Biological Area

Question 1

What are the assumptions of the Biological Area?

Answer 1

• All that is psychological is first physiological
• All behaviour has a biological cause, such as hormones, genetics, brain structure or neurochemicals
• The mind resides in the brain and so all thoughts, feelings and behaviours have a biological cause.

Question 2

What are the key themes within the Biological Area and name the 2 studies within each theme.

Answer 2

Regions of the Brain
* Sperry
*Casey

Brain Plasticity
* Blakemore and Cooper
* Maguire

Question 3

How are Sperry and Casey similar in their Research Methods?

Answer 3

Both studies used a quasi experiment. In Sperry’s study, the IV was whether the participant had a split-brain or not. In Casey’s study, the IV was whether the participant was a high or low delayer. Therefore in both studies, the IV was naturally occurring and was not manipulated by the experimenter.

Question 4

How are Sperry and Casey similar in their Practical Applications?

Answer 4

Both studies have practical applications. Sperry’s study provides evidence for lateralisation of brain function, showing that the 2 brain hemispheres have distinct roles e.g. left hemisphere controlling right side of body, right visual field and logic, right hemisphere controlling left side of body, left visual field and creativity. This has practical applications in the treatment of epilepsy and shows the effects of commissurotomy procedure. Casey’s study about delay of gratification tells us that an individuals ability to delay gratification is due to the activity in their Ventral Striatum and Inferior Frontal Gyrus. This can help us to understand addictions and provide treatment for people with addictions.

Question 5

How are Sperry and Casey similar in their Ethics?

Answer 5

Both studies are ethical as in both, participants gave informed consent and were protected from harm. In Sperry’s study, the split brain patients had already undergone the split-brain surgery for medical reasons prior to the study. In Casey’s study, the brain scans were non-invasive and the tasks were simple and caused no harm or distress.

Question 6

How are Sperry and Casey different in their Data Collected?

Answer 6

Sperry gathered qualitative data whereas Casey gathered quantitative data. Sperry produced qualitative data by describing what participants could and could not do in relation to visual and tactile tasks, e.g. information presented to the left visual field could not be described in speech or writing. Casey produced quantitative data as they measured the score in the Go No-go task and the fMRI scanner data. For example, in the hot go no-go task, low delayers made more false alarms/errors
(14.5%) compared to the high delayers (10.9%)

Question 7

How are Sperry and Casey different in their Sample?

Answer 7

Sperry’s study used 11 split brain patients. This is a small sample as a commissurotomy is a relatively rare procedure. On the other hand, Casey’s original sample consisted of 562 4-year-olds. Therefore, Casey’s sample is much larger and therefore more likely to be representative and generalisable.

Question 8

To what extent does the contemporary study change our understanding of the key theme of regions of the brain?

Answer 8

Casey adds to Sperry’s research by providing insight into the role of other regions of the brain and how they effect behaviour, such as the inferior frontal gyrus and the ventral striatum. Sperry’s study showed that certain areas of the brain had certain functions but Casey’s research shows which parts of the brain are involved in delaying gratification.

Question 9

How does regions of the brain link to cultural diversity?

Answer 9

Both of the studies focussed on American participants so both studies are limited in their
ability to explain cultural differences.

Question 10

How does regions of the brain link to social diversity?

Answer 10

It doesn’t!

Question 11

How does regions of the brain link to individual diversity?

Answer 11

Sperry suggested that individual differences in the brain lead to observed differences in behaviour and Casey et al furthered this understanding by focusing on more specific regions of the brain such as VS and IFG that contribute to individual differences like ability to delay gratification.

Question 12

How are Blakemore & Cooper and Maguire different in their research methods?

Answer 12

Blakemore and Cooper is a laboratory experiment as it was carried out in a lab and the researchers manipulated the IV of rearing the kittens in either a vertical or horizontal visual environment. However, Maguire was a quasi experiment as the IV of whether each participant was a London taxi driver or not was not manipulated by the experimenters.

Question 13

How are Blakemore & Cooper and Maguire different in their ethics?

Answer 13

Blakemore and Cooper’s study involved visual deprivation of kittens, and therefore is unethical as it can be argued to have caused the kittens physical and psychological harm as it hindered their visual development. However, the researcher claimed that the visual deprivation did not seem to distress the kittens. Maguire’s study was ethical as they gain informed consent from participants.

Question 14

How are Blakemore & Cooper and Maguire similar in their practical applications?

Answer 14

Both studies provide evidence for neuroplasticity and how experiences shape brain structure and function. Blakemore & Cooper demonstrated how early visual experiences affect neural development in the visual cortex, while Maguire showed how environmental demands lead to changes in the hippocampus. This has practical applications in rehabilitation and education. However, Blakemore and Cooper’s findings may not be generalisable to humans as the study was carried out on cats, and Maguire’s findings may not be generalisable to the general population who are not London taxi drivers.

Question 15

How are Blakemore & Cooper and Maguire different in their data collected?

Answer 15

Blakemore & Cooper collected both qualitative and quantitative data. They recorded behavioral observations (e.g. how the kittens responded to visual stimuli) as well as neurophysiological data (e.g. the orientation selectivity of neurons in the visual cortex). However, Maguire only collected quantitative data through analysing MRI scans of participants’ brain using VBM (Voxel-based Morphometry) and pixel counting.

Question 16

How are Blakemore & Cooper and Maguire different in their sample?

Answer 16

Blakemore and Cooper’s sample consisted of cats (2 were used to study the neurophysiological effects). On the other hand, Maguire’s study consisted of 16 right-handed male London taxi drivers. Blakemore and Cooper’s findings may not be generalisable to humans as the study was carried out on cats, and Maguire’s findings may not be generalisable to the general population who are not London taxi drivers.

Question 17

To what extent does the contemporary study change our understanding of the key theme of Brain Plasticity?

Answer 17

Blakemore and Cooper’s study proved neuroplasticity as the kittens’ early visual experience affected their behaviour and neurophysiology. Maguire showed that neuroplasticity was present in humans too, as they showed that being a London taxi driver and therefore using more spatial memory skills increases hippocampal volume and grey matter in the hippocampi, showing that experiences can affect brain structure.

Question 18

How does Brain Plasticity link to individual diversity?

Answer 18

Maguire et al’s research showed that brain plasticity does not only apply to animals such as cats but to humans as well. Maguire et al showed that use of
navigation skills and spatial memory led to grey matter in the posterior hippocampi to develop to
accommodate this demand.

Question 19

How does Brain Plasticity link to social diversity?

Answer 19

Brain plasticity occurs in humans as well as cats.

Question 20

How does Brain Plasticity link to cultural diversity?

Answer 20

It doesn’t!

Question 21

What is the background of Sperry?

Answer 21

Lateralisation of function refers to the idea that two halves of the brain are functionally different and that each hemisphere has functional specialisations. Sperry believed that studies involving split-brain patients reveal the ‘true’ nature of the two hemispheres because a commissurotomy which
deconnects the two hemispheres means they can only work independently.

Question 22

What is the aim of Sperry?

Answer 22

To investigate the information processing of split-brain patients who had had their corpus callosum cut, in order to investigate the lateralisation of function between the 2 hemispheres of the brain.

Question 23

What is the method of Sperry?

Answer 23

This is a quasi experiment because the IV (having a split brain or not) was not directly
manipulated by the researchers. Participants with split-brains had already undergone the commissurotomy to reduce severe epilepsy. No
actual control group was necessary for comparison in the study because the functions and abilities of the visual fields and hemispheres in non
split-brain individuals was already known. The dependent variable (DV) was the participant’s ability to perform a variety of visual and tactile tests.
It could be considered a collection of case studies as extensive tests were carried out on a very small sample (11 split-brain patients in total).

Question 24

What is the sample of Sperry?

Answer 24

11 split-brain patients who had undergone a commissurotomy (surgery in which the corpus collosum is severed)

Question 25

What is the procedure of Sperry?

Answer 25

Visual Task: The participants would have one eye covered and were told to focus on the point in the middle of the tachistoscope. Information presented to the left of the focal point would be seen in the left visual field which would then by processed in the right hemisphere and vice versa. Wearing an eye patch and staring at the focal point were controls. These controls ensure that stimuli was presented only to the desired visual field. All visual stimuli was presented for only 0.1 seconds. This was another control as it is too quick for eye movements to cause visual information to enter both visual fields. Tactile Task: Participants were introduced to objects by an experimenter, who placed them in the participants’ hands. Objects placed in the right hand of the participant are processed in the left hemisphere. Objects placed in the left hand of the participant are processed in the right hemisphere.

Question 26

What is the findings of Sperry?

Answer 26

* Participants would only recognise stimuli if the stimuli was presented again to the same visual field. * Information presented to the right visual field (left hemisphere) could be described in speech and writing (with the right hand). * Information presented to the left visual field (right hemisphere) could not be described in speech and writing participant could point with their left hand to a matching picture presented among a collection of pictures. $/? task findings. * If different figures were presented simultaneously to different visual field, for example ‘$’ sign to the left visual field and ‘?’ to the right visual field, the participant could draw the ‘$’ sign with his left hand but reported that he had seen a ‘?’. * Objects felt by one hand were only recognised again by the same hand * When two objects were placed simultaneously in each hand and then hidden in a pile of objects, both hands selected their own object and ignored the other hand’s object.

Question 27

What is the conclusion of Sperry?

Answer 27

Lateralisation of function exists as people with split-brains have 2 hemispheres that do not communicate. The left hemisphere controls language and speech, and the right controls perception and creativity.

Question 28

What is the background of Casey?

Answer 28

Delay of gratification refers to the ability to give up an immediate reward for a better, but delayed reward. A low delayer is someone who is not able to delay gratification, whereas a high delayer is someone who is able to delay gratifcation.

Question 29

What is the aim of Casey?

Answer 29

To investigate whether delay of gratification in children predicts impulse control abilities and sensitivity to alluring or social cues in adulthood.

Question 30

What is the method of Casey?

Answer 30

The study was longitudinal as it was conducted over a many years with the same participants. It was also a quasi-experiment as the participants naturally fell into either high-delaying or low-delaying groups and this could not have been manipulated by the experimenter. The study also used a correlation to consider the relationship of brain areas and behaviours during delay of gratification.

Question 31

What is the sample of Casey?

Answer 31

562, 4-year-olds from Stanford’s Bing Nursery School. 155 of the original 562 were studied in their 20s (1993). 135 of the original 562 were studied in their 30s (2003).

Question 32

What is the procedure of Casey?

Answer 32

Procedure 1: * Participants completed two versions of the go/no-go task. The “cool” version of the task consisted of male and female stimuli which were presented, one sex as a “go” stimulus to which participants were instructed to press a button, and the other sex as a “no-go” stimulus to which participants were instructed to withhold a button press. * Before the onset of each run, a screen appeared indicating which stimulus category served as the target. * Participants were instructed to respond as quickly and accurately as possible. * The “hot” version of the go/no-go task was identical to the “cool” version except that facial expressions served as stimuli. * The tasks were presented using programmed laptop computers sent to participants’ homes. * In Experiment 2, fMRI scanners were used to investigate brain activity in certain brain regions. It was expected that low delayers would have decreased activity in the right prefrontal cortex and increased activity in the ventral striatum compared to high delayers.

Question 33

What is the findings of Casey?

Answer 33

* There was no difference between the high and low delayers in their response to the cold task * In the hot task, low delayers made more false alarms than high delayers. * High delayers had higher activity in the Inferior Frontal Gyrus and lower activity in the Ventral Striatum, and low delayers had lower activity in the Inferior Frontal Gyrus and higher activity in the Ventral Striatum

Question 34

What is the conclusion of Casey?

Answer 34

Individuals who are low delayers during childhood will find it more difficult to resist temptation in adulthood. Also, there are differences in brain activity between high and low delayers.

Question 35

What is the background of Blakemore & Cooper?

Answer 35

The background of Blakemore and Cooper’s study is based on the idea that brain development, particularly visual development, is influenced by environmental factors as well as biology. Previous research showed that the brains of newborn kittens have plasticity, meaning their neurons can change in response to visual experiences. Specifically, it was known that the visual cortex has orientation-selective neurons, which respond to lines at specific angles.

Question 36

What is the aim of Blakemore & Cooper?

Answer 36

To investigate the physiological and behavioural effects of a limited visual experience and whether brain development/plasticity occurs due to experiences rather than nature.

Question 37

What is the method of Blakemore & Cooper?

Answer 37

This was a laboratory experiment which used an independent measures design. The independent variable (IV) was: whether the kittens were reared in a horizontal or a vertical environment. The dependent variable (DV) was their visuomotor behaviour once they were placed in an illuminated environment i.e. whether the horizontally raised kittens could detect vertically aligned objects and/or if the vertically raised kittens could detect horizontally aligned objects.

Question 38

What is the sample of Blakemore & Cooper?

Answer 38

Kittens (studied from birth) were randomly allocated to one of the two conditions. Two of the kittens (one reared in a horizontal and one in a vertical environment) were used to study neurophysical effects.

Question 39

What is the procedure of Blakemore & Cooper?

Answer 39

* The kittens were reared from birth in a completely dark room. * From the age of 2 weeks until age 5 months, for 5 hours a day, they were put into a tall cylinder. The entire inner surface was covered with black-and-white stripes, either vertical or horizontal. There were no corners to its environment and no edges to its floor. It could not see its body as it wore a wide black collar that restricted its visual field. * The kittens did not seem upset by the monotony of their surroundings and sat for long periods inspecting the walls of the tube. * The kittens were then taken for several hours each week from their dark cage to a small, well-lit room, furnished with tables and chairs. * Their visual reactions and behaviours were observed and recorded. * At 7.5 months, two of the kittens (one reared in the horizontal and one reared in the vertical environment) were anaesthetised so their neurophysiology could be examined.

Question 40

What is the findings of Blakemore & Cooper?

Answer 40

* All of the kittens were severely visually impaired. They showed no visual placing when brought up to a table top and no startle response when an object was thrust towards them. They guided themselves mainly by touch. * Kittens raised in the horizontal environment could not detect vertically aligned objects and vice versa * Only the eyes of the kitten brought up in vertical stripes followed a rod held vertically and only the eyes of the kitten reared in horizontal stripes followed the rod if it was held horizontally * Horizontal plane recognition cells did not‘fire-off’ in the kitten from the vertical environment and vertical plane cells did not‘fire-off’ in the kitten from the horizontal environment.

Question 41

What is the conclusion of Blakemore & Cooper?

Answer 41

* Visual experiences in the early life of kittens can modify their brains and have profound perceptual consequences. * Brain development is determined by the functional demands made upon it, rather than pre-programmed genetic factors. * It is questionable as to whether results can be generalised to humans.

Question 42

What is the background of Maguire?

Answer 42

Brain plasticity refers to the brains ability to change its structure and function. Maguire wanted to test brain plasticity by seeing if peoples job can affect their brain structure.

Question 43

What is the aim of Maguire?

Answer 43

Maguire aimed to prove brain plasticity and to show that the hippocampus in the human brain is the structure associated with spatial memory and navigation.

Question 44

What is the method of Maguire?

Answer 44

This was a quasi experiment because the IV – whether the participant was a London taxi driver or not - was naturally occurring and so could not be manipulated or controlled by the researchers. The DV was the volume of the hippocampi including their anterior, body and posterior regions; measured by analysing MRI scans of participants’ brain using VBM (Voxel-based Morphometry) and pixel counting.

Question 45

What is the sample of Maguire?

Answer 45

The experimental group of 16 taxi drivers were all healthy, right-handed, male London taxi drivers, mean age 44 years (range 32-62 years), mean time as a licensed London taxi driver (passed The Knowledge) 14.3 years (range 1.5-42 years). This was then compared to pre-existing scans of 50 healthy, right-handed males (control group).

Question 46

What is the procedure of Maguire?

Answer 46

The MRI scans of all participants were analysed using: * VBM (voxel-based morphometry) which is an automatic procedure that normalises the scans to a template to eliminate overall brain size as a variable and then identifies differences in grey matter density in different regions of the brain. * Pixel counting of the volume of anterior, body and posterior cross-sections of the taxi drivers and controls ’hippocampi. The images were analysed by one person experienced in the technique and blinded to whether the scan was of a taxi driver or a control and the VBM findings.

Question 47

What is the findings of Maguire?

Answer 47

VPM * Taxi drivers had significantly increased grey matter volume in the right and left posterior hippocampi compared to controls. * In the controls there was a relatively greater grey matter volume in the right and left anterior hippocampi compared to taxi drivers Pixel counting * Taxi drivers had a significantly greater posterior hippocampal volume than controls. * Controls had a significantly greater anterior right hippocampal volume than the taxi drivers. * Correlations showed a significant positive correlation between the length of time as a taxi driver and the right posterior hippocampal volume, but a negative correlation for the anterior hippocampal volume.

Question 48

What is the conclusion of Maguire?

Answer 48

* There are regionally specific structural differences between the hippocampi of licensed London taxi drivers compared to those who do not drive London taxis. * The professional dependence on navigational skills in licensed London taxi drivers is associated with a relative redistribution of grey matter in the hippocampus. * Findings show plasticity in brain structure

Question 49

How does Sperry's study link to it's key theme?

Answer 49

Links to regions of the brain as Sperry investigated the effects of hemisphere disconnection on different tasks allowing them to understand the functions of the right and left hemisphere of the brain. They found that the left hemisphere controls language and speech, and the right controls perception and creativity, showing that different regions of the brain have different functions (lateralisation of function)

Question 50

How does Casey's study link to it's key theme?

Answer 50

Links to regions of the brain as it linked delay gratification to the inferior frontal gyrus, ventral striatum and prefrontal cortex using fMRI scans during go/no go tasks. Low delayers were found to have decrease activity in their right inferior gyrus and increased activity in their ventral stratum. Therefore, different regions of the brain have different functions.

Question 51

How does Blakemore & Cooper's study link to it's key theme?

Answer 51

Links to brain plasticity as looked at how brains of kittens can change depending on their early visual experiences. Kittens were raised in dark for 2 weeks and placed in horizontal or vertical visual apparatus for 5 hours a day till they were 5 months old. When taken into a well lit room the kittens showed ‘behavioural blindness’, proving plasticity of the brain.

Question 52

How does Maguire's study link to it's key theme?

Answer 52

Links to brain plasticity as they looked at how humans brains can adapt for humans who rely on navigational skills. The hippocampus is a region of the brain which is associated with spacial awareness and navigation. They found that taxi drivers had greater grey matter volume in their right and left posterior hippocampus compared to control group. Found via Pixel counting that taxi drivers had a greater posterior hippocampus volume. This suggests that human brains have plasticity.

Question 53

How does Sperry's study link to the Biological Area?

Answer 53

Biological because it is showing, through split-brain patients, the way in which different skills are localised within the two hemispheres of the brain and distinct areas control specific behaviours.

Question 54

How does Casey's study link to the Biological Area?

Answer 54

Biological because it involves trying to investigate whether there is any differences in brain structure between high and low delayers. This is done through fMRI scans.

Question 55

How does Blakemore & Cooper's study link to the Biological Area?

Answer 55

Biological because it focuses on neurons, and also because it investigates whether experiences can affect biology.

Question 56

How does Maguire's study link to the Biological Area?

Answer 56

Biological as it focusses on brain structure. They investigated whether being a taxi driver in London increased hippocampal volume and grey matter. Therefore, it investigates whether experiences and lifestyle can affect biology.