Home-Recorded Sleep Architecture as a Function of Handedness II: Consistent Right- Versus Consistent Left-Handers

Examination of individual differences in sleep architecture may help elucidate the mechanisms involved in sleep-related pathologies and cerebral processes involved in sleep. We (Propper et al., Brain Cogn. 2004;54:186–197) previously reported that degree or strength (i.e., inconsistent vs. consistent) of hand preference was more important than direction (i.e., left vs. right) of hand preference in examining sleep architecture-hand preference relationships. However, that study confounded direction and degree of hand preference; only 1 consistently left-handed individual was included in the consistently handed group. Here, we describe a comparison of the sleep of consistently left- versus consistently right-handed individuals. The basic pattern of results here and in previous work suggests that individual differences in sleep architecture are influenced by both degree and direction of handedness. Handedness differences in sleep architecture may reflect individual differences in cerebral organization on one hand and sleep stage mediated differences in cerebral interaction on the other.