Perception of lexical tone across languages: evidence for a linguistic mode of processing

Pairs of Thai tones were presented for perceptual discrimination in three linguistic contexts [normal speech, low-pass filtered speech, and as musical (violin) sounds] to tonal language speakers, Thai and Cantonese, and non-tonal (English) language speakers. English speakers discriminated the tonal contrasts significantly better in the musical context than in filtered speech, and in filtered speech better than in full speech. On the other hand, both Thai and Cantonese speakers perceived the tonal contrasts equally well in all three contexts. Thus, developmental absence of exposure to lexical tone results in a linguistic mode of processing which involves the attenuation of a basic psychoacoustic ability, pitch discrimination.