Brain Lateralization
« Back to Glossary IndexBrain lateralization describes specialized functions of the hemispheres that are carried out at the same time on each side—increasing cognitive capacity. It develops naturally in children, who recover from brain damage better than adults. Left hemisphere is dominant for language (listening, reading, speaking, writing). Right, for visual motor tasks (judging position of objects in space and motor control of body’s left side). New research found healthy hemispheres compensate for damaged hemispheres by taking over functionsIt does this through neuroplasticity—the brain rewires itself into new neural connections to bypass the damaged region. Hemispheres are separated by the median longitudinal fissure but are interconnected by a thick band of nerve fibers (corpus callosum), allowing communication between healthy and damaged sides. Some specialized functions also overlap, enabling compensation. Lateralization can occur at different brain levels of the cortex, hippocampus, thalamus, cerebellum, andhypothalamus. Examples of hemisphere compensation:
- Language function: If left hemisphere is damaged, right hemisphere may take over some language functions—though less efficient.
- Motor control: Healthy hemisphere can partially compensate for motor function.
- Visual perception: Both hemispheres are responsible for visual processing, so healthy hemisphere can take over some visual tasks.
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