Cerebral lateralization as a source of interindividual differences in behavior.

Cerebral laterality can no longer be considered an exclusively human trait, as over the last 15 years there has been an emergence of data to suggest that animal brains are also lateralized. Morphologic, chemical and behavioral indices of brain asymmetry in the rodent have been reported, and it is suggested that variations in the magnitude and direction of these indices are determined by a complex interaction of genetic, hormonal and experiential factors. Interindividual differences in cerebral laterality have been shown to covary with, or predict, individual differences in spatial behavior and stress reactivity, as well as susceptibility to stress pathology and drug sensitivity. Such findings suggest that it is possible to study individual differences in lateralized brain function through the use of animal models.