Biopsychology

Question 1

Briefly outline the types of neuron

Answer 1

Motor- carries messages from CNS to muscles and glands

Sensory- carries messages from the PNS to the CNS

Relay- carries messages from sensory to motor neurons or other relay neurons

Question 2

Describe the structure of a neuron

Answer 2

Contains a cell body
Dendrites which carry nerve impulses towards the cell body
Axon covered in myelin sheath to speed up message
Terminal buttons that communicate with the next neuron in the chain

Question 3

Describe a sensory neuron

Answer 3

Found in receptors
Carry nerve impulses from the PNS to the CNS
Translated into sensations when they reach the brain
Some stop at the spinal cord for reflex actions

Long dendrites and short axons

Question 4

Describe a relay neuron

Answer 4

Most common
Only found in the CNS
Connect sensory neurons to motor or other relay neurons

Short dendrites and short axons

Question 5

Describe a motor neuron

Answer 5

Carry messages from CNS and control motor movements
When stimulated, release neurotransmitters that bind to receptors on muscle and trigger a reaction
Muscle relaxation = inhibition

Short dendrites and long axons

Question 6

Describe synaptic transmission

Answer 6

Nerve impulse travels down the axon of a pre-synaptic neuron

End of axon, neurotransmitters are released from vesicles within the pre-synaptic neuron

These diffuse across the synapse

Neurotransmitters bind to receptors on the post-synaptic neuron

Stimulates post-synaptic neuron to transmit a nerve impulse down its axon, to the next neuron

Neurotransmitters deactivate by being reabsorbed back or being broken down by enzymes

Question 7

Describe excitation and inhibition

Answer 7

Inhibitory neurotransmitters result in the neuron becoming negatively charged and less likely to fire- inhibitory synapse

Excitatory neurotransmitters ie dopamine, causes neuron to increase its positive charge and making it more likely to fire.

Question 8

Describe summation

Answer 8

After receiving inhibitory and excitatory at the same time,
Combined and added up

Question 9

Describe the peripheral nervous system

Answer 9

Transmits messages via millions of neurons to and from the CNS.
Relay nerve impulses from the CNS to the rest of the body and from body back to CNS.

Divided into

Somatic nervous system-
Voluntary actions,
Senses- carry motor and sensory info to and from CNS

Automatic nervous system-
Vital functions
Carries only motor info to and from the CNS

Question 10

Describe the somatic nervous system

Answer 10

Controls voluntary actions
Carries sensory and motor information from the senses to the CNS and back

Part of the peripheral nervous system

Question 11

Describe the sympathetic nervous system

Answer 11

Involved in responses that help us deal with emergencies
Fight or flight

Neurons preparing the body for rapid action,
Release stored energy
Pupils to dilate
Slows down digestion and urination

Question 12

Describe the automatic nervous system

Answer 12

Involuntary/ vital actions
Eg, breathing, increasing heart rate

Carries only motor information from senses to and from the CNS

Divided into;

Sympathetic nervous system
Parasympathetic nervous system

Question 13

Describe the parasympathetic nervous system

Answer 13

Returning the body to a rest state once the emergency has passes
Rest and digest

Slow heartbeat

Bodily processes inhibited by sympathetic are returned to normal

Question 14

Describe the fight or flight response

Answer 14

After acute stressor,
Hypothalamus directs the sympathetic branch of ANS to send neurotransmitters to the adrenal medulla

Releases adrenaline into the bloodstream
And noradrenaline

Triggers physiological reactions

Question 15

What is meant by localisation of function

Answer 15

Specific functions have specific locations within the brain

If a certain area is damaged, the associated function will also be affected

Question 16

State 7 parts of the brain and where they are

Answer 16

Auditory cortex,
Temporal lobe either side of the brain

Motor cortex,
Back of the frontal lobe

Somatosensory cortex,
Next to the motor cortex, at the front of the parietal lobe

Visual cortex,
In the occipital lobe at the back of the brain

Broca’s area,
Left frontal lobe

Wernicke’s area,
Small area in left temporal lobe

Question 17

Describe support for localisation of function

Answer 17

Supported by case study evidence,
Man who could only say Tan. Broca performed an autopsy, found a lesion in a region of his brain,
Concluded that his aphasia was caused by damage to the area that controlled speech.
Increases validity,
H Lacks external validity, based on one individual
Phineas gage

Brain scan research

Peterson et al demonstrated how W’s area was active during listening tasks and Broca’s was active during a reading task.
Tulving et al
Episodic and semantic memories recalled from different sides of the prefrontal cortex whilst procedural in the cerebellum
Demonstrates how specific brain regions are active

Question 18

Define hemispheric lateralisation

Answer 18

The idea that these two hemispheres of the brain are functionally different,
Certain mental processes and behaviours are mainly controlled by one hemisphere rather than the other

Question 19

What connects the two hemispheres

Answer 19

Corpus callosum
Bundle of fibres
Communication pathway do that they can exchange information

Question 20

Loosely describe the left hemisphere

Answer 20

Language processing
Strokes often lead to speech impediments in broca or wernicke area

Question 21

Loosely describe the right hemisphere

Answer 21

Facial recognition
Spatial relationships

Question 22

Evaluate hemispherical lateralisation

Answer 22

Supporting evidence
Fink
PET scans to identify active areas during a visual processing task
Ps asked to attend to elements of an image, right hem active
Finer detail, left hem active
Tasks such as visual processing are feature of connected brain

Plasticity
When damaged, brain can adapt to reorganize itself to recover the function
Turk et al,
Brain damage to left hemisphere developed capacity to speak in right hem
Undermines lateralisation, can be distributed

Animal research
Lashley
Removed 10-50% of cortex in rats and got them to learn a maze
Found that there were no important areas
Suggests higher cognitive processes like learning are distributed holistically
Reduces validity of theory, challenges

Lateralisation may be further complicated by age
Szflarski
Language became more lateralised to the left hem as children developed,
After 25, lateralisation decreased with each decade
Suggests lateralisation is a more complex process, unanswered questions
Challenges how stable it is throughout our lives.

Question 23

Describe research into split-brain studies

Answer 23

Sperry
11 split brain patients

Procedure:

Verbal recognition-
A visual image presented to LVF with a tachistoscope.
Ps asked to describe what they had seen.
Repeated on RVF

Touch recognition-
Ps hands screened
Asked to pick up object with right hand and asked to describe.
Repeated with left

Findings:

Verbal recognition-
When picture shown in RVF, patients would easily describe.
If on left, reported there was nothing there
Bc
Lacked language ability to describe it

Touch recognition-
Able to select matching object from a bag with left hand.
In each case patient couldn’t verbally describe but could understand what the object was using right hem and select corresponding object accordingly

Question 24

Evaluate research into split-brain studies

Answer 24

Supports lateralisation
Image flashed quickly to make sure info couldn’t pass to other hem
Ensures research measured what it intended to
Methodology is high,y standardised, reliable, internally valid

Flawed
Only 11 patients used who had history of epileptic seizures and had drug therapy- unique sample
Problematic
Undermines validity, confounding variables, weaken reliability

Question 25

State 4 methods of studying the brain

Answer 25

fMRI EEG ERP Post mortem

Question 26

Describe functional magnetic resonance imaging

Answer 26

Detects changes in blood oxygenation and flow in the brain. When area of the brain active, consumes more oxygen as the haemodynamic response) Produces 3D images showing which part of the brain is involved in particular mental processes Shows activity 1-4 seconds after an event occurs Accurate within 1-2mm

Question 27

Evaluate fMRI

Answer 27

Less invasive, Don't use radiation or require insertion into the brain, Risk free Good spatial resolution 1-2mm Allows R to investigate brain regions with greater accuracy Expensive Require trained operators More difficult to organize, less attainable Low temporal resolution 1-4 seconds , worse than others Unable to predict with a high degree of accuracy the onset of brain activity

Question 28

Describe electroencephalogram

Answer 28

Places electrodes on Ps scalp to measure electrical activity in the brain Records brainwave patterns generated from millions of neurons Provides real time recording

Question 29

Describe Event-Rekated potentials

Answer 29

Uses a stimulus with the EEG to filter recordings leaving only event related potentials

Question 30

Evaluate EEG and ERP

Answer 30

Less invasive than other techniques like PET scans, Don't use radiation or inserted instruments Cheaper methods in comparison to fMRI, more widely available. Help to gather data leading to a greater understanding of sleeping and memory disorders High temporal resolution Takes readings every millisecond providing real time data. Accurate measurements Poor spatial resolution Only detect activity in superficial regions of the brain Unable to provide info on what is happening in deeper regions of the brain, Limited technique in comparison to fMRI

Question 31

Evaluate post mortem

Answer 31

Provide a detailed examination of the structure of the brain that aren't possible with scanning techniques Access regions otherwise struggled Useful for further research Ethical issues Consent and nether they provide it before death. Many carried out on severe psychological deficits like HM who would be unable to provide fully informed consent Causation Deficits may not be liked to those found in the brain. Could've been result of other illness. Other confounding variables, Medication , length of time between death and exam, age of person at death

Question 32

Describe brain plasticity

Answer 32

Brains capacity to change or adapt because of experience and new learning As we age, synaptic pruning occurs, rarely used synaptic connections are deleted, frequently used are strengthened

Question 33

Describe four methods of forming new synaptic connections

Answer 33

Axon sprouting- Growth of new nerve endings which connect with other undamaged nerve cells to form new neuronal pathways Denervation supersensitivity- Axons that do similar job become aroused to a higher level to compensate. This can make the area over sensitive to pain Recruitment of homologous areas- Similar areas on opposite side of the brain carry out function Neuronal unmasking- Dormant neurons open connections to regions that are not normally activated, Gives way to the development of new structures

Question 34

Evaluate plasticity

Answer 34

Evidence to support Maguire et al Used mri to scan London taxi drivers. Had greater posterior hippocampus, correlated with the time they had been a taxi driver Supports that the brain can adapt Demonstrates structural changes Evidence to support in animal studies Huber and Wiesel Kittens had eyes sewn up Brains cortical responses analysed Area with visual cortex not idle. It continued to process info from open info Supports that brain can adapt as result of experience Brain can reorganise neural connections Doesn't completely stop as we age

Question 35

Describe functional recovery

Answer 35

Unaffected areas are often able to adapt and compensate for those areas that are damaged. Type of neural plasticity The process can occur quickly after trauma and then slow down after several weeks or months. Then rehabilitation can be used to extend recovery. Axon sprouting- Roth of new nerve endings which connect with other undamaged nnerve cells to form new neuronal pathways Denervation supersensitivity- Occurs when axons that do a similar job become aroused to a higher level to compensate for the ones that are lost. - can make area over sensitive to pain Recruitment of homogulous areas- opposite side of the brain to perform specific tasks. E.g Broca's area damaged, right side would carry out function Neuronal unmasking- side of brain's neurons are dormant. Then unmasked to open connections in regions of the brain that are not normally activated.

Question 36

Evaluate functional recovery

Answer 36

practical applications Contributed to neurorehabilitation Physical therapy helps when recovery slows down. E.g. constraint-induced movement therapy is used with stroke patients. Repeatedly practice using affected part of their body while unaffected is restrained. Shows research is useful by helping professionals know when interventions need to be made. Demonstrates understanding of brain plasticity inform effective interventions. Improves outcomes for patients Cognitive reserve Affected by individual differences . Schneider et al- the more time people with brain injury had spent in education, greater chances of a disability-free recovery. 40% of DFR had more than 16 years education compared to 10% less than 12. Implies people with Britain damage who have insufficient DFR are less likely to achieve full recovery. Highlights role of cognitive reserve in functional recovery after brain injury. Indicates higher education have greater ability to recover. Factors affecting - Age Gender Existing disabilities Education

Question 37

Describe circadian

Answer 37

the sleep-wake cycle Happens every 24 hours Others - core body temperature follows a daily rhythm. Highest around 4pm and lowest at 4 am Hormone production- Hormones follow a circadian rhythm. E.g. production and release of melatonin from pineal gland peaks during hours of darkness, Activates chemical receptors in the brain, melatonin encourages feelings of sleep. Dark = more melatonin then drops when wake. Sleep wake cycle- Light and darkness are external signals that determine when we feel the need to sleep. Dips and rises ar different times of the day. Strongest sleep drive 2-4 am and 1-3 pm

Question 38

Describe research into circadian rhythms

Answer 38

Sniffer Live underground ina cave in Texas for 6 months with no external cues, e.g. daylight. Sleep-wake cycle settled into a 'free-running' rhythm of around 25 hours. Suggests endogenous pacemakers, scn , are important in controlling sleep-wake cycle. Despite absence of exogenous xeitgebers, suffer was able to maintain a relatively normal cycle. Folkard- Studied a university student, Kate aldcroft, volunteered to spend 25 days in the controlled environment of a laboratory. During her time, no access to daylight or other zeitgebers. Sleep wake cycle was extended to 30 hours.

Question 39

Describe infradian rhythms

Answer 39

Last more than 24 hours. E.g. menstruation, breeding, hibernation and seasonal affective disorder. Menstrual cycle- Governed by monthly changes in hormones that regulate ovulation. Typical cycle lasts 28 days. Rising levels of oestrogen cause ovary to release an egg. After ovulation, progesterone helps womb lining to grow thicker, readying the womb for pregnancy. If not pregnant, egg is absorbed into the body.

Question 40

Describe research into infradian rhythms

Answer 40

McClintock- 29 women with irregular periods. Samples of pheromones gathered from 9 women at different stages by cotton pads in armpits. Pads rubbed on upper lip of other participants. 68% of women experienced changes to their cycle bringing them closer to the 'odour donor;

Question 41

Evaluate research into infradian rhythsms

Answer 41

supported by theory of evolution. It would have been advantageous for women to menstruate and become pregnant at similar times. Allows babies who had lost their mothers during childbirth to have access to breast milk, improving chance of survival. Suggests that the synchronisation of menstrual cycle is an adaptive strategy. Many factors that may cause mentrual cycle change, e.g. stress, dieting and exercising.

Question 42

Describe ultradian rhythms

Answer 42

Last less than 24 hours. E.g. eye blinking, heartbeats, sleep patterns, breathing, pulse, appetite and digestion Stages of sleep: 5 stages lasting 90 minutes. 1- light sleep, easily woken. Alpha brain waves (high frequency, low aptitude) 2- light sleep continues. Sleep spindles(short bursts of activity) 3 and 4- deep sleep or slow wave sleep Delta waves (lower frequency, high amplitude) difficult to wake. 5- REM sleep. Body is paralysed yet brain activity closely resembles a woke brain. Theta waves. Eyes move around.

Question 43

Evaluate ultradian rhythms

Answer 43

has Improved understanding of age-related changes in sleep E.g. SWS reduces with age, leading to alertness in the elderly. Suggests knowledge has practical value Ignores individual differences Tucker- large differences in the duration of each sleep stage in many participants. Makes it difficult to describe 'normal sleep'

Question 44

What is meant by an endogenous pacemaker

Answer 44

internal body clocks that regulate many of our biological rhythms

Question 45

Describe the SCN

Answer 45

Suprachiasmatic nucleus Tiny bundle of nerve cells located in the hypothalamus. Maintains circadian rhythms e.g. sleep wake cycle. If it's damaged or destroyed, sleep becomes erratic. Lies above the optic chaism. Receives information about light directly from this structure. Continues even with yes closed, enabling biological clock to adjust to changing patterns of daylight whilst we are asleep. If biological clock is running slow, morning light automatically adjusts the clock, putting its rhythm in step with the world outside. This synchronisation is called entrainment

Question 46

What is meant by entrainment

Answer 46

The synchronisation of the SCN by changes in light

Question 47

Describe the pineal gland and melatonin as endogenous pacemakers

Answer 47

SCN passes information on day length and light to the pineal gland. During the night, increases production of melatonin - induces sleep and is inhibited during wakefulness. Linked to seasonal affective disorder.

Question 48

Evaluate endogenous pacemakers

Answer 48

supporting evidence Morgan- Hamsters If their SCN was removed, SW cycle disappeared . Transplanting scn cells from foetal hamsters into these hamsters helped to re-establish sleep wake cycle. If it was given a transplanted scn from a mutant strain with a shorter SWC of 20 hours, adopts same activity. Supports view that SCN is vital in maintaining the SWC. Provides strong evidence. Demonstrates importance in regulating circadian rhythms. However should be careful applying to humans. Social cues might influence human cycles. Difficult to generalise. Siffre- supports SCN. Lived underground in a cave in Texas for 6 months with no external cues. SWC settled into a 'free-running' rhythm of around 25 hours. Suggests endogenous pacemakers are important in controlling sleep wake cycle because he maintained a regular cycle. However only based on one individual case. His ma be different to general population, reducing external validity. Also used artificial lighting which may have acted as an extraneous variable, reducing internal validity Practical apps Circadian rhyths affect when drugs are most effective. TF when prescribed drugs it is now advised that they are taken at different times of the day to maximise effects. Suggests we have an internal body clock that controls SWC as medication is advised to be taken a round it. Highlights importance for understanding endogenous pacemakers in everyday healthcare practices, optimising treatment outcomes by aligning drug administration with body's natural rhythms Contradictory evidence- Folkard- Kate aldcroft- Spent 25 days in controlled environment. No access to any light or other zeitgebers that might have reset SCN. At the end, SWC had extended to 30 hours. Reduces validity of role of endogenous pacemakers bc exogenous xeitgebers are needed. Suggests external cues are crucial in synchronising.

Question 50

Descirbe exogenous zeitgebers

Answer 50

light Helps to maintain SWC by resetting the SCN. Receptors in SCN are sensitive to changes in light levels and use this to synchronise the activity of the bosy's organs and glands. Light resets the internal biological clock each day, keeping it on a 24 hour cycle.

Question 51

Describe social cues

Answer 51

mealtimes, bedtimes and social events. Research suggests that adapting to local times for eating and sleeping is an effective way of entraining circadian rhyth,s and beating jet lag when travelling long distances.

Question 52

Evaluate exogenous zeitgebers

Answer 52

Supporting evidence Campbell and Murphy- Shining light on the ack of p's knees shifted the circadian rhythm. Implies natural light plays a role in entraining our biological clocks to keep SWC synchronise with outside world. Demonstrates how external cues can influence timing of biological processes. Practical applications Treatments for jet lag- Burgess- Exposure to bright light prior to an east-west flight reduced jet lag. Ps who were exposed to bright light felt sleepier 2 hours earlier in the evening and woke up 2 hours earlier. Benefits economy as preventing jet lag improves productivity. E.g. people more likely to return to work after a flight. Shows how interventions can mitigate effects of jet lag . Contradictory evidence- Miles- Studied a young man who was blind from birth. Despite exposure to social cues, his SWC remained abnormal (24.9 hours) Suggests social cues alone aren't effective in resetting biological rhythm. Suggests other factors e.g. light play a more crucial role