Archive for March 7th, 2011

March 7, 2011

Lateralization

Brain lateralization [lat-er-uh-luh-zey-shuhn] is  the distribution of function into right and left hemispheres. In most brains the left hemisphere is the center of language, logic, and rationality and controls the right side of the body, and the right hemisphere is the focus of creativity, intuition, holistic thought, and controls the left side of the body. In common speech lateralization is referred to as handedness, the preference for using either the left or the right side of the body for certain things.

Lateralization occurs in animals when one side of the brain is stronger (more dominant) than the other. Until fairly recently it was  thought humans preferred the left or right sides of their body was because they could speak. However, it was later discovered that many nonverbal species display lateralization. For example, elephants often have preferences for whether they swing their trunks to the left or the right. Honeybees have right antennas that are more sensitive to smells. Parrots can be left- or right-footed, and some are ambidextrous. Chickens and minnows like to look for food with one eye and look out for predators with the other.