Abstract
The Possible-word Constraint (PWC) limits the number of lexical candidates considered for a given input by stipulating that the input should be parsed into a string of feasible words (Norris et. al., 1997). Any segmentation resulting in impossible word candidates (i.e. an isolated single consonant) is disfavored. Four experiments using the head-turn preference procedure investigated whether 12-month-olds observe the PWC to aid them in word recognition. In the first two experiments, infants were familiarized with lists of words (e.g. "rush"), then tested on lists of nonsense items containing these words in "possible" or "impossible" positions (e.g. "niprush" [nip+rush - possible] or "prush" [p+rush - impossible]). In the other experiments, 12-month-olds were similarly familiarized with lists of words, but test items occurred in sentential contexts; this condition more readily taxed online segmentation abilities. In the first 2 experiments, 12-month-olds listened significantly longer to targets in "possible" versus "impossible" contexts when targets occurred at the end of nonsense items, but not when they occurred at the beginning. In Experiments 3 and 4, infants listened significantly longer to words in the "possible" condition regardless of target location. These results suggest that 12-month-olds, like adults, use the PWC during online word recognition.
