ABSTRACT
This chapter discusses the factors responsible for hand-edness asymmetries at a later point. The major theories of handedness asymmetries are reviewed. Obviously, genetic factors contribute to dextral dominance in the human species, and perhaps even indirectly exert their influence over the environment so that it can capitalize on this right-sided predisposition. The eventual result is that natural right-handed dominance is weakened as left-handed preferences develop in reaction to the trauma, and effectively summarized this position by stating that it is not left-handedness per se that is determined genetically. The reason ipsilateral cortex generated more blood flow activity instead of the contralateral side has been the focus of discussion among researchers. It might be that any gender differences noted in cortical organization can be attributed partially to the hand dominance of the subject tested. Some of the pathological factors that predispose some sinistrals to particular abnormalities and certain neuropsychological disorders are discussed next.
