辅音和元音知觉中的启动效应差异

The Differences of Priming Effects in the Perception of Consonant and Vowel Categories

采用启动范式,在两个实验中分别考察了辅音和元音知觉中的启动效应。启动音是纯音和言语声音,目标音是辅音范畴和元音范畴连续体。结果发现,辅音连续体知觉的范畴反应百分比受到纯音和言语启动音影响,反应时只受言语启动音影响;元音连续体知觉的范畴反应百分比不受两种启动音影响,反应时受到言语启动音影响。实验结果表明,辅音和元音知觉中的启动效应存在差异,这为辅音和元音范畴内在加工机制的差异提供了新证据。

Phonetic category is an important concept in speech perception. Generally, phonetic categories include consonant and vowel categories. Inphonetics, these two categories have many differences in the acoustic and articulatory features. Using the priming paradigm, the present study aimedto explore the differences of priming effects when perceiving the consonant and vowel continua. With non-speech and speech sounds as the primingsounds, the consonant or vowel category continuum as the target sounds, the response time and the percentage of category response as the dependentvariables, the present study examines the priming effect differences of consonant and vowel perception with two experiments. In Experiment 1, the priming effect of consonant perception was examined. The target sound was a Chinese stop contrast continuum,/ta/-/ka/,which was synthesized by varying the onset frequency of F3 （the third formant） transition. The priming sounds were two non-speech sine-wave tonesand two speech sounds. The frequency of two tones was equal to the F3 onset frequency of/ta/and/ka/respectively. The onset 100ms segments of/ta/and/ka/acted as two speech priming sounds. Participants were asked to identify the target sounds by pressing buttons labeled with ＂da＂ or ＂ga＂ asquickly as possible. The results showed that both pure tones and speech primes influenced the percentage of consonant identification, pure tone primesincreased the response of spectral-matched consonant categories, while speech primes increased the response of spectral-opposed consonant categories.In addition, only speech primes showed the priming effect in response time for spectral-matched categories. In Experiment 2, the priming effect of vowel perception was examined. The target sound was a Chinese vowel category continuum,/a/-/e/. Thepriming sounds were two pure tones and two speech sounds. The frequency of two pure tones was set at the F2 frequency of/a/and/e/respectively.The onset lOOms segments of/a/and/e/served as speech primes. The results indicated that neither pure tone nor speech primes affected the percentageof vowel identification, but speech primes showed the priming effect in response time. The results indicated that the priming effects of consonant and vowel categories were different. For consonant categories, the category judgmentwas more easily affected by prior priming sounds, but the speed of category identification was not easily influenced by spectrally partial-matchedprimes. For vowel categories, the speed of category identification was susceptible to the primes, but the category judgment was resistant to theinfluence of primes. Some researchers suggested that the perceptual traces of consonant categories （rapid-changing sounds） would decay faster thanthose of vowel categories （steady-state sounds）, and the perception of consonants may rely more on the category labels. So it seems that the categoryjudgment of rapid-changing sounds is easily influenced by contextual sounds because of the fast decay of perceptual traces and more reliance oncategory labels, while the speed of category identification of steady-state sounds is easily affected by context sounds for its clear perceptual traces.