Handedness and language lateralization: Why are we right-handed and left-brained?


Around 90% of humans prefer their right hand for unimanual actions and are left-hemisphere dominant for language functions; a pattern far from negligible. The phenomena of handedness and cerebral lateralization for language are presented along with the different theories that attempt to explain the presence of these functional asymmetries. The focus is on the adaptive advantages both on the individual and the population level. Most importantly, the intriguing question of why humans are right-handed and left-brained and not the other way around is tackled; a number of evolutionary, cultural, and genetic accounts are presented, along with theories that explain the observed pattern of asymmetries by means of the different properties of the two cerebral hemispheres.

Hellenic Journal of Psychology