biological psychology- paper2 Flashcards
what are the assumptions of the biological approach.
everything psychological is at first biological.
how biological structure and processes within the body impacts on behaviour.
all behaviour is down to the brain, genetics, neurochemistry.
what are the 4 concepts of the approach
genetic, evolution, brain regions, brain activity.
what is the group of connections between the hemispheres called
corpus callosum.
what is the surgery called which splits hemispheres
commissurotomy.
what is lateralisation of function
hemispheres ( brain works in opposites)
what is localisation of function
brain regions.
what is the aim of Sperry ?
to investigate the psychological effects hemispheric disconnection has in patients with severe epilepsy.
what is the method ?
controlled observation, snapshot, quasi- brain already halved.
IV: presence or absence of split brain.
DV: performance on various visual and tactile tasks.
what is the sample?
11 split brain patients, LA, opportunity sample from the white memorial centre.
(no culture bias - everyone has a brain )
what are the materials used in sperry?
tachistoscope- projects behind screen and flashes image for 0.1 seconds. they can reach objects but can’t see them.
what is task 1
(verbal)
visual stimulus was presented to either left or right visual filed. then shown to other and asked if they recognise object
what is task 2
(verbal)
shown stimuli to left and right hemisphere and asked to describe it .
what is task 3
(written)
shown stimuli to left and right hemisphere separately then asked to write what they saw.
what is task 4
(tactile/pointing)
shown stimuli to left and write hemisphere separately then asked to point at it.
what is task 5
(draw)
stimuli presented simultaneously (same time) to LH and RH. asked to draw with left hand.
what is task 6
(tactile)
words composed of 2 words (half on LH and half on RH ) asked to identify in 3 ways: search for object under screen, say it , write it.
what is task 7
( tactile)
object placed in hands and asked to say/ write the name of it.
what is the left and right hemisphere responsible for.
left- language
right- emotion
what are the results ( L/R visual field)
right visual field- ( goes to left hemisphere) describe, point and find with right hand.
left visual field- ( goes to right hemisphere)
can’t name, point or find with left hand.
what is a conclusion of sperry
hemispheres are independent and have responsibilities.
multiple processing can occur (dual)
supports bio approach ( brain regions )
what is the background of Casey
cognitive control- resisting temptation
known as marshmallow test
cooling strategies- supress temptation and reduces appeal of reward.
hot cues-desire for something( emotional)
cool cues- takes emotion away
Metcalfe and mischel: cooling system- decision making, called inferior frontal gyrus- more active in high delayers.
ventral striatum- active in low delayers.
what is the aim of exp1- cognitive test
to investigate if people who were low delayers in original marshmallow test would still have low self-control in 40s.
what is the method of casey
quasi
iv - high delayers, low delayers
dv- number of errors on the go/ no go task
what is the procedure of exp 1
go and no/go task
go- push button because of hot cue eg. happy face.
no go - no button, cool cue eg. neutral happy.
how was casey standardised
each did 4 tasks at home with a computer provided to them ( not high in EV as you don’t press buzzers at home )
shown for 500 ms with 1 sec intervals.
what is the sample of casey
562 ppts
1993, 20’s, 155 ppts
2003, 30’s 135 ppts = self report
*59 tested, 27- low delayer, 32- high delayer
exp1- results
ppts who can delay gratitude as a child can delay gratitude as an adult.
no difference between high/low delayers in terms of reaction time.
in the no go trials low delayers made more errors on hot task.
experiment 2 aim
to investigate if regions of the brain predicted delay of gratification.
procedure of exp2
used FMRI scan doing same tasks but was a 2-14.5 delay between presentation.
sample of exp 2
26 out of 59 in scanner.
repeated measures as go no/go task again but in scanner.
results of exp2
both groups scored highly on accuracy.
low delayers showed reduced activity in the right inferior frontal gyrus than high delayers.
conclusions
localisation of function
if you delay gratification as a child you can as an adult.
‘hot and cold’ cues effect self-control
what is the background of Blakemore and cooper
-visual cortex- Hubel and Wiesel stimulated individual neurons in visual cortex and found that their are columns of cells that responds to particular orientations so at 45* only one column will detect line.
-can orientation change because of environment? Hirsch and Spinelli- raised cats with one eye exposed to vertical one eye horizontal and found cells now monocularly driven.
what is aim 1 of Blackmore and cooper
-to investigate further the physiological and behavioural effects of restricted early visual experience on the development of cells of visual cortex
what is aim 2
consider if brain development/plasticity occurs due to nurture rather than nature
what is the method
lab experiment, independent measures.
what is the IV/DV
IV- horizontal or vertical environment
DV- behavioural and neurological differences between vertical and horizontal cats environments
what is the sample
two cats one in vertical and one in horizontal environment
tested: behavioural- 5 months
neurological- 7.5 months
what are the materials used
cylinder with glass base either horizontally lined or vertically.
kittens had back colour to prevent them seeing their body.
what happened in the first 2 weeks and then the second week in the procedure
first 2- in a dark room with binocular vision
2 weeks old- placed in a cylinder for 5 hours a day.
what was important about the cats at 5 months old.
critical period as visual systems are fully developed so can change.
what happened after 5 months for the cats
for several hours a week they would be placed in a well-lit room with chairs and tables.
given lenses so astigmitation wasn’t a problenm
how was their behaviour test measuring
cats initial responses to new visions were observed and watched over the following weeks.
what were the behavioural testing results
some reflexes were normal. temporary deficit- visual placing was not shown and took 10 hours for cats to recover permanent deficit- cat reached out for objects far away
what is the neurophysiological test and when was it done.
at 7.5 weeks cats were anesthetised and temporarily paralysed and played with rod
electrode was inserted into columns of neurons to measure electrical firing when showed lines of preferred orientation
what were the results of the neurophysiological test
-if rod was shaken horizontally then cats from horizontal environments would react
- only 12 out of 52 neurons responded within 45* of preferred orientation
-75% of cells were binocular
what are the conclusions
-nature (visual cortex) is modified by nurture ( environment) so is interactionist ( both)
- unused parts of innate nervous system don’t degenerate but adapt to environment
- cats visual cortex does change shaped based on V or H environment ( plasticity )
what is the background for Maguire
hippocampus is a key role in spatial memory and navigation.
size of hippocampus in animals is species dependant
black cab drivers have to pass a knowledge test with 80 written routes and any verbal out of 240 others
what is the 1 st aim of Maguire
1- to investigate the roll if hippocampus in spatial memory and navigation and if the brain shows plasticity for black cab drivers
what is the second aim of Maguire
if thee is a relationship between length of taxi-driving experience and measure of grey matter in the hippocampus
what is grey matter
groups of neurons
what is the sample
16 licensed taxi-drivers matched to comparison group
both right handed, variety of ages, all healthy
what is the comparison group
50 non-taxi drivers, right-handed, all male, used same scanner
what is the method
quasi experiment- already licensed taxi-drivers
indendant meaures as one group is taxi-drivers but one is not.
what are the IV’S and DV’S
IV: taxi-driver, non-taxi driver
DV- volume of hippocampus
what is the procedure
used the same structural MRI
analysed by 2 techniques- VBM ( voxel- based- morphometry)
pixel counting- how many dots are at one singe point at both anterior and posterior hippocampus
experimenter was blind ( didn’t know who was taxi driver)
what are the controls
all used same MRI scanner
experimenter- blind
matched sample
what are the results of aim 1
taxi drivers have higher volume of grey matter in their right posterior hippocampus and opposite for non-taxi drivers
what are results from aim 2
there is a positive correlation - longer time being a taxi-driver the increased grey matter in right posterior hippocampus
what is a conclusion
experience of taxi-driving can change brain plasticity ( volume of hippocampus)
