Perceptual grouping by infants and preschool children.

We tested infants 6 to 8 months and children 5? years of age for their discrimination of silent intervals between elements of auditory patterns. Standard patterns consisted of six 200-ms tones, three at 440 Hz and three at 659 Hz, with 200-ms intertone intervals (XXXOOO). Contrasting patterns differed only in the addition of a silent increment following the third tone (i.e., between tone groups, XXXOOO) or following the fourth tone (i.e., within a tone group, XXXOOO). Contrasting stimuli presented to infants had increments of 200, 125, 100, or 75 ms; those presented to children had increments of 100, 75, and 50 ms. Infants detected all increments in all locations except the 75-ms increment in the between-group location, but there were no differences in performance for different increment locations. Children detected all increments, but performed significantly worse for between-group increments than for within-group increments. Thus, the context of a temporal increment influences its detectability for children, as it does for adults, indicating that children group the elements of auditory stimuli on the basis of frequency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)