Is handedness related to anxiety? New answers to an old question.

Is handedness related to anxiety? Two separable dimensions of handedness have been considered in previous studies: Direction of the preferred hand (left or right) and the consistency with which the preferred hand is used over the nonpreferred hand (consistent or inconsistent). Findings have included (1) left-handedness being associated with greater anxiety than right-handedness, (2) consistent-handedness being associated with greater anxiety than inconsistent-handedness and (3) neither dimension being associated with anxiety. Here, we administered measures of trait anxiety, state anxiety and worry to individuals classified as consistent-left, inconsistent-left, inconsistent-right or consistent-right. Neither direction nor consistency had a main effect on any measure. However, there was a direction by consistency interaction in trait and state anxiety measured on the State/Trait Anxiety Inventory. Among right-handers, inconsistent individuals reported less anxiety than consistent individuals. Among left-handers, consistency was unrelated to anxiety. In consequence of this pattern, inconsistent right-handers were less anxious than inconsistent left-handers. Hence, supporting prior studies, left-handedness was associated with greater anxiety than right-handedness (but only among inconsistent individuals) and consistency was associated with greater anxiety than inconsistency (but only among right-handers). These findings advance our understanding of handedness consistency as an important individual difference factor in personality and cognition.