Correlates of the dichotic right-ear effect.

A total of 302 subjects were tested on a verbal dichotic listening task and a variety of measures related to lateralization, including familial sinistrality, sighting eye dominance, handwriting position, and arm folding behavior. The majority of these subjects were more accurate on the right ear in the dichotic testing, and this right-ear advantage (REA) was correlated with handedness. handwriting position, arm folding, and familial sinistrality (FS), considered in isolation, were not able to improve the prediction of the REA. There was, however, a significant effect of sighting eye, and in interaction between handedness, sighting eye and FS. Left-eyes subjects, regardless of handedness, showed weaker REAs than right-eyed subjects. This effect was most obvious in FS--right-handers and in FS+ left-handers. These data suggest that knowledge of sighting eye dominance may assist in the prediction of cerebral lateralization of language functions.