Our brain is divided into two main hemispheres, the left and the right. Each hemisphere is dominant in certain functions. Click either the left or the right hemisphere of the brain below and fill in the hemisphere’s appropriate functions.
The four methods for studying cerebral lateralization include the sodium amytal test, studying the effects of the brain lesions on both the left and right hemispheres, functional brain imaging, and the dichotic listening test.
The sodium amytal test involves injecting the sodium amytal into the carotid artery on either the left or right side of the neck which affects a corresponding hemisphere of the brain. The sodium amytal has an anesthetizing effect on the brain which allows researchers to study the language functionality of either or both hemispheres. The researchers will perform a series of tests on the patient while the brain is anesthetized. (Pinel, 2009)
Studying the effects of the brain lesions on both the left and right hemispheres is the earliest research done with cerebral lateralization. During this time, researchers were able to determine certain functionalities of the right and left hemispheres. Researchers thought the left hemisphere was dominant over the right side due to the studying of damaged left hemisphere and the amount of effect is had on different functions. (Pinel, 2009)
The least invasive procedure out of the four different methods is dichotic listening test where a patient will hear a number sequence at the same time in both ears. This number sequence though would be different for each ear which allows researchers to determine which the patience was more likely to recall. During this research, they found that patients would recall the number sequence from the right side versus the left side. (Pinel, 2009)
MRI or PET scans are called functional brain imaging which is monitored while a patient performs a certain task. During the research of the brain with MRI’s and PET scans, it was determined that the left hemisphere is dominant over the right when it comes to language functionality. (Pinel, 2009)
Reference: Pinel, J. P. J. (2009). Biopsychology. Boston, MA: Pearson ———————–
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