biopsychology- lateralisation of function

Question 1

what is hemispheric lateralisation?

Answer 1

the view that functions are performed by distinct regions of the brain and the left hemisphere is different to the right hemisphere

Question 2

what connects the brains hemispheres ?

Answer 2

corpus collosum

Question 3

what is the left side of the brain associated with ?

Answer 3

language functions (Boca’s and Wernicke’s area)

Question 4

what is the right side of the brain associated with ?

Answer 4

spatial functions

Question 5

who conducted split brain research ?

Answer 5

Sperry

Question 6

who was sperrys split research on ?

Answer 6

sample of 11 people who had undergone a commissurotomy, which involves cutting the corpus callosum and other tissues to separate communication between the two hemispheres and control seizures.

Question 7

what was the procedure Sperry did for split brain research?

Answer 7

project words or images onto a screen in the right and left fields of vision whilst one eye is covered, to test for whether the patients would be able to say the word or describe the image

Question 8

what were findings of Sperry’s research ?

Answer 8

patients were able to say words in the right visual field since that links to the left hemisphere which is associated with language but couldn’t say words in left visual field but could draw the word since they had spacial awarness.

Question 9

according to Sperry’s research, what would happen if a participant tried to draw an object presented in right visual field?

Answer 9

they wouldn’t be able to draw it since information would go to LVF which is associated with language.

Question 10

when was sperrys research?

Answer 10

1968

Question 11

what were the different conditions in sperrys research?

Answer 11

describing what you see
recognition by touch
composite words
matching faces

Question 12

describe the findings of the ‘describing what you see’ condition of sperrys research

Answer 12

if a pp was shown an image to the right visual field they could easily describe it, but it was shown to the left visual field they typically reported that nothing was there. This is because information cannot be transferred from one hemisphere to the other.

Question 13

describe the findings of the ‘recognition by touch’ condition of sperrys research

Answer 13

although pp could not verbally describe images/words presented to the left visual field they could select the object out of a grab bag. (objects were behind a screen and unseen)

Question 14

describe the findings of the ‘composite words’ condition of sperrys research

Answer 14

if a words were simultaneously presented to each visual field (such as key and ring) the PP would select a key with their left hand and say the word ring.

Question 15

describe the findings of the ‘matching faces’ condition of sperrys research

Answer 15

• the right hemisphere was dominant in matching faces
• when asked to match faces
• the pictures processed by the right hemisphere were selected but those by the left H were ignored
• however left could verbally describe face

Question 16

evaluate sperrys spilt brain research!!

Answer 16

+ standardised and controlled - participants only saw words on screen for 1/10th of a second this means that it is likely it was testing only one hemisphere more valid
- however small sample - cause and effect of commisurtomoy cannot be generalised
+ research support from rogers - chickens do two tasks at once suggesting brain can operate its functions at once because theyre diferent and lateralised
- plasticity - functions arent just associzted wth one side - homologous area adaptation

Question 17

explain how sperrys research was standardised

Answer 17

PP asked to stare at a fixation point, image flashed for one tenth of a second, disabling them from looking at it with both eyes meaning infomation went to both hemispheres. This means more controlled and valid. We can be sure it was measuring hemispheric lateralisation.

Question 18

why does sperry have a theoretical basis?

Answer 18

he paved the way for more research to be conducted, very useful, pucetti even argued we have two brains

Question 19

explain hemispheric lateralisation

Answer 19

brain is divided into two sides, right and left hemisphere.
some of our psychological traits are dominated by either side.
for example, sperry believed the left side of the brain is associated with language functions and the right side of the brain is linked to spatial fuctions.
generally activity on the left side of the body is controlled by the right side of the brain and vice versa
the outer layer of the brain = cerebral cortex/grey matter

Question 20

what affect does a commissurotomy have on neural communication?

Answer 20

it removes communication network between each side of the brain

Question 21

what is the aim of split-brain research?

Answer 21

to investigate weather neural processes organised in way that each hemisphere of the brain has a different function

Question 22

what surgery had sperrys sample had?

Answer 22

commisurotimy

Question 23

how long did the PP look at fixation point?

Answer 23

1/10th of a second

Question 24

how would a normal brain deal with sperrys research and why does this mean that we can asses one hemisphere of sperrys sample?

Answer 24

the corpus collosum would immedietly share the infomation between the hemispheres giving a complete picture of their visual fields. But because in the sample this infomation cannot be shared across the hemispheres it is truly assesing the function of either left/roght hemisphere.