Sperry Flashcards
what is the background to sperrys study?
-previous research using split-brain animals showed numerous behavioural effects
-sperry set out this to show that each hemisphere: posses an independent stream of conscience awareness and has its own chain of separate chain of memory’s that are inaccessible to each other
what is the aim of sperrys study
to study the effects of a split brain in order to show that each hemisphere has a different function and therefore demonstrates lateralisation of functioning
what does the left hemisphere control and process?
-conrtols the right hand and right visual field
-processes language
what does the right hemisphere control and process?
-controls the left hand and left visual field
-processes pictures /symbols, and emotion
what is the sample to sperrys study?
11 split brain patients who had a history of advanced epilepsy which could not be controlled by medication
what was the method to sperrys study?
-Quasi Experiment as IV of having a split brain is naturally occurring
-procedure to treat epilepsy
-considered a case study as studies a small group of people, and testing them multiple times over a period of time longitudinally collecting qualitative data
-DV is the performance on the visual and tactile task as this demonstrates there lateralisation of functioning
what was the procedure?
-used a tachistoscope
-participants wore an eyepatch on one eye and sat in front of the screen with hand holds, and were asked to fixate on a black cross in the centre of the screen
-all images, words, and objects were of the same difficulty a to identify and were flashed 0.1 seconds
-standardised so it is replicable so results on lateralisation of functioning are more likely to be reliable
-allowed causality to be established between affect of split brain on lateralisation of functioning and therefore allowed a more valid explanation of functioning
describe the visual test
-images were flashed on a 35mm transparency from a projector for 0.1 seconds to either the left or right visual field while other eye was covered
-ppts were shown a symbol of a ? to there LVF and were asked if they could name it, if they couldn’t they were asked to draw it with their left hand
-ppts were shown a $ to their RVF and were asked the same questions if they could name it they were not asked to draw it.
describe the tactile test
-objects were placed in either left or right hand
-ppts were given a key in their left hand and asked to name it if they couldn’t they were given a grab bag and asked to select the item in their left hand amongst other items
-ppts were given a tennis ball in their right hand and were given a grab bag and told to locate the item in their hand.
what were the findings in sperrys study?
when ppts were shown a ? in their LVF they could not identify seeing it however they could draw it with their left hand, after seeing it they could name it
-when pots were shown a $ to their RVF they could easily name it as it was processed by the left hemisphere which controls language
what were the conclusions of sperrys study?
there is lateralisation of functioning, the left hemisphere is responsible for language and the left side of the body and the right hemisphere is responsible for the creative tasks and controls the left side of the body
- there is a lack of cross integration and the two hemispheres and they have there own stream of consciousness
What is lateralisation of functioning?
The two half’s of the brain are functionally different and that each hemisphere has functional specialisations
