By 19th century, from the studies of people with brain injury, that the different areas of brain are responsible for performing different kind of tasks. For example, the “language center” resided in the left hemisphere of the brain. The people with brain injuries who were found to have lesions in certain areas of brain lost their faculty of speech.
But, Doctor Roger Sperry, was confirm and demarcate different area functions of the brain in left and right hemisphere. He arrived at this conclusion based on experiments on split brain people. People suffering from epilepsy in 1960 have no cure except to disconnect the two hemispheres by removing corpus callosum which connects the two hemispheres.
This led the patients to live normal life after operation, but somewhat odd behavior was observed in these patients. After such operation, each part of brain learn individually but is unaware of what is going on in the other part. Thanks to modern advances in science, now a small portion of corpus callosum is removed to keep the two hemispheres in communication with each other.
These studies indicated that each hemisphere performs specialized tasks. List of some tasks performed by these parts is given below:
- It is normally specialized in taking care of the analytical and verbal tasks.
- The left side speaks much better than the right side,
- Right half takes care of the space perception tasks and music, for example.
- The right hemisphere is involved when you are making a map or giving directions on how to get to your home from the bus station.
- The right hemisphere can only produce rudimentary words and phrases, but contributes emotional context to language.
- Without the help from the right hemisphere, you would be able to read the word “pig” for instance, but you wouldn’t be able to imagine what it is.
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