| Abstract: | Used 2 tapping tasks to determine whether individual infants' right- or left-hand (RH and LH, respectively) preference for unimanual and bimanual tapping corresponded to their handedness in bimanual manipulation tasks (bimanual handedness) during the 2nd yr of life, and whether the developmental onset of a manual tapping preference occurred before or after the onset of bimanual handedness at the end of the 1st yr of life. At each of 2 age levels (15 and 22 mo, 24 Ss each), most infants demonstrated an RH preference in both tapping tasks, whether they showed bimanual right- or left-handedness. Nevertheless, a sizable minority of bimanual LH, but not RH, demonstrated an LH preference across tapping tasks. Since research with adults suggests left-hemisphere specialization for speech in almost all RH and many LH individuals, it is possible that a manual preference for tapping in infants, with appropriate empirical validation, will prove a reliable index of this specialization. In addition, 16 10-mo-olds demonstrated a manual preference in the unimanual tapping task whether they showed bimanual handedness, but few demonstrated a preference in the bimanual tapping task. This latter finding is consistent with past research using other handedness tasks with infants, which suggests that unimanual handedness precedes bimanual handedness. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
