Temporal course of perceived vowel duration.

The current study explored the temporal course of the perception of vowel duration. A backward recognition masking paradigm was employed in which the subject was to determine which of two target vowels, differing only in duration, was presented on a given trial. The target was followed, after a variable silent intervowel interval, by a masking vowel having one of three possible durations. Subjects were instructed either to identify the long vowel as /i/ and the short vowel as /I/, or were told that the targets were nonsense sounds they were to identify as long or short. For both instruction conditions, identification of the long target improved consistently with increases in the intervowel interval, whereas identification of the short target was equally accurate at the long and the short intervals. Identification of the long target vowel was most accurate when followed by a long masking vowel, whereas identification of the short target vowel was most accurate when followed by a short masking vowel. An information-processing model provided a good description of the quantitative results.