Post a 200- to 300-word response to the following: Many studies have been conducted on cerebral lateralization revealing different functionalities of the left and right hemispheres. Describe four methods for studying cerebral lateralization.
The first way to study brain lateralization is through brain damage, specifically damage to the cerebral commissures (Pinel, 2007). The corpus callosum, in particular, is a part of the cerebral commissures that connects the left and right cerebral hemispheres. If this link between the two cerebral hemispheres is broken, then each side of the brain operates independently in many respects. Also, aphasia is produced by damage to the inferior prefrontal cortex which can cause problems with language comprehension and production. Lastly, apraxia is almost always caused by left-hemisphere damage and includes an inability to perform movements outside of context.
Sodium Amytal Test
This way of studying brain lateralization involves the injection of sodium amytal into a vein either going into the left or right side of the brain. When injected into the correct vein this substance anesthetizes either one side of the brain or the other, allowing researchers to study the function of one side of the brain at a time. While each side of the brain is drugged researchers administer tests that deal with well-known series and are asked to give names to common pictures.
Dichotic Listening Test
This test is much less invasive and involves auditory recognition of two simultaneous numbers spoken into each ear. In this way, researchers can ascertain which side of the brain predominantly has access to the cortical auditory centers.
Functional Brain Imaging (fMRI) and Positron Emission Tomography (PET)
In this type of test, both fMRI and PET brain scans are used to monitor cerebral activity during common tasks such as reading. In this way, a typical predisposition for left hemisphere dominance in the area of language has been discovered.
Hemispheres of the Brain
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.
|Left Hemisphere||Right Hemisphere|
| Words (Pinel, 2007)|
Finding Meaning in Memories
Movement in Spatial Patterns
Perceptual Aspects of Memories
Mental Rotation of Shapes
Pinel, J. P. J. (2007). Basics of biopsychology. Boston, MA: Allyn and Bacon.