Biopsychology

Question 1

Outline the role and divisions of the nervous system

Answer 1

nervous system collects, processes and responds to information from the environment
nervous system coordinates different cells and organs in the body
split into central and peripheral nervous systems

Question 2

Outline the function and divisions of the CNS

Answer 2

made up of the brain and spinal cord

spinal cord responsible for reflex actions and passes messages to and from the brain and connects nerves to PNS

Question 3

Outline the functions and divisions of the PNS

Answer 3

Sends information from receptors to CNS
Sends information from CNS to effectors
consists of autonomic and somatic nervous systems
ANS is involuntary and governs internal organs
SNS is responsible for muscle movement
ANS consists of sympathetic (fight or flight increased arousal)
parasympathetic (rest and digest) divisions.

Question 4

Define hormones, outline the function of the endocrine system and ways in which it differs from the nervous system

Answer 4

hormones= chemical messengers released into the bloodstream
endocrine system instructs glands to release hormones
endocrine system is much slower than the nervous system (its effects)
but has more general, widespread effects.

Question 5

Outline the SAM pathway and when it occurs

Answer 5

Deals with acute stressors

1) stressor is recognised by the hypothalamus
2) hypothalamus activates the sympathetic NS
3) adrenal medulla is activated and pituitary gland stimulates the release of adrenaline
4) results in a high state of arousal to prepare body for fight or flight

Question 6

Outline the effects of adrenaline/ the sympathetic nervous system being activated

Answer 6

• increased heart rate, blood pressure and respiration
• increased oxygen supply to brain and muscles
• reduced salivation and digestion
• pupil dilation
• rectum contracts

Question 7

Outline the HPA pathway and when it occurs

Answer 7

Deals with chronic stressors

1) stressor is recognised by the hypothalamus
2) hypothalamus sends message to pituitary gland, causing the secretion of ACTH
3) ACTH travels to and stimulates the adrenal cortex, releasing corticosteroids into the bloodstream
4) this causes the liver to release energy and lowers pain sensitivity, but also supresses the immune system

Question 8

Define neurons and outline the structures and functions of the different types of neurons

Answer 8

neurons= nerve cells that transmit and process messages through chemical and electrical signals
sensory neuron: carries messages from PNS to CNS with long dendrites and short axons
relay neuron: connects sensory and motor neurons with short dendrites and short axons
motor neuron: connects CNS to effectors with short dendrites and long axons

Question 9

Outline the structure of a neuron

Answer 9

nucleus=genetic info
dendrites: carry impulses towards cell body
axons: carry impulses away from cell body
myelin sheath: protects/insulates axon and increases synaptic transmission
nodes of Ranvier: force impulses to ‘jump’ across gaps to increase synaptic transmission
axon terminal: communicate with the next neuron across the synapse

Question 10

Outline the process of synaptic transmission

Answer 10

1)action potential travels along cell body and triggers the release of neurostransmitters from pre-synaptic vesicles once it reaches the axon
2)neurotransmitters diffuse across the synapse and bind to receptor sites
3)once the receptor sites have been activated, this can result in either an excitatory or inhibitory effect on the post-synaptic cell
(4=some reuptake from pre-synaptic cell)

Question 11

Define excitation and inhibition

Answer 11

• excitation: when a neurotransmitter increases the positive charge on the post-synaptic neuron, resulting in an increased likelihood that the neuron will fire and pass on the electrical impulse
• inhibition: when a neurotransmitter causes a negative charge on the post synaptic neuron, resulting in a decreased likelihood that the neuron will fire and pass on the electrical impulse

Question 12

Outline what is meant by localisation of function as well as the different regions of the brain

Answer 12

-the idea that different areas of the brain are responsible for different functions (cortical specialisation)
frontal lobe: motor area that controls voluntary movement on the opposite side of the body
parietal lobe: integrates sensory information and knowledge of numbers; deals with sensory info in relation to location
somatosensory cortex: sensory info. from skin; large amount of cortex devoted to a body part= increased sensitivity in that area
occipital lobe: visual cortex at back of brain
temporal lobe: auditory area that analyses speech-based info

Question 13

What are the functions of Brocha’s and Wernicke’s areas?

Answer 13

Brocha’s area linked to speech production (Brocha’s aphasia characterised by slow speech lacking fluency)
Wernicke’s area linked to language comprehension

Question 14

Evaluate localisation of function

Answer 14

brain scan evidence: Peterson et al (1988) found Brocha’s area active during reading task and Wernicke’s area active during listening task
Tulving et al found semantic and episodic memories reside in different areas of the pre-frontal cortex
case study evidence such as ‘Tan’
refuting research by Lashley: removed 10-50% of the cortex in rats’ brains and got them to learn a maze and found no part of the cortex was more important than the other in achieving this goal, and the process of learning appeared to require all parts of the cortex
However, generalisability issues are present with animal research

Question 15

Explain what is meant by plasticity and synaptic pruning

Answer 15

plasticity is the brain’s ability to functionally and physically change and adapt as a result of new learning and experiences
synaptic pruning is when frequently used synaptic connections and strengthened and rarely used ones ‘deleted’ or lost

Question 16

Outline supporting research for plasticity

Answer 16

• Maguire et al (2000) scanned brains of taxi drivers who had taken ‘The Knowledge’ test vs a control group and found a higher volume of grey matter in the posterior hippocampus + a positive correlation with experience in job and amount of grey matter
• Draganski et al (2006) scanned brains of medical students three months before and three months after their final exams and found that learning induced changes occurred in the posterior hippocampus and the parietal cortex

Question 17

Explain what is meant by functional recovery and how this process occurs after trauma

Answer 17

functional recovery is a form of plasticity whereby the brain redistributes functions usually performed by damaged areas to undamaged areas of the brain following trauma

• brain can form new synaptic connections close to the damaged areas
• secondary neural pathways not typically used for that function would be activated to enable functioning
• axonal sprouting= the growth of new nerve endings connecting to undamaged nerve endings to form new neural pathways
• reformation of blood vessels
• recruitment of similar areas of the brain on the opposite side to perform the task; over a period of time functionality may then shift back to the other side

Question 18

Evaluate plasticity and functional recovery after trauma

Answer 18

• practical applications to neurorehabilitation that aim to counter the possible effects that occur after trauma; shows that although the brain has the ability and capacity to ‘fix itself’, further intervention is needed for it to be fully successful
• negative effects of plasticity can occur, where the brain rewires itself with maladaptive effects such as phantom limb syndrome, believed to be the result of cortical reorganisation in the somatosensory cortex when limb loss occurs and results in sensations experienced in the missing limb as if it were still there.

Question 19

Outline research into hemispheric lateralisation

Answer 19

Sperry (1968): conducted research on patients who had their corpus callosum removed/cut down middle

• used a split visual field where separate words appeared on the left and right visual field
• (info from RVF is processed by the left hemisphere)
• found that if word was shown in RVF, pps could easily describe what they had seen (as a result of the presence of language centres in the left hemisphere)
• if shown in the LVF, it was often reported that nothing was there
• left hand was able to select objects from a grab-bag behind the screen that was most associated with word
• words from LVF could be written with right hand

Question 20

Evaluate research into hemispheric lateralisation

Answer 20

• highly standardised procedures (0.1 second flash)
• small, unique sample used; all experienced epileptic seizures that arguably may have caused unique neural changes that influenced the findings, therefore resulting in a questionable validity; unrepresentative sample=generalisability issues to target population
• some pps surgery resulted in more disconnection between the hemispheres than other pps

Question 21

Outline and evaluate fMRI

Answer 21

measures changes in blood flow and oxygenation in the brain as a result of activity in particular regions
used while pps conduct a task and produces 3D images
-helps to further our understanding of localisation
-no radiation and high spatial resolution
-poor temporal resolution (5 second lag)

Question 22

Outline and evaluate EEGs

Answer 22

measures electrical activity in the brain using electrodes fixed onto the scalp
measures brainwave patterns generated from neurons used as a diagnostic tool for arrhythmic activity patterns
-high temporal resolution
-gives on overly-general measure of brain activity; cannot pinpoint exact source of activity

Question 23

Outline and evaluate ERPs

Answer 23

takes raw data from EEGs and performs statistical analysis in order to see the brains electrophysiological response to specific events/stimuli; analysis isolates these desired responses from EEG data

• provides more specificity than than raw EEG data
• in order for complete success, all background noise and extraneous variables must be eliminated, which is extremely difficult

Question 24

Outline and evaluate post-mortem examinations

Answer 24

involves the analysis of the brain after death to see if abnormal behaviours displayed throughout a person’s lifetime can be linked to neural abnormalities

• provides a basic foundation of understanding of the brain and basic links
• correlation not causation; direction of influence unclear

Question 25

What are biological rhythms?

Answer 25

-biological rhythms are distinct patterns of changes in the body that conform to a cyclical time period

Question 26

What is a circadian rhythm? Give an example and a piece of supporting research

Answer 26

circadian rhythms follow a 24-hour cycle
e.g: the sleep/wake cycle
Siffre’s Cave Study:
-spent extended periods underground to study his own biological rhythms
-found that when spending 6 months in a Texan cave, his biological rhythm was just beyond 24 hours (around 25) and that he slept and woke on a regular schedule

Question 27

Evaluate what research has shown about circadian rhythms

Answer 27

practical applications to night workers in shift work found to have a reduced concentration at around 6am (a circadian trough)
practical implications into how to best manage worker’s productivity in an economic way
practical applications to drug treatments; research into circadian rhythms has found that there are peak times during the days and nights
small sample case studies
poor control in cave studies
individual differences in people’s sleep/wake cycles

Question 28

What is an infradian rhythm? Give an example and piece of supporting research

Answer 28

infradian rhythms follows a cycle that lasts less than 24 hours
e.g: menstrual cycle or seasonal affective disorders
Stern and McIntlock:
-found how although menstruation is an endogenous process, it can be influenced by exogenous ones such as female pheromones

Question 29

Evaluate what research has shown into infradian rhythms

Answer 29

• arguable an evolutionary basis of menstrual synchrony, so that women fall pregnant around the same time and the offspring can be cared for by a larger social group
• too many confounding variables that could effect menstrual synchrony
• other studies failed to find any evidence of menstrual synchrony in all-female samples
• effects of pheromones largely obtained from animal studies

Question 30

What is an ultradian rhythm? Give a detailed example

Answer 30

ultradian rhythms occur with a frequency of more than one cycle in 24 hours

e. g: the stages of sleep
- light sleep starts with slow alpha waves and becomes even slower and deeper theta waves
- deep sleep involves delta waves
- REM sleep where brain activity speeds up significantly even though the body is paralysed, resembling the awake brain; REM correlated with dreaming

Question 31

What are endogenous pacemaker and exogenous zeitgebers?

Answer 31

endogenous pacemakers are internal body clocks which regulate biological rhythms (SCN suprachiasmatic nucleus)
exogenous zeitgebers are external factors/cues that may affect our biological rhythms, such as light affecting the sleep/wake cycle

Question 32

Outline a piece of research into the suprachiasmatic nucleus

Answer 32

DeCoursey et al: destroyed the SCN connections of 30 chipmunks and observed their behaviour when returned to their natural habitat for 80 days
-found that their sleep/wake cycle had disappeared and a large proportion of them had been killed

Question 33

What does the suprachiasmatic nucleus do to induce sleep?

Answer 33

SCN passes information about day length and light to the pineal gland.
The pineal gland increases the production of melatonin during the night; melatonin induces sleep and is inhibited during periods of wakefulness