Bengali nasal vowels: lexical representation and listener perception

This paper focuses on the question of the representation of nasality as well as speakers' awareness and perceptual use of phonetic nasalisation by examining surface nasalisation in two types of vowels in Bengali: underlying nasal vowels (CṼC) and nasalised vowels before a nasal consonant (CVN). A series of three cross-modal forced-choice experiments was used to investigate the hypothesis that only unpredictable nasalisation is stored and that this sparse representation governs how listeners interpret vowel nasality. Visual full-word targets were preceded by auditory primes consisting of CV segments of CVC words with nasal vowels ([tʃɑ̃] for [tʃɑ̃d] 'moon'), oral vowels ([tʃɑ] for [tʃɑl] 'unboiled rice') or nasalised oral vowels ([tʃɑ̃(n)] for [tʃɑ̃n] 'bath') and reaction times and errors were measured. Some targets fully matched the prime while some matched surface or underlying representation only. Faster reaction times and fewer errors were observed after CṼC primes compared to both CVC and CVN primes. Furthermore, any surface nasality was most frequently matched to a CṼC target unless no such target was available. Both reaction times and error data indicate that nasal vowels are specified for nasality leading to faster recognition compared to underspecified oral vowels, which cannot be perfectly matched with incoming signals.