Hemispheric asymmetry in the identification of four-letter names traced in the right and left palms

Forty right-handed males were asked to identify four-letter names traced in either the right or left palms while their eyes were closed. The name stimuli were traced in a right-side-up or upside-down orientation (i.e., vertical or rotated 180°). Mean percentage of errors served as the dependent variable. On the first block of 40 trials, the left palm/right hemisphere ( LP RH) was significantly more accurate than the right palm/left hemisphere ( RP LH) at identifying these names. This advantage, however, was only manifest when the name stimuli were traced in the upside-down orientation. On the second block of 40 trials, as the name stimuli became more familiar and the subjects became more practiced, a similar LP RH advantage was observed; however, the impact of the rotation variable was no longer in evidence (i.e., the LP RH was slightly more accurate on both upright and inverted names). These results are interpreted in light of a process-oriented tactile asymmetry as proposed by M. W. O'Boyle, F. Van Wyhe-Lawler, and D. A. Miller (1987, Brain and Cognition, 6, 474-494).