Biological area: Sperry Flashcards
The language abilities of the left hemisphere were first identified by who and when?
19th Century by Broca and Wernicke
What was Wernicke’s area responsible for?
Speech comprehension
What was Broca’s area responsible for?
Speech production
What was the aim of Sperry’s study?
To investigate the effects of the disconnection between the hemispheres and show the different functions of the hemispheres
What was Sperry’s aim in terms of the lateralisation of brain function?
To map lateralisation of brain function and show that information in one side of the brain was not accessible to the other side
What was Sperry’s research method?
Quasi experiment and self report
What evidence is there from the study that the research method was quasi?
The main IV was whether or not the P’s had a split brain which was already existing
Describe the sample used in Sperry’s study
11 patients who had commisurotomy as a result of severe epilepsy
What are 2 weaknesses of Sperry’s sample?
Small sample size
May not have ‘normal’ brain as they all had severe epilepsy
Why did Sperry use the sample that he did?
Because the corpus callosum had been cut so therefore the hemispheres were not able to communicate
When objects were presented to the right visual field, what hemisphere of the brain did this information go to?
Left
What could the P’s do with information presented to the right visual field?
They could say what they had seen
When objects were presented to the left visual field, what hemisphere of the brain did this information go to?
Right
What could P’s do with objects presented to the left visual field?
They could draw/pick up what they had seen
When visual stimuli were presented simultaneously to different visual fields (e.g. an image of an apple to the left and an image of a key to the right), which hemisphere did the apple and key go to?
Apple would go to the right
Key would go to the left
What could the participants do when presented the apple and key to the different visual fields?
They could draw the apple and then could say that they had seen the key
What couldn’t the participants do when they were presented the apple and key to the different visual fields?
They couldn’t say that they had seen the apple and were unsure why they drew the apple
When simple mathematical problems were presented to the left visual field, which hemisphere did this go to?
Right
What could the participants not do when they were presented with maths to the left visual fired?
They couldn’t answer the mathematical problem
When a nude pin-up was presented to the left visual field, which hemisphere did this go to?
Right
What did the participants do when the nude pin-up was presented to the left visual field?
They blushed
What could participants not do when the nude pin-up was presented to the left visual field?
They couldn’t say what they saw
When objects were felt with the right hand only, what hemisphere did this information go to?
Left
What could participants do when they felt an object with their right hand?
Identify the object by speech and in writing
When objects were felt with the left hand only, what hemisphere did this information go to?
Right
What could participants do when they felt an object with their left hand?
They could find it with their left hand
What could the participants not do when they had felt an object with their left hand?
They couldn’t identify the object and seemed to make wild guesses
Which ethical guidelines did Sperry uphold?
Consent, Confidentiality and Deception
Why could it be argued that Sperry broke protection from harm?
Because some mild frustration may have been caused from the activities
Was the procedure standardised and replicable? (Internal reliability)
Yes - number of controls (e.g. in silence, 1/10 of a second)
Was the sample large enough to suggest a consistent effect? (external reliability)
Limited but such patients aren’t easily available
Was the research testing the effects of deconnected hemispheres or could there be any other possible reasons for the reported behaviour? (internal validity)
Unlikely that patients deliberately gave the wrong answers however as a result of them having severe epilepsy their hemispheres may be atypical
Were the visual true to life?
No
Were the tactile tasks true to life?
Yes, possibly similar to trying to finding an object in a bag with only one hand
