El efecto magnético en la percepción de las vocales españolasEstudio perceptivo sobre la vocal /i/

Zusammenfassung

The perceptual magnet effect is a phenomenon that recent investigations reveal problematic (Lively & Pisoni, 1997; Lotto, Kluender, & Holt, 1998). According to Kuhl (1991), a magnet effect occurs when discrimination around the best exemplar of a phonetic category is worse than discrimination around a poor exemplar of the category. However, when this effect has been clearly found, the possibility of some cross-category comparison is not discarded. In this study the perceptual magnet effect was searched for Spanish language. In this work we have assuring that all discrimination judgments were made inside a single category. Three experiments were performed with Spanish speaking adults. In Experiment 1, participants categorized 49 synthetic vowels, varying in the frequency of the first (F1) and second formant (F2). Data allowed us to establish the perceptual area of Spanish /i/ vowel. In Experiment 2, subjects rated the goodness of each variant of /i/ on a scale from 1 to 7. The data showed a graded internal structure and that finding allowed us to select a prototype (P) and a non-prototype (NP) of the /i/ category. In Experiment 3, a Same-Different (AX) discrimination task was performed around P and NP, inside of the formant space of /i/, and using signal detection theory to assess discrimination in both conditions. Results based in a bias-free measure (dprime) did not support the perceptual magnet effect and revealed the listeners showed similar sensitivity around P than around NP. Also, generalization scores were not different in both conditions. This finding suggests that the magnet effect is not a robust and universal phenomenon in speech perception. Our results don�t agree with those in which the magnet effect was found. We attributed those findings to the involvement of several phonetic categories