Split brain research

• Hemispheric lateralisation is when certain mental process and behaviours are controlled or dominated by one hemisphere rather than another.
• Sperry identifies which part of the brain has been affected. The corpus colosseum was cut in patients with Severe epilepsy allowing researchers to investigate the to which brain function is laterised
• 11 participants who had undergone split brain surgery due to epilepsy . Involving covering one eye and looking in a fixed point on a projection screen where pictures are projected to the right visual field or left visual field.
• Pictures shown to Right Visual Field could be described but not those to the Left Visual Field as there is no language centres in the left hemisphere.
• Recognition by touch was the next part experimented by Sperry. They could not describe the objects projected to Left Visual Field but able to select a matching object from a selection of a different objects using their left hand.
• The third finding was composite words. With there left hand, they would reach for or draw what they saw in there left visual field and they would say what they saw in the Right Visual Field.
• The fourth finding was matching faces. This is faces shown to the right visual field were consistently selected and the faces shown to the left visual field were consistently ignored. Composite faces are the half shown to the Right Visual Field could be described and the half shown to the Left Visual Field could be selected.
• A severed corpus callosum which means signals aren't sent all around the body.
• Broca area- Situated left frontal lobe. Responsible to speech production.
• Wernickes area- Left temporal lobe, thought to be involved in language process/ comprehension.
• The left brain is the analyser , viewing objects visible in right visual field , controls the right side of the body.
• The right side of the brain is the synthesiser( being creative). As well as this, viewing objects in left visual field. Controls left side of the body. As well as this, it is responsible for the emontial content in language. As well as this, it is responsible for music, spatial tasks, recognition and facial recognition.
• One strength of split brain research is pioneering work. This work has been very influential and very impactful on the market of today.
• Another strength of Sperry's split brain research is that there is real life application. This is because of the type of participants. They all have epilepsy which means that this can be useful for people with epilepsy to see where people have gone wrong.
• Another strength of Sperry's split brain research is that it is specialised. It also has controlled and standard procedures which are reliable and replicable which means it can be trusted very well for information.
• Another weakness of Sperry's split brain research is that it has a limited research sample as there was only 11 participants. This means that it is difficult to generalise to everyone as there is so limited peopel.
• Another limitation of split brain research is that it may not be ecologically valid. This is because the participants were in an artificial environment ( hospital) and their brains were cut open. So how do we know whether these results will occur outside of the lab?