Left-side infant holding: A test of the hemispheric arousal-attentional hypothesis

When asked to hold a young infant in their arms, most adults field on the l eft side (Harris, 1997). In a prior study, we found the same bias when we a shed adults merely to imagine holding an infant in their arms (Harris, Alme rigi, & Kirsch, 1999). it has been hypothesized that tile left-side bias is the product of right-hemisphere arousal accompanying certain aspects of th e act, causing attention to be driven to the contralateral, or left, side o f personal space. Left-side holding, whether actual or imagined, thus would be consistent with the direction to which the holder's attention has been endogenously directed. We tested this hypothesis by giving 250 college stud ents the "imagine-holding" task and then, as an independent measure of late ralized hemispheric arousal, a 34-item Chimeric Faces Test (CFT). On the "i magine" lest, a significant majority reported a left-side hold, and, on the CFT, left-side holders had a significantly stronger left-hemispace bias th an right-side holders, although both left- and right- side holders had left -hemispace CFT biases. The results thus support the attentional-arousal hyp othesis but indicate that other factors are contributing as well. (C) 2001 Academic Press.