Handedness and laterality of the viscera

Abstract

The biological basis of handedness remains to be determined in humans. Hepper et al.1 supported the genetic explanation of handedness by demonstrating a preference for thumb sucking before birth. However, Dryden2 rejected this hypothesis and proposed that handedness was related to neuromuscular development secondary to the oxygen level in the blood. We have now confirmed the independence of handedness and the asymmetric position of the viscera in humans. …