Biopsychology Flashcards
(64 cards)
1
Q
What is the human nervous system for?
A
Allow us to gain information about the environment and respond to it.
2
Q
What 2 parts is the human nervous system made up of?
A
Central nervous system:
- Is where all complex processing of information happens and decisions are made.
Peripheral nervous system:
- Brings information from the senses to the CNS and transmits information from CNS to muscles and glands.
3
Q
What is the CNS made up of?
A
Brain:
Centre of awareness and co-ordinates all sensory, intellectual and nervous activity.
Spinal cord:
Relays information from the brain to the rest of the body allowing the brain to monitor bodily functions like breathing and digestion and voluntary movement.
4
Q
What is the peripheral nervous system made up of?
A
Somatic nervous system:
Voluntary, made up of 12 cranial nerves including sensory and motor neurones which relay information to and from the CNS. And involved in some reflexes.
Autonomic nervous system:
Governs the brains involuntary actions like breathing and digestion and is self regulating and is made up of:
Sympathetic nervous system:
Involved in emergency responses like fight or flight, releases noradrenaline to speed bodily processes up and also slows down others like digestion.
Parasympathetic nervous system:
Rest and digest, involved in calming the body and slowing down after emergency responses.
5
Q
What are nerves?
A
Bundles of nerve fibres enclosed in myelin sheath.
6
Q
What is a sensory neurone and draw it.
A
Carries nerve impulses from sensory receptors to the spinal cord and brain.
7
Q
What is a motor neurone and draw it.
A
Conducts signals from the CNS to effectors. Has its cell body in the CNS but has long axons that reach the PNS.
8
Q
What is a relay neurones and draw it.
A
Relay neurones allow sensory and motor neurones to communicate.
9
Q
What is an example of a reflex arc and the 4 steps?
A
The knee jerk reflex.
1. A stimulus such as a hammer hits the knee
2. This is detected by sensory receptors (in the PNS) which generate a nerve impulse which travels along the sensory neurone.
3. Reaches the spinal cord and connects via a relay neurone to the motor neurones.
4. This transfers the message to an effector e.g muscle, which causes leg to contract and knee to jerk.
10
Q
Draw diagram of synaptic transmission.
A
11
Q
What is the 5 steps of synaptic transmission?
A
- Action potential (nerve impulses) travels down the neuron via the axon and arrives at the pre synaptic terminal.
- This action potential stimulates neurotransmitters to be released.
- The neurotransmitters leave the presynaptic terminal and diffuse across the synaptic cleft.
- The neurotransmitters bind to the receptors on the post synaptic terminal and the level of IPSP’s and EPSP’s determine whether the neuron fires or not.
- Any excess neurotransmitters are broken down in the synaptic cleft or reabsorbed into the presynaptic cell.
12
Q
What is the definition of neurotransmitter?
A
They are chemical messengers that carry signals across the synaptic cleft to the post synaptic terminal.
13
Q
What is the definition of summation?
A
The added effects of excitatory and inhibitory neurotransmitters on the post synaptic cell.
14
Q
Describe the process of excitation and inhibition. (6 marks).
A
These neurotransmitters e.g noradrenaline may have an excitatory effect which increases the likelihood of an excitatory signal being sent to the post synaptic neurone which in turn makes the neurone more likely to fire.
The excitatory neurotransmitters bind to the post synaptic receptors which cause a chemical change to the membrane, resulting in excitatory post synaptic potentials, meaning the postsynaptic cell is more likely to fire.
Inhibitory neurotransmitters decrease the likelihood of a neurone firing after they have binded to the postsynaptic receptors.
Inhibitory neurotransmitters usually have a calming effect on behaviour, e.g serotonin is involved in mood regulation.
15
Q
What charge do these have:
Resting potential
Threshold
Action potential firing
Hyperpolarisation
A
- -70
- -55
- +30
- Less than -70
16
Q
Draw diagram of action potential firing.
A
17
Q
What is the definition of the endocrine system?
A
Produces and secretes chemical messengers called hormones.
18
Q
What is the definition of a hormone?
A
Chemical messengers that are secreted by endocrine glands into the bloodstream and are carried to target sites throughout the body. They influence many processes e.g mood, the stress response and bonding between mother and infant. They bind to receptors on target organ cells.
19
Q
What are the 6 main endocrine glands?
A
Hypothalamus, pituitary, adrenal, pineal, testes, ovaries.
20
Q
What does the hypothalamus do? (2)
A
Links the nervous system to the endocrine system and maintains homeostasis.
Controls the pituitary gland as it releases corticotropin releasing hormone which stimulates the pituitary gland.
21
Q
What does the pituitary gland do and what 2 parts is it made up of? (3)
A
It’s known as the ‘master gland’. Its main role is to stimulate the release of hormones from other glands but can also release hormones that have a direct effect.
Anterior pituitary:
Releases adrenocorticotrophic hormone (ACTH) which stimulates the adrenal glands to produce cortisol and also releases LH and FSH which stimulates the ovaries and testes.
Posterior pituitary:
Releases oxytocin which stimulates contractions during birth and mother-daughter bonding.
22
Q
What does the adrenal gland do and its 2 parts? (4)
A
Regulates the biological effects of the fight or flight response.
Adrenal cortex (outer):
Releases cortisol, the stress hormone which influences many bodily functions like cardiovascular and anti-inflammatory. If it is low, blood pressure will drop, poor immune functions and inability to deal with stress will occur.
Adrenal medulla (inner):
Releases adrenaline and noradrenaline which control fight or flight. Adrenaline increases heart rate and blood flow to brain and muscles and noradrenaline constricts the blood vessels to increase blood pressure.
23
Q
What does the pineal gland do?
A
Releases melatonin which is involved in the sleep wake cycle and biological rhythms.
24
Q
What is the journey of a hormone? (3)
A
- Gland stimulation: either by the anterior or posterior pituitary by electrical signal or chemical change.
- Hormone release: released into the bloodstream and carried to target sites.
- Effector binding: Hormone binds to receptors on target organ cells.
25
What are the 6 steps of the fight or flight response (SAM pathway)?
1. Amygdala perceives the situation as dangerous which is appraised by the cerebral cortex.
2. Amygdala sends signal to alert the hypothalamus which activates the SAM (sympathomedullary) pathway.
3. The sympathetic branch of the autonomic nervous system is activated which stimulates part of the adrenal glands called the adrenal medulla.
4. The adrenal medulla produces and releases adrenaline and noradrenaline into the bloodstream.
5. This prepares the body for fight or flight, it increases heart rate, dilates pupils, increases blood flow to brain and muscles, slows digestion and increases respiration.
6. The parasympathetic nervous system, from the ANS, brings the body back down to optimum functioning by ‘rest and digest’.
26
What is the body’s response to chronic (ongoing) stress?
When the body continues to perceive a situation as dangerous, the second system kicks in as the hypothalamus activates the HPA axis.
27
What are the 3 steps of the HPA axis?
1. The hypothalamus releases corticotropin releasing hormone (CRH) into the bloodstream.
2. CRH stimulate the pituitary gland to produce and secret adrenocorticotrophic hormone (ACTH) into the bloodstream which is transported to the adrenal glands.
3. ACTH stimulate part of the adrenal gland called the adrenal cortex (outer) to release cortisol, the stress hormone, which creates a burst of energy and reduces sensitivity to pain.
28
What is the evaluation about ‘freeze’ in fight or flight response?
Gray argues that the first phase of response to threat is not to fight or flee but to freeze and avoid confrontation.
For example, Gray 1988 proposed the idea of fight, flight or freeze. He said that freeze happens first and in stressful situations to gather more information before reacting. AKA stop look and listen.
The adaptive advantages of this response for humans is that freezing focuses our attention and allows us to look for new information in order to make the best response for that particular threat.
29
What is the evaluation about tend and befriend for the fight or flight response?
Taylor et al 2000 suggested that for females, behavioural responses to stress are more characterised by tend and befriend rather than fight or flight.
For example, this involves women protecting themselves and their children through nurturing behaviours (tending) and by forming protective alliances with other women (befriending). Evolutionarily, the women would have been caring for the children as they had the role of the primary caregiver and so fleeing with one or more children would have been extremely difficult. Additionally, fleeing at any sign of danger would have put the offspring at risk. Furthermore, these gentle behaviours in women may cause the assailant to trust that they wont hurt them or call the police, potentially resulting in life saving bargaining.
Therefore, this finding explained in terms of high levels of the hormone oxytocin in women, suggests that previous research focused on males, may have obscured the patterns of stress response in women.
30
What is the evaluation about SRY gene for fight or flight response?
Lee and Harley 2012 have found evidence of a genetic basis for gender differences in the fight or flight response.
For example, the SRY gene is located on the Y chromosome and so is only possible to be present in males. This gene is thought to promote aggression and result in the fight or flight response to stress. The SRY gene may prime males to respond to stress in this way through the realise of adrenaline and through increased blood flow to organs involved in the fight or flight response.
In contrast, the absence of the SRY gene in females may prevent this response to stress, instead leading to more ‘tend and befriend’ behaviours.
31
What is the definition of localisation of function?
Refers to the belief that spe0cific brain regions are associated with specific cognitive processes.
32
What are the 6 key localised brain regions?
Motor cortex, somatosensory cortex, visual cortex, auditory cortex, Broca’s area, Wernicke’s area.
33
What do the motor and somatosensory cortex do?
Motor:
Located in prefrontal cortex next to the pre central gyrus and responsible for all voluntary motor movements.
Sends nerve impulses to muscles
Different parts of the motor cortex control different parts of the body but are arranged logically.
Somatosensory cortex:
Located in parietal lobe and can detect where the sense came from originally.
Processes sensory information related to touch, pressure, pain and temperature of skin.
34
What do the visual cortex and the auditory cortex do and their stages?
Visual cortex:
- Located in occipital lobe but visual processing actually starts in the retina:
1. Nerve pulses from the retina travel along the optic nerve.
2. To the thalamus which is a relay station that passes it on to the visual cortex.
Auditory cortex:
- Located in the upper temporal lobes.
1. Auditory processing starts in the cochlea which converts sound waves into nerve impulses which travel along the auditory nerve to the brain stem
2. Then stop at the thalamus to be sorted and further relayed to the auditory cortex.
35
What are the 3 points about Broca’s area?
1. Located in posterior left frontal lobe.
2. Discovered by Paul Broca investigating a patient he referrred to as ‘tan’ as this was the only syllable he could produce. He could understand spoken language but could not produce speech or express himself in writing.
3. He then looked at 8 other patients all of whom had similar difficulties and also lesions in the left frontal hemisphere. Leading to him identifying the language centre in this area where damage causes Broca’s aphasia.
36
What are the 3 points about Wernicke’s area?
1. Located in the posterior left temporal lobe.
2. Discovered by Carl Wernicke
3. People with damage to this area were able to produce speech but unable to understand language so their speech did not make much sense. This is called fluent aphasia.
37
What is the evaluation about evidence for different functions of Broca’s and Wernicke’s area?
Evidence for the different functions of Broca’s and Wernicke’s area come from the discovery that damage to each different area results in different types of aphasia.
For example, expressive aphasia (Broca’s aphasia) is the impaired ability to produce language. In most cases, this results from brain damage to Broca’s area. Alternatively, receptive aphasia (Wernicke’s aphasia) is an impaired ability to understand language, and extract meaning from spoken or written words. This type of aphasia usually results from damage e.g a stroke to Wernicke’s area.
This demonstrated the important role played by these brain regions in different aspects of language.
38
What is the evaluation about how brain areas communicate being more important than localised function?
Research suggests that what may be more important is how different brain areas communicate rather than which brain regions control a particular cognitive process.
For example, Wernicke claims that although different regions of the brain have different specialised functions, they are still interdependent in the sense that in order to work, they must interact with each other. For example, in 1892 a neurologist called Joseph Dejerine described a case where the loss of ability to read resulted from damage to the connection between the visual cortex and Wernicke’s area.
This suggests that complex behaviours such as language, reading and movement are gradually built up as a stimulus enters the brain, then moves throughout different structures before producing a response. Damage to the connection between any 2 points in this process results in impairments that can resemble damage to the localised brain region related with a specific function.
39
What is the evaluation about Dronkers et al using MRI?
Dronkers et al 2007 re-examined the preserved brain of 2 of Broca’s patients known as ‘tan’ and Lazare Lelong. They used modern high resolution brain MRI imaging to identify the extent of lesions in more detail.
For example, the findings of the MRI revealed that other areas besides Broca’s area may have contributed to patients’ reduced speech abilities. These findings are significant as although lesions to Broca’s area alone can result in temporary speech disruption, they do not usually result in severe disruption to spoken language.
This study suggests that language and cognition are much more complicated than once thought, involving networks of brain regions rather than being localised to specific areas.
40
What is the definition of hemispheric lateralisation?
Means that the 2 halves of the human brain each have their own functional specialisation e.g the left side is dominant in language and the right side excels at visual motor tasks. The 2 hemispheres are connected by a bundle of nerve fibres called the corpus callosum which is why we can talk about things experienced in the right hemisphere.
41
What is the definition of split brain research?
Research that studies individuals who have been subjected to a surgical separation of the 2 hemispheres of the brain due to severance of the corpus callosum.
42
Who is the key study for split brain research?
Sperry and Gazzinga 1967
43
What is Sperry and Gazzinga’s procedure and findings?
1. Natural experiment as the participants had already had their corpus callosum’s severed due to severe epilepsy.
2. 11 participants- 10 men and 1 woman
3. Took part in a range of visual and tactile tasks:
Visual:
Participants had to focus on a point in the middle of a screen and words or images were flashed into their left, right or both visual fields for 1/10th of a second. They then had to point to, draw or describe the object.
Tactile:
Objects were placed in either the left or right hand behind a screen.
FINDINGS:
Words or images flashed into the left visual field could be drawn or pointed to even though they insisted they hadn’t seen anything whereas words or images flashed into the right visual field were able to be written or described in speech.
Objects sensed by the left hand were unable to be retrieved by the right hand but objects placed in the right hand were able to be verbally described.
44
What are the conclusions of Sperry and Gazzinga’s research?
Information from the left visual field is processed in the right hemisphere and vice versa. Because the 2 hemispheres were severed in the particiapants, they could not communicate with each other. The left hemisphere holds the language centres: Broca and Wernicke’s areas so info presented to the right hand or visual field was able to be communicated out loud whereas the right hemisphere couldn’t. Therefore, this research supports lateralisation of brain function.
45
What is the evaluation about split brain procedure being rarely carried out so small samples?
Split brain patients are rare as the procedure is rarely carried out nowadays and Andrewes 2001 points out that many studies are presented with as few as 3 participants or even just 1.
Andrewes claims that, in some cases, conclusions have been drawn from individuals who either have a confounding physical disorder that made the split brain procedure necessary, or participants have had a less complete sectioning of the 2 hemispheres than was originally thought. As a result, patients who have had the split brain procedure without these confounding factors are rarely encountered in sufficient numbers useful for research. Furthermore, it is unethical to replicate Sperry and Gazzinga’s study as healthy participants would have to undergo the split brain procedure.
Therefore, split brain study results have been unable to be replicated in more recent years.
46
What is the evaluation about language not being completely restricted to left hemisphere for split brain research?
Language may not be completely restricted to just the left hemisphere. Gazzinga 1998 suggests that discoveries from early split brain research have been disconfirmed by more recent discoveries.
For example, damage to the left hemisphere was found to be far more detrimental to language function than damage to the right hemisphere. However, case studies have demonstrated that this may not necessarily be the case. One patient known as J.W developed the capacity to speak out of his right hemisphere with the result that he can now talk about information presented to either the left or the right brain (Turk et al 2002).
Therefore, this evidence challenges the claim that the right hemisphere is unable to understand even the most rudimentary language.
47
What is the evaluation about the main strength of hemispheric lateralisation?
A main strength of hemispheric lateralisation appears to be that it increases the neural processing capacity.
For example, by only using one hemisphere to engage in a particular task such as language or maths ability, it would leave the other hemisphere free to engage in another function. However, despite this assumption, very little empirical evidence has been provided to show that lateralisation confers any advantage to the functioning of the human brain. On the other hand, Roger’s et al 2004 found that in domesticated chickens, brain lateralisation was associated with an enhanced ability to multitask.
Therefore, this finding does provide some evidence that brain lateralisation enhances brain efficiency in cognitive tasks requiring simultaneous but different uses of both hemispheres.
48
What is the evaluation about lateralisation not being the same for someone’s whole life?
Lateralisation of function appears not to stay exactly the same throughout an individual’s lifetime, but changes with normal ageing.
Lateralisation patterns found in younger individuals tend to switch to bilateral patterns in healthy older adults. For example, Szaflarski et al 2006 found that language becomes more lateralised to the left hemisphere with increasing age in kids and adolescents but after the age of 25, lateralisation decreases with every decade of life.
It is difficult to know why this is the case but one possibility is that using the extra processing resources of the other hemisphere may in some way compensate for age related declines in function.
49
What is the definition of plasticity?
Refers to the brain’s ability to modify its own structure and functions as a result of experiences. New neural pathways are formed due to learning.
50
What is the definition of functional recovery?
Refers to the recovery of abilities and mental processes that have been compromised by a brain injury or disease. Moving functions from a damaged area to an undamaged area after a traumatic event.
51
What are the 3 points about plasticity?
The more a synaptic connection is fired, the more efficiently it grows.
As we age, synaptic pruning occurs which makes pathways more specialised and efficient.
Pathways that are infrequently used become weak and die.
52
Who are the research evidence?
Kühn et al 2014
Maguire 2000
Kempermann et al 1998
53
What is Kühn’s research?
1. Compared a control group with a video training group who trained for 2 months for 30 mins a day on super Mario.
2. He found a significant increase in grey matter of various areas including the cortex, the hippocampus and the cerebellum in the videogame group and no increase in the control.
4. Kühn concluded that videogame training results in new synaptic connections.
54
What is Maguire’s research?
1. A study of London taxi drivers discovered that changes in the brain could be detected as a result of extensive experiences of spatial navigation.
2. Maguire used MRI scanning to calculate the volume of grey matter in taxi drivers and of a control group.
3. He found that the posterior hippocampi of the taxi drivers was significantly larger than the control group. Additionally, a positive correlation was found between hippocampal volume and length of time spent as a taxi driver.
4. This not only shows that larger hippocampal volume was found in those with job related experience of spatial navigation but also that greater plasticity was found in those who use the connections more often.
55
What is the evaluation about Maguire’s research?
However, some psychologists suggest that research investigated plasticity of the brain is flawed.
For example, Maguire did not test the taxi drivers before they became taxi drivers so a clear change in structures of the brain as a result of experience cannot be concluded. They may have had larger hippocampi before becoming taxi drivers.
Therefore, as a cause and effect relationship between experience and change in the brain cannot be definitively established, further research into the plasticity of the brain is necessary.
56
What is Kempermanns research?
1. Kempermann et al 1998 suggested that an enriched environment could alter the number of neurons in the brain.
2. He found evidence of an increased number of new neurons in the brains of rats in a complex environment compared to those in a lab cage.
3. The rats in a complex environment showed a specific increase in hippocampus, associated with new memory formation and navigation.
4. This shows clear evidence of the brains ability to change as a result of experience.
57
What are the 2 points about functional recovery?
1. Other areas can take over by neuronal unmasking which is where usually the input is not strong enough but due to damage in the area, dormant synapses can be regenerated in nearby areas, allowing new connections to be activated recovering the damaged functions.
2. Stem cells can also be used in the recovery of functions in the brain. These are unspecialised cells which can take on the characteristics of nerve cells in damaged areas of the brain, allowing new neural pathways to be formed and recovering any damage to existing cells preventing effective neurotransmission.
58
What is the research evidence for functional recovery?
Taijiri et al 2013:
1. Found that stem cells provided to rats after a brain injury showed clear development of new nerve-like cells in the area of injury.
2. This demonstrates the brains ability to create new connections using neurons manufactured by stem cells.
59
What is the evaluation for functional recovery?
Whilst there is evidence for functional recovery, it is possible that this ability may deteriorate with age.
For example, Elbert et al found that the capacity for neural reorganisation is much greater in children than it is in adults. This may explain why change is much more demanding for adults than it is for children and also coins the term ‘you cant teach an old dog new tricks’.
Therefore, individual differences must be considered when assessing the likelihood of functional recovery in the brain after a traumatic injury.
60
What are the 4 brain scanning techniques?
Post mortem examination, fMRI, EEG and ERP
61
What is post mortem examination and the strengths and limitations?
Researchers study people that display a particular behaviour whilst they are alive which suggests potential brain injury. For example, Paul Broca examined the brain of a patient who displayed speech problems when alive. He found that there were lesions on the area of the brain involved in speech production which is now known as Broca’s area.
Strengths:
1. Allows a more in depth examination of brain tissue and deeper brain structures can be investigated.
2. Changes in neurotransmitter levels can be measured in the brain which has resulted in important understandings of schizophrenia.
Limitations:
1. Only provides spatial resolution which is identifying the exact location an activity took place.
2. Diverse causes of death may have damaged brain tissues meaning there are many confounding variables in the post mortem study of the brain.
3. It only provides retrospective data as it is too late to test hypotheses about cognitive functions related to specific brain activities.
62
What is fMRI and what are the strengths (3) and limitations (2)?
Functional magnetic resonance imaging measure the changes in blood flow in the brain in order to see which parts have more neural activity whilst performing a particular task.
Strengths:
1. Very good spatial resolution of about 1mm which allows accurate measurements to be made. Precisely identifying areas of brain activation or patterns of activation over time whilst the participant completes experimental conditions.
2. Safe and noninvasive as no insertion of instruments or exposure to harmful radiation so can examine living brains with no harm.
3. More objective than verbal reports of psychological processes so it can be useful in brain phenomena’s can be identified which cannot be verbally described.
Limitations:
1. Not very good temporal resolution as only one picture is taken every few seconds and there is a delay in blood flow after activity so some brain processes are just too fast to be measured.
2. Ignores the networked nature of the brain which is an issue as communication between different brain regions may be more important than localised activity.
63
What are EEG’s and strengths (1) and limitations (2)?
Electroencephalograms measure electrical activity through electrodes attached to the scalp. Small electrical changes are detected by electrodes that are graphed over a period of time and indicate the level of activity in the brain. Amplitude shows intensity of brain wave and frequency shows speed of activation.
Strengths:
1. They have very good temporal accuracy measuring brain resolution in the first few milliseconds allowing researchers to accurately measure particular tasks or activities and the brain activity associated with it.
Limitations:
1. Only detects activity in the superficial regions of the brain meaning that deeper areas like the hypothalamus and hippocampus would not show up.
2. It is not very good at pinpointing the exact source of activity in the brain as neighbouring electrodes pick up electrical activity from overlapping areas.
64
What are ERP’s and what is the strengths?
Event related potentials use the same technique and equipment as EEG’s as they also measure changes in voltage in the brain during a particular task or event. Establishing a specific response to a target stimulus requires multiple presentations of the stimulus and then an averaging of results using statistical averaging. This drowns out other brain activity not related to the presentation of the stimulus.
Strength:
1. This method of examining the brain is advantageous as it enables determination of how processes are affected by specific experimental manipulations. Making ERP use a more experimentally robust method as it can eliminate other extraneous neutral activity which other techniques may struggle to do.
