Sperry Flashcards
What is epilepsy?
A condition brought on by abnormal electrical impulses discharging within the brain disrupting normal brain patterns
What is the surgery used to treat epilepsy?
Commissurotomy or Split brain surgery
How does a commissurotomy treat epilepsy?
The corpus callosum is cut so the abnormal electrical impulses could not spread throughout the brain
Why did Sperry choose to investigate people who had a commissurotomy?
He thought they were perfected for research into what each hemisphere of the brain actually dows
What is lateralisation of function?
One side of the brain has different role from the other
What is the corpus callosum?
Fibres that carry the majority of information between the two hemispheres of the brain
What is contralateral control?
The idea that each side of your body is controlled by the other side of your brain
What is a commissurotomy?
A surgical operation to sever the corpus callosum
What was Sperry’s aim?
To study the functions of separated and independent hemispheres
What was Sperry’s sample?
11 patients who had undergone a commissurotomy as a treatment for their epilepsy
They were compared with a group of people who had not undergone the surgery
How did Sperry collect his sample?
A surgery in America
What was a strength of the sample?
They were able to test the hemispheres independently as they were separated in the surgery
What were weaknesses of the sample?
Small sample size
2 people had the surgery 4-5 years ago so may have recovered
Perhaps the cause of results was epilepsy
What were the controls?
The symbols displayed
The images displayed
The objects used
The fixation point
1/10 second time for presentation
Hands being out of view
One eye being covered
Using a tachistoscope
What was the conclusion about the left hemisphere?
Has language ability (both written and verbal) and controls the right hand side of your body
What was the conclusion about the right hemisphere?
Can only communicate non-verbally and controls the left hand side of your body
Does this study have good informed consent?
Participants consented to participate following being approached through their hospital
Did the study have good confidentiality?
Details of each participant were kept confidential
Did the study protect participants from harm?
It may have been upsetting or embarrassing to not have full capabilities or understanding of your behaviour
Were participants deceived?
Participants were fully aware on the research
Was the study ethnocentric?
The sample was obtained from a hospital in America but the roles of each brain hemisphere should be universal so perhaps it doesn’t matter
How was the internal reliability of this study?
The procedure was very standardised and easy to replicate due to the amount of controls
Eg images were all shown for 1/10th of a second
How was the population validity of the study?
The sample was very specific (epileptic people who had split brain surgery) so it is not generalisable but it may not matter based on our natural biology
