Research support for lateralisation in connected brain
Fink et al. - PET scans
When participants were asked to attend to global elements of an image (a whole forest) regions of the right hemisphere were more active
When asked to focus on finer details (a single tree) the left hemisphere dominated
Therefore, visual processing is the same of hemispheric lateralisation in connected and split-brain participants
Research support for hemispheric lateralisation
Case study of EB
Left hemispherectomy due to a tumor
Initially, he experienced significant language impairments
Therefore, shows role of left hemisphere in language
Counterpoint to EB
Over time, his right hemisphereadapted to take over these functions
Therefore, the case of EB also shows that the brain can recognise itself, suggesting a level of flexibility in lateralisation
Controlled conditions
Sperry’s split-brain research has a high level of control and standardisation, ensuring reliability
Sperry used specialised equipment, (tachistoscope), to control the presentation of visual stimuli to one hemisphere at a time, ensuring the images were shown exclusively to one visual field for a fraction of a second, preventing communication between the hemispheres
