Abstract

Cerebral lateralization is defined as the morphological and functional differences between two brain hemispheres. Hand preference is accepted as a functional cerebral latera lization. In most of the people, Wernicke's (posterior speech cortex) and Broca's areas (posterior speech cortex) are better developed in one hemisphere compared to the other. The better developed hemisphere is called as dominant hemisphere. The left hemisphere is the dominant one in 95% of the people. Hand preference is described as using the right or left hand for skilled activities such as writing, painting and using fork-knife tools. Hand preference is thought to be afected from the factors such as gender, genetics and intra uterine position. The significant relationship between hand preference and immune system or neuropsychiatric disorders was reported in many studies. Further studies on this subject can explain the physiopathology of a number of neuroen dcrine, neuroimmune and psychiatric disorders and, therefore, their treatment approaches will also be chanced.