Lateralisation of function and split brain studies Flashcards
Hemespheric laterialisation
The idea that each hemisphere of the brain is specialised to perform a specific function
Corpus collosum
Bundle of fibres which connects the two hemispheres allowing them to communicate
Left hemisphere
-Controls language functions-speech production and comprehension
Right hemisphere
-Controls emotional recognition, spatial awareness and pattern recognition
Contralateral
Each hemisphere controls the opposite side of the body.
How can split brain research tell us about the specific functions of each hemisphere
-We can present individual to one hemisphere of the brain and see how it functions seperately as the corpus collosum is cut so each hemisphere cannot communicate to the other
Sperry split brain research.
-Studied split brain patients, presented information to one of their brain hemispheres by covering one eye so the information only goes to one visual feild and is only processed by one hemisphere,
Sperrys research
-Got split brain patients, presented them with words to their individual visual fields by getting them to cover one eye and then presenting information to the
-left visual field to be processed by the right hemisphere of the brain
and the right visual field processed by the left hemisphere of the brain
He found that information presented to the left visual field was able to be written but not spoken, whereas information presented to the right visual field was able to be spoken but not written, this suggests that each hemisphere plays a specific, specialised function, the left hemisphere controls language functions and cannot perform spatial/motor functions and the right hemisphere controls spatial and motor functions and cannot perform speech functions-each side plays a specific function
What did sperry find
When information is presented to the left visual field and processed by the right hemisphere, they could draw the world but not say it out loud-right hemisphere controls visual/spatial and motor functions and doesn’t perform speech functions
-When information is presented to the right visual field processed by the left hemisphere, they could say the word but could not write or draw it showing the left hemisphere controls language functions and doesn’t perform spatial/motor functions.
Limitation
Patients may have pre existing neurological damage due to epilepsy, the surgery itself and long term medication use, may have inhibited functioning due to damage-cannot be generalised to the wider population without impaired brain function or show they have lateralisation of function.