only mild withdrawal. The drug's pleasurable effects - often produced by boosting dopamine activity - play a key role in causing dependence - Many drug users who quit make it through withdrawal eventually start using again, even though they are no longer physiologically dependent - Many factors influence drug dependence, including genetic predispositions, personality traits, religious beliefs, family and peer influences, and cultural norms

Answer 161

They decrease nervous system activity. In moderate doses, they reduce feelings of tension and anxiety, and produce a state of relaxed euphoria. In extremely high doses, depressants can slow down vital life processes to the point of death

Answer 162

Alcohol is the most widely used recreational drug in many cultures. The World Health Authority indicates that the European region has the highest alcohol consumption of all its regions, with consumption levels twice those of the world average. Alcohol is a major cause of death in Europe. In addition to death, continued consumption of alcohol can cause other problems.

Answer 163

Tolerance developed gradually, and can lead to physiological dependence. Alcohol dampens the nervous system by increasing the activity of GABA, the brain's main inhibitory neurotransmitter, and by decreasing the activity of glutamate, a major excitatory neurotransmitter

Answer 164

In part, the weakening of inhibitions occurs because alcohol's neural slowdown depresses the action of inhibitory control centres in the brain. As for the subjective high, alcohol boosts the activity of several neurotransmitters, such as dopamine, that produce feelings of pleasure and euphoria. At higher doses, however, the brain's control centres become increasingly disrupted, thinking and physical coordination become disorganised, and fatigue may occur as blood-alcohol level (BAL) rises. For reference, the BAL deemed legal for driving in Europe ranges between 0.2mg/ml to 0.8mg/ml

Answer 165

Blood alcohol level is a measure of alcohol concentration in the body. Elevated BALs impair reaction time, coordination and decision-making, and increase risky behaviours. The problem is very serious, so much so that the European Union has set itself a target to halve deaths in road traffic.

Answer 166

It is not just due to lowered inhibitions. Alcohol also produces alcohol myopia, short-sighted thinking caused by the inability to pay attention to as much information as when sober. People who drink start to focus only on aspects of the situation (cues) that stand out. In the absence of strong cautionary cues (such as warnings) to inhibit risky behaviour, they do not think about long-term consequences of their actions as carefully as when they are sober

Answer 167

Physicians sometimes prescribe barbiturates (sleeping pills) and tranquillisers (anti-anxiety drugs e.g. valium) as sedatives and relaxants. like alcohol, they depress the nervous system by increasing the activity of the inhibitory neurotransmitter GABA

Answer 168

They are effective as sleeping pills but are highly addictive. As tolerance builds, addicted people may take up to 50 sleeping pills a day.

Answer 169

At high doses, barbiturates trigger initial excitation, followed by slurred speech, loss of coordination, depression and memory impairment. Overdoses, particularly when taken with alcohol, may cause unconsciousness, coma and even death.

Answer 170

Barbiturates and tranquillisers are widely overused, and tolerance and physiological dependence can occur. Users often do not recognise that they have become dependent until they try to stop and experience serious withdrawal symptoms, such as anxiety, insomnia, and possibly, seizures. It must be said though, that more modern hypnotics (drugs that help someone sleep) do not cause people to suffer quite so badly with these side effects. Some doctors prescribe other drugs for insomnia, such as antidepressants and antihistamines, as these have a sedative effect, but avoid the problem of tolerance.

Answer 171

Increase neural firing and arouse the nervous system. They increase blood pressure, respiration, heart rate and overall alertness. While they can elevate mood to the point of euphoria, they also can heighten irritability

Answer 172

Powerful stimulants prescribed to reduce appetite and fatigue, decrease the need for sleep and reduce depression. Unfortunately, they are widely overused to boost energy and mood

Answer 173

Increase dopamine and noradrenaline (aka norepinephrine) activity. Tolerance develops, and users may crave their pleasurable effects.

Answer 174

Eventually, many heavy users start injecting large quantities, producing a sudden surge of energy and rush of intense pleasure. With frequent injections, they may remain awake for a week, their bodily systems racing at breakneck speed. Injecting amphetamines greatly increases blood pressure and can lead to heart failure and cerebral haemorrhage (stroke); repeated high doses may cause brain damage. There is an inevitable crash when heavy users stop taking the drug. They may sleep for one to two days, waking up depressed, exhausted and irritable. This crash occurs because of the neurons' noradrenaline and dopamine suppliers have become depleted. Amphetamines tax the body heavily.

Answer 175

Cocaine is a stimulant, a powder derived from the coca plant, which grows mainly in western South America. Usually inhaled or injected, it produces excitation, a sense of increased muscular strength and euphoria. Cocaine increases the activity of noradrenaline (norepinepherine) and dopamine by blocking their re-uptake

Answer 176

Can produce vomiting, convulsions and paranoid delusions. A depressive crash may occur after a cocaine high. Tolerance develops too many of cocaine's effects, and chronic use has been associated with an increased risk of cognitive impairments and brain damage.

Answer 177

A chemically converted form of cocaine that can be smoked, and its effects are faster and more dangerous. Overdoses can cause sudden death from cardiorespiratory arrest

Answer 178

Artificially synthesised and has a chemical structure that partially resembles both methamphetamine (a stimulant) and mescaline (a hallucinogen).

Answer 179

Produces feelings of pleasure, elation, empathy and warmth. In the brain, it primarily increases serotonin functioning, which boosts one's mood but may cause agitation. After the drug wears off, users often feel sluggish and depressed - a rebound effect partly due to serotonin depletion. They may have to take increasingly stronger doses to overcome tolerance to ecstasy

Answer 180

Opium and drugs derived from it such as morphine, codeine and heroin

Answer 181

They provide pain relief (the most effective agents known for relieving intense pain in medical use) and cause mood changes which may include euphoria. They stimulate receptors normally activated by endorphins, thereby producing pain relief. They also increase dopamine activity, which may be one reason they induce euphoria

Answer 182

Heroin users feel an intense rush within several minutes of an injection, but they often pay a high price for this transient pleasure. High doses may lead to respiratory depression, which can be fatal, an coma, and overdoses can cause death.

Answer 183

Powerful, mind-altering drugs that produce hallucinations. Many are derived from natural sources; mescaline fir example comes from the peyote cactus. Natural hallucinogens have been considered sacred in many tribal cultures because of their ability to produce unearthly states of consciousness and contact with spiritual forces. Other hallucinogens, such as LSD

Answer 184

They distort sensory experience and can blur the boundaries between reality and fantasy. Users speak of having mystical experiences and of feeling exhilarated. They may also experience violent outbursts, paranoia and panic, and have flashbacks after the trip has ended. The mental effects of hallucinogens are always unpredictable, even if they are taken repeatedly

Answer 185

A powerful hallucinogen that causes a flooding of excitation in the nervous system. Tolerance develops rapidly but decreases quickly. It increases the activity of serotonin and dopamine at certain receptor sites, but scientists still do not know precisely how LSD produces its effects

Answer 186

A product of the hemp plant which is the most widely used and controversial illegal drug which has found a prominent role in popular culture over the years

Answer 187

THC (tetrahydrocannabinol), and it binds to the receptors on neurons throughout the brain. The brain has these receptor sites because the brain produces its own THC-like substances called cannabinoids

Answer 188

It may increase GABA activity, which slows down neural activity and produces relaxing effects. THC also increases dopamine activity, which may account for some of its pleasurable subjective effects.

Answer 189

THC has been shown to have some therapeutic potential, for example in cases of chemotherapy-induced nausea, in some pain conditions and as a drug that may alleviate some symptoms of multiple sclerosis.

Answer 190

However, there is research linking the use of cannabis with clinical manifestations of psychological disorders such as schizophrenia and certainly schizotypal personality symptoms

Answer 191

- That chronic use causes people to become unmotivated and apathetic towards everything, a condition called amotivational syndrome. - Another misconception is that marijuana causes people to start using more dangerous drugs. Neither statement is supported by scientific evidence. - A third misconception is that using marijuana has no significant dangers. In fact, marijuana smoke contains more cancer-causing substances than does tobacco smoke. At high doses, users may experience negative changes in mood, sensory distortions, and feelings of panic and anxiety. While users are high, marijuana can impair their reaction time, thinking, memory, learning and driving skills - Another misconception is that users cannot become dependent on marijuana. Actually, repeated marijuana use produces tolerance and, at typical doses, some chronic users may experience mild withdrawal symptoms, such as restlessness. People who use chronically high doses and suddenly stop may experience vomiting, disrupted sleep and irritability. About 5-10% of people who use marijuana develop dependence

Answer 192

Animal research indicates that genetic factors influence sensitivity and tolerance to drugs' effects. The most extensive research has focused on alcohol. Rats and mice and can be genetically bred to inherit a strong preference for drinking alcohol instead of water.. Even in their first exposure to alcohol, these rats show greater tolerance than normal rats. Among humans, identical twins have a higher concordance rate for alcoholism than so fraternal twins. Scientists have also discovered a gene which is found more often among alcoholics and their children than non-alcoholics and their offspring, that is thought to influence how the brain responds to alcohol. People who grow up with alcoholic versus non-alcoholic parents respond differently to drinking alcohol under laboratory conditions. Adults who had alcoholic parents typically display faster hormonal and psychological reactions as blood-alcohol levels rise, but these responses drop off more quickly as blood-alcohol levels decrease. Compared with other people, they must drink more alcohol over the course of a few hours to maintain their feeling of intoxication. Overall, many scientists see evidence for a genetic role in determining responsiveness and addiction to alcohol

Answer 193

At the psychological level, people's beliefs and expectancies can influence drug reactions. Experiments show that people may behave as if drunk if they simply think they have consumed alcohol but actually have not. If a person's fellow drinkers are happy and gregarious, he or she may feel it is expected of them to respond the same way. Personality factors also influence drug reactions and usage. People who have difficulty adjusting to life's demands or whose contact with reality is marginal may be particularly vulnerable to severe and negative drug reactions and to drug addiction

Answer 194

The physical and social setting in which a drug is taken can strongly influence a user's reactions. Being in a familiar drug-use setting can trigger compensatory physiological responses and cravings. Moreover, the behaviour of other people who are sharing the drug experience provides important cues fro how to respond, and a hostile environment may increase the chances of a bad trip with drugs such as LSD. Cultural learning also affects how people respond to a drug. In many western cultures, increased aggressiveness and sexual promiscuity are commonly associated with drunken excess. In contrast, members of the Camba culture of Bolivia customarily drink large quantities of an almost pure alcohol, remaining cordial and non-aggressive between episodes of passing out.

Answer 195

Traditionally, members of the Navajo tribe do not consider drinking any amount of alcohol to be normal, whereas drinking wine or beer is central to social life in some European countries. In some cultures, hallucinogenic drugs are feared and outlawed, whereas in others they are used in medicinal or religious contexts to seek advice from spirits.

Answer 196

A state of heightened suggestibility in which some people are able to experience imagined situations as if they were real

Answer 197

Firstly because of its use in treating mental disorders. Hypnosis is not just a stage act. Many universities offer modules and courses in hypnosis with scientists exploring hypnosis as a unique state of altered consciousness. Those hypnotised act decisively and ably, and so demonstrate primary consciousness, but they do not demonstrate self-awareness. Hypnosis then, may be a different kind of consciousness

Answer 198

The process by which one person leads another person into hypnosis. A hypnotist may ask the subject to sit down and gaze at an object on the wall, and then, in a quiet voice, suggest that the subject's eyes are becoming heavy. The goal is to relax the subject and increase his/her concentration. Induction may be achieved by fixed-gaze where any object can be used as a focal point. It may be achieved by progressive relaxation and imagery where the subject is encouraged, gently, to imagine themselves somewhere relaxing. A third induction route is rapid induction where the hypnotist speaks forcefully, and convincingly. the idea here is that the nervous subject is confused in some way, with their conscious mind overloaded suddenly resulting in a hypnotic state

Answer 199

a standard series of pass-fail suggestions that are read to a subject after a hypnotic induction. the subject's score is based on the number of passes. About 10% of subjects are completely non-responsive, 10% pass all or nearly all items, and the rest fall in between. There is evidence that susceptibility may have a genetic element.

Answer 200

No. You have to be susceptible to hypnotic suggestions

Answer 201

They subjectively experience their actions to be involuntary. To hypnotised subjects, it really feels like their hands are being pushed apart by a mysterious force rather than by their conscious control. However, there is some research to suggest that hypnosis has the power to get people to act against their will (however, this was shown by Milgram who did this not with hypnosis but with an authority figure)

Answer 202

One study hypnotised people who were allergic to leaves and told them it was harmless and to hold it. 4 out of 5 had no allergic reaction. Then people who had no allergies were hypnotised and rubbed with a leaf they were told was toxic and all people had an allergic reaction to the harmless leaf

Answer 203

For patients who experience chronic pain, hypnosis can produce relief that lasts for months or even years. Brain-imagine research reveals that hypnosis modifies neural activity in brain areas that process painful stimuli, but non-hypnotic techniques, such as mental imagery and performing distracting cognitive tasks, also alter neural functioning and reduce pain

Answer 204

We do not know exactly, It may influence the release of endorphins, decrease patients' dear of pain, distract patients from their pain or somehow help them separate the pain from the conscious experience. It may also be that those who have experienced hypnosis may experience an expectation of positive or pain-killing effects which may themselves influence the resulting experience of pain

Answer 205

You may have seen hypnotised people being given a suggestion that they will not remember something (e.g. pet name) either during the session itself (hypnotic amnesia) or after coming out of hypnosis (post-hypnotic amnesia). A reversal cue also is given, such as a phrase (e.g. 'remember') that ends the amnesia once the person hears it. Research indicates that about 25% of hypnotised college students can be led to experience amnesia. Although researchers agree that hypnotic and posthypnotic amnesias occur, they debate the causes. Some feel it results from voluntary attempts to avoid thinking about certain information; others believe it it caused by an altered state of consciousness that weakens normal memory systems

Answer 206

Law enforcement agencies sometimes use hypnosis to aid the memory of eyewitnesses to crimes. Despite occasional success stories, controlled experiments find that hypnosis does not reliably improve memory. In some studies where participants watch simulates bank robbery videos, and when questioned hypnotised or not, the hypnotised people display better recall than non-hypnotised people but then no better recall in others.

Answer 207

They could be pseudomemories, false memories created during hypnosis by statements or leading questions made in by the examiner. In some experiments, hypnotised and non-hypnotised subjects are intentionally exposed to false information about an event. Later, after the hypnotised subjects have been brought out of hypnosis, all participants are questioned. Highly susceptible people who have been hypnotised are more likely to report the false information as being a true memory, and often are confident that their false memories are accurate

Answer 208

Many courts have banned or limited testimony obtained under hypnosis. The increased suggestibility of hypnotised people makes them particularly susceptible to memory distortion caused by leading questions, and they may honestly come to believe facts that never occurred.

Answer 209

The view of hypnosis as an altered state involving a division (dissociation) of consciousness. Hilgard (1977, 1991) proposed that hypnosis creates a division of awareness in which the person simultaneously experiences two streams of consciousness that are cut off from one another. One stream responds to the hypnotist's suggestions, while the second stream - the part of consciousness that monitors behaviour - remains in the background but is aware of everything that goes on. Hilgard refers to this second part of consciousness as the hidden observer. For Hilgard, this dissociation explained why behaviours that occur under hypnosis seem involuntary or automatic. Given the suggestion that 'your arm will start to feel lighter ad begin to rise', the subject intentionally raises their arm, but only the hidden observer is aware of this. The main stream of consciousness that responds to the command us blocked from this awareness and perceives that the arm is rising all by itself

Answer 210

They propose that hypnotic experiences result from expectations of people who are motivated to take on the role of being hypnotised. To these theorists, hypnosis does not represent a special state of dissociated consciousness. Most people believe that hypnosis involves a trance-like state and responsiveness to suggestions. People motivated to conform to this role develop a readiness to respond to the hypnotist's suggestions and to perceives hypnotic experiences

Answer 211

No. Role theorists emphasise that when people immerse themselves in the hypnotic role, their responses are completely real and may indeed represent altered experiences. Our expectations strongly influence how the brain organises sensory information. Often, we literally see what we expect to see. According to social cognitive theory, many effects of hypnosis represent an extension of this principle The hypnotised subject whose arm automatically rises in response to a suggestion genuinely perceives the behaviour to be involuntary because this is what the subject expects and because attention is focused externally on the hypnotist and the hypnotic suggestion

Answer 212

Results converge with other physiological findings in leading to an important conclusion: hypnotised people are not faking it but rather are experiencing an altered state of brain activation that matched their verbal reports. Studies reveal that giving hypnotised subjects pain-reducing suggestions not only decreases their subjective report of pain but also decreases activity in several brain regions that process pain signals However, the extent to which people's expectations bring about this state and whether it is a dissociated state are still unclear

Consciousness (chapter 6) Flashcards

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