The Biological Area

Question 1

What are the studies in the biological area and how are they paired

Answer 1

Classic: Sperry (1) and blakemore and Cooper (2) contemporary: Casey (1) and maguire (2)

Question 2

What is the background for Sperry study

Answer 2

Patients who had severe epilepsy had a comissurotomy operation where the corpus callosum / commissural fibres between the 2 brain hemispheres were cut to contain seizures to one hemisphere.

Question 3

What were the aims for sperrys study

Answer 3

To investigate the effects of de connection and show that each hemisphere has a different function, also wanted to map Lateralisation of brain function (each hemisphere controls a diff half of the body)

Question 4

What was the research method for sperrys study

Answer 4

Quasi experiment as having epilepsy was a naturally occurring iv, case study as studying a small group (11) in detail and observation and observed how they did in certain tasks

Question 5

What was the sample for sperrys study

Answer 5

11 male and female patients who had a commissurotomy to treat epilepsy, all from America

Question 6

Describe the method for sperrys study

Answer 6

Equipment was used to allow various types of sensory information to be presented to one hemisphere or both. A tachistoscope was used to present an image to one side of a screen or both for one tenth of a second (to stop eye moving and both hemispheres getting info). One eye was covered to prevent eye from seeing both visual fields and they were told to look at a fixation point in centre of screen. Tactile information would be presented to either left or right hand or both, the hands may be hidden from view behind a screen Participants were in silence unless asked a question to prevent info being passed to both hemispheres via both ears.

Question 7

What were the findings for sperrys study and conclusion

Answer 7

When objects were presented to the right visual field, information went to left hemi and the p could say what they saw and could draw it with their right hand (as left had language and controls right side of body). When objects presented to L visual field, info went to R hemi so they could draw what they saw with left hand but couldn’t say what they saw. When diff stim presented to diff visual fields (like apple to left, key to right), apple went to R hemi and key to L, so can draw apple W L and say key but can’t say apple. When math prob into L.v.f, info went to R hemi so could solve by pointing with L and R process math info. When nude image presented to L, went to R hemi, they would laugh/blush but couldn’t say what they saw. When objects felt by r unseen, went to L hemi so could say, when felt with L unseen, went to R so could find by touch w L but not say. Conc: brain does have lateralisation of function

Question 8

What is the background for blakemore and coopers study

Answer 8

Hirsch and spinelli investigated the visual cortex of kittens where they had goggles so that they could only see horizontal stripes on one eye and vertical in the other. When they goggles were removed, kittens showed visual deficits and their visual neurones had adapted to environments in each eye. This suggested they show plasticity (how brain changes according to environment)

Question 9

What is the aim of B&C study

Answer 9

To investigate the effects on kittens in being raised in a restricted visual environment on kittens. Interests in effect of environment on behaviour and investigate the neurophysiological effects in neurones on the visual cortex

Question 10

What is the research method of B&C study

Answer 10

Lab experiment as had iv of vertical or horizontal and controlled environment. Case study as a small number of cats were studied in detail. Observation as kittens behaviours were observed and longitudinal as studied same kittens over 1 year and independent groups o

Question 11

Sample for B&C study

Answer 11

Kittens from birth to one year old

Question 12

Method for B&C study

Answer 12

From birth to 2 weeks, the kittens were in a completely dark room. From two weeks to five months, kittens spent five hours a day in cylindrical apparatus which had a clear glass platform and either horizontal or vertical black and white stripes. Kittens wore a black collar so could only see the stripes. From 5 months, kittens were taken for several hours a week to a well lit room with chairs and tables and their behaviour was observed

Question 13

What were the findings from B&C study

Answer 13

When first exposed to the well lit room, the cats showed visual deficits as showed no startle response when object or hand thrust towards them and had no visual placing (putting paws out in anticipation towards edge of table and only did when felt it), navigated around room by touch. After 10 hours of exposure to room, deficits disappeared and began to show visual placing, startle responses but visual tracking was clumsy and jerky and tried to reach for objects far away and bumped into things and they were virtually blind to lines they did not see in the cylinder when rod shaken in front of them. 2 cats that were operated on also showed their visual neurones had preferred orientations with horizontal raised having no neurones in vertical orientation and vice versa

Question 14

Conclusions of B&C study

Answer 14

Differences between kittens suggests neurones can change preferred orientation according to stimulation they receive (shows brain plasticity)

Question 15

What is the background for Caseys study

Answer 15

Mischel developed the marshmallow test to test the ability to delay gratification (resist reward now for a greater one in the future)where 4 year old children in the 60s were taken individually to a room with no distractions where they were told they could eat one marshmallow immediately but if they could wait and not eat if for 15 minutes then they could have 2 marshmallows. Those unable to wait were low delayers and those who could were high delayers

Question 16

What is the aim for Casey study

Answer 16

To find out if ps who were low delayers on the marshmallow test when they were 4 and also reported low self control on psychometric measures in their 20s and 30s would show more errors on a go no go task if the stimuli were hot (rewarding emotional faces) than those who were high delayers. Also that low delayers would show lower activity in inferior frontal gyrus (pfc) and higher in the ventral striatum and high delayers

Question 17

What was the sample for caseys study

Answer 17

562 ps participated in the original marshmallow test when they were 4, out of those, 155 were tested on self control in their 20s and 135 in their 30s. Out of these 117 were consistently high or low delayers and they were contact and 59 agreed to be tested (27 low delayers, 16f and 11m and 32 high 20f and 12m) aged 44

Question 18

What is the method for caseys study 1

Answer 18

Experiment 1: self control was measured by using a go no go task where so had to either press a button or not press it according to diff stimuli. 59 ps each did 4 go no go tasks where faces were shown on a laptop in their own homes for 500ms with 1s intervals. Cool task involved pressing a button (go) or not pressing (no go) for either male or female neutral faces, the hot task ps were told to press button when they saw fearful faces but not to when they saw happy faces as happy faces would be a rewarding stimulus compared to neutral.

Question 19

What were the results for Caseys study in experiment 1 and the conc from this

Answer 19

Both groups made more errors on the no go tasks compared to go but whereas they made similar no. Errors on the cool task, low delayers made more errors on the hot task (worse at resisting pressing go when they saw a happy face) compared to high delayers. When no go for happy % errors for low Ds was 15.7% compared to 11.2% for high Ds whearas when no go for fearful % errors for low - 12% and 10.4% for high. Conc= self control remains consolidate

Question 20

What was the Method for caseys study 2 and findings

Answer 20

Out of 59 from study 1, 27 agreed to take part (11 low Ds, 15 high Ds). While inside an fMRI scanner, ps took part in similar go no task but there was a mean delay for 5.2s in between pics whilst ps focused on central cross hair. There were 48 trials each 35 to 13 no go.. stimuli were presented on screen in scanner and a diff button was used. Found when low delayers saw happy faces, they had less activity in inferior frontal gyrus (which control behaviour) and low Ds had more activity in the ventral striatum (part of the limb if system associated with rewards

Question 21

What was the conc for caseys study

Answer 21

Resisting temptation is a stable characteristic and delay ability is hindered by alluring cues. Also provides evidence to cool and hot processing systems as hot in ventral striatum and cool in pfc

Question 22

What is the background for maguires study

Answer 22

The hippocampus is a region of the brain involved in spatial memory and in some species of animals ‘hippocampal volumes enlarge during seasons when demand for spatial ability is at its greatest’ which suggests that the hippocampus has plasticity

Question 23

What is the aim for maguires study

Answer 23

To investigate the differences in the hippocampus in London taxi drivers compared to controls to see if it shows plasticity is volume. Also aimed to further investigate functions of hippocampus in spatial memory

Question 24

What is the sample and sampling method in maguires study

Answer 24

16 right handed London taxi drivers aged 32-62 years gathered via self selecting as they came forward after being told about the study taking place. They were chosen as they have to learn the knowledge (every road in a six mile radius of Charing Cross so have a greater demand for spatial memory) all had been taxi drivers for 1 and a half years since completing the knowledge and had generally healthy medical profiles. Control group was 50 right handed males aged 32-62 who were scanned for the mri database at welcome department of cog psych at UCL.

Question 25

What was the procedure for maguires study

Answer 25

Taxi drivers brains were scanned in mri, scans were compared to controls and measured brain diffs using voxel based morphometry (VBM) to measure grey matter (volume) in hippocampus in a 3D measurement and pixel counting which was carried out by a person experienced in technique and blind to ps identity (also 2D method to look at differences in posterior and anterior hippocampus. (Area)

Question 26

What were the findings from maguires study

Answer 26

Pixel counting analysis found the was no diff in the overall vol of the hippocampus between taxi drivers and controls but showed the right anterior hippocampus had higher vol for non taxi drivers and taxi drivers had higher vol in posterior hippocampus than control. VBM showed in taxi drivers there was an increase in grey matter in the left and right hippocampi (bilaterally) of posterior but decrease in anterior. The also found a + correlation between the volume of grey matter in the posterior hippocampus and the length of time as a taxi driver and a - correlation between length of time as a taxi driver and vol grey layer on anterior hippocampus

Question 27

Conclusions of maguires study

Answer 27

The human brain (hippocampus) has plasticity that that changes can occur in line with demands placed on taxi drivers by their job

Question 28

Sim and diffs for sperry and Casey

Answer 28

Sim: both had highly controlled lab experiments, both looking at specific regions of the brain, both conducted ethically, both hard to establish reliability diffs: sperrys had abnormal brains so Casey more generalisable, Casey was longitudinal, Casey had fmri

Question 29

Sims and diffs for b&c and maguire

Answer 29

Sim: highly controlled lab experiments, both used objective measures, gathered quantitative data, diffs: maguire on the human brain, b&c on kittens, maguire was snapshot, maguire studying hippocampus, b & c neurones.

Question 30

How Casey has changed understanding from sperry and how changed understanding of ind, soc and cult diversity

Answer 30

Has: individual diffs on brain structure which could influence behaviour, tells us about roles of other parts of the brain (v.S I.f.g), fora compared to cc. Hasn’t: hasn’t changed understating of corpus callosum, hasn’t on cult diversity as in us. Ind: ind diffs in brain structure which could effect response to tempting stim. Social hasn’t: not investigating social factors as brain based on biology cult hasn’t : both took place in us but brain doesn’t look at cultural affects

Question 31

How maguire has changed our understanding since b&c -nothing for ind, soc and cult as can’t compare animals to humans

Answer 31

Has: shows brain plasticity can occur in humans as well and can happen in hippocampus not just neurones. Hasn’t: no change to understanding of plasticity in visual neurones