The four-way voicing distinction in Bengali infant directed speech

Abstract

Although vowels in infant-directed Speech (IDS) are thought to be hyper-articulated, findings from consonants are more mixed. Stops in languages with three- and four-way voicing distinctions, in particular, havebeen found to be hypo-articulated in IDS (Narayan and Yoon, 2011—Korean; Benders et al., 2019—Nepali) compared to adult-directed speech (ADS). We investigated the production of stops and affricates in Bengali which has a four-way voicing and aspiration distinction. IDS and ADS samples of connected speech produced by 10 native speakers (5 male and 5 female) of Bangladeshi Bengali (Yu et al., 2014) were compared. Stops and affricates were analyzed for voice onset time, onset f0 and lenition of the closure. Analyses controlled for prosodic position, lexical stress, and speaker sex—variables that are known to influence hypo-articulation. To compare the overlap between categories, acoustic measures were combined to obtain Pillai scores (Hay et al., 2006). Categories with low Pillai scores have more overlap and are thus, less distinct. The implications of the results for acquisition of phonetic categories will be discussed.