Sperry gh

Sperry 

Aim: Test functioning of seperated and independent hemispheres

Participants 

• Oppurtunity sample
• 11 Participants 
• Undergone corpus callostomy (severe the corpus callosum) to contorl epilsepsy 

Method 

• Lab experiment 
• Vision divided into left and right visual field, hands are screened from view, with one eye covered they gaze at centre of screan and stimuli flashed for 1/10th of a second 
• Tactile Tasks: objects placed in one of subjects hands, thus sensory information percieved by only one hemisphere. Subject then has to find object with same or opposite hand

Results 

• Information percieved by one hemisphere only recognised by same hemisphere

• Visual material seen by left hemisphere can be described in speach and writting. Same information shown to right hemisphere then the subject insists they did not see anything but can identify object non verbally

• Different figure shown to each visual field then: will draw image from left hemisphere but name object from right 

Results II 

• Object placed in right hand = easily names + described but object placed in left hand = wild guesses or no awareness it is in their hand but they can still select it from a list 

• Two objects, one in each hand = each hand will search independently for its own object, other object rejected by other hand.

Conclusions 

• Findings confirm patients with severed corpus callosum have "two minds in one body"

Evaluation 

Strength

• Quasi = can investiaget variables that are not able to be investigated in strict laboratory 

Weaknesses 

• Quasi = Does not give researcher full control over IV 
• Little ecological validity / mundane realism 
• Small sample

Uses

• Helping people cope with the effects of brain damage