Biopsych

Question 1

what is fMRI ?

Answer 1

• measures changes in blood flow of the brain when person performs task
• produces 3D images
• most active neurons = most blood flow

Question 2

what is an EEG ?

Answer 2

• electrodes placed on the scalp
• measures electrical activity
• can detect epilepsy

Question 3

what is ERP ?

Answer 3

• type of brainwave that are triggered by certain events
• all extraneous brain activity from original EEG is filtered to isolate specific neural responses

Question 4

what is postmorten ?

Answer 4

• after death brain studied for abnormalities

Question 5

Strengths of fMRI

Answer 5

• non-invasive + risk free cause it does not use radiation
• high spatial resolution = provides clear pic of how brain is localised

Question 6

Weakness of fMRI

Answer 6

• poor temporal resolution = 5 second time-lag between neuron firing and detection
• can only measure blood flow so cant see individual activity of neurone so difficult to tell what kind of activity is shown . therefore not truly a quantitative measure of brain activity

Question 7

strengths of EEG

Answer 7

• high temporal resolution
• can diagnose epilepsy = clinical applications

Question 8

weakness of EEG

Answer 8

• cannot pinpoint exact source of neural activity

Question 9

strength of ERPs

Answer 9

• higher temporal resolution than fMRI + EEG which has lead to widespread use in measuring cognitive functions

Question 10

weakness of ERPs

Answer 10

• lack of standardisation of procedures
• difficult to eliminate all extraneous variables + noise so pure data cannot be obtained

Question 11

strength of post-mortem examinations

Answer 11

• useful before tech was developed = used by Broca’s + Wernicke’ a

Question 12

weakness of post-mortem examinations

Answer 12

ethical issues = p’s may not be able to give informed consent if they have rare disorder etc eg. HM brain was studied after death but he lost ability to form new memories

cannot establish cause + effect = because observed damage may be unrelated to behaviour

Question 13

what are the 4 lobes of the brain ?

Answer 13

frontal
parietal
temporal
occipital

Question 14

what is Broca’s area and where is it located ?

Answer 14

• responsible for speech production
• located in left frontal lobe

Question 15

what is Wernicke’s area ?

Answer 15

• responsible for comprehension (language understanding)
• located in temporal lobe

Question 16

what is Broca’s aphasia ?

Answer 16

• cannot produce speech but can understand + convey meaning

Question 17

what is Wernicke’s area ?

Answer 17

• can produce speech but not convey meaning

Question 18

Outline one difference between the EEG and ERPs (2)

Answer 18

EEG is a recording of general brain activity usually linked to states such as sleep and arousal, whilst ERPs are elicited
by specific stimuli presented to the participant

Question 19

Explain why neurons can only transmit information in one direction at a synapse (3)

Answer 19

• synaptic vesicles containing the neurotransmitter are only present on pre-synaptic membrane
• receptors for the neurotransmitters are only present on the postsynaptic membrane

diffusion of the neurotransmitters mean they can only go from high to low concentration,

Question 20

what is an excitatory neurotransmitter ?

Answer 20

increase in neurones +ve charge , increases likelihood of post-synaptic neuron firing an impulse

Question 21

what is an inhibitory neurotransmitter ?

Answer 21

increase in -ve charge, decreases likelihood of post-synaptic neuron firing an impulse, eg. GABA

Question 22

what is summation ?

Answer 22

excitatory and inhibitory influences are summed, if the net effect on the post synaptic neuron is inhibitory, the neuron will be less likely to ‘fire’ and if the net effect
is excitatory, the neuron will be more likely to fire.

Question 23

Outline the difference in function between Broca’s area and Wernicke’s area (2)

Answer 23

brocas = speech production , wernickes’s area = langauge production
broca’s enables speech to be fluent wheras wernickes allowa speech to be meaningful

Question 24

What is the role of the somatic Nervous system (2)

Answer 24

transmits sesnory information from receptors to CNS
info via brain to effectors to produce voluntary movements