Auditory representation of vowel quality.
Andrew B. Wallace, Sheila E. Blumstein · The Journal of the Acoustical Society of America · 2009
It is generally assumed that the early stages of speech perception involve the extraction of some kind of generalized auditory patterns or properties from the peripheral input. The auditory representation that results is of considerable interest, since it serves as the input to higher-level, speech specific processes of phonetic perception. The current research examines this auditory representation using a priming paradigm, in which perception of vowel targets is facilitated when the targets are preceded by acoustically matched nonspeech stimuli. By manipulating the acoustic parameters of these nonspeech “prime” tones, it is possible to determine the role of these parameters in the auditory stages of vowel processing. Previous results [Wallace and Blumstein, J. Acoust. Soc. Am. 119, 3245 (2006)] suggest a short window of analysis of no more than 25 ms. In Experiment 1, frequency of nonspeech primes was varied, with results suggesting broad frequency tuning. In Experiment 2, primes matched to both F1 and F2 of the target vowels were found to elicit a greater priming effect than would be predicted by summing the response to separately presented F1 and F2 primes, suggesting that the auditory representation of vowels encodes combinations of formant frequencies.