Asymmetry

Synonyms

Hemispheric specialization

Definition

Asymmetry is the discordance between the right and left sides of the brain in respect to structure and/or function.

Current Knowledge

Although not initially linked to brain asymmetry, the first behavioral asymmetry that was likely noted was the superiority of motor skills exhibited by one hand, most commonly the right, over the other. The next real breakthrough with regard to asymmetry is generally thought to have occurred in the nineteenth century with the discovery that acquired language deficits (aphasia) were typically associated with lesions of the left hemisphere. Since then, other asymmetries, both functional and structural, have been identified with regard to the two cerebral hemispheres.

Structural Asymmetries

Structural asymmetries of the brain were first noted around the beginning of the twentieth century, but it was not until the late 1960s that these were first strongly correlated with functional differences between the...