Arabic consonant length perception depends on the relative speech rate of the distal context

Listeners adapt to the speech rate of talkers. Many studies of speech rate adaptation have focused on the influence of rate information on the perception of word segmentation or segmental perception in English. The effects of immediately adjacent (i.e., proximal) information are generally strong on the perception of both segments and segmentation, but the effects of rate information temporally remote from (i.e., distal to) ambiguous speech signals are less clear, especially for segments. The present study examines the influence of distal rate adaptation on the perception of geminate consonants in Arabic that straddle a morpheme boundary (i.e., heteromorphemic geminates). Participants heard sentences that at one point were ambiguous to the presence of the Arabic definite clitic al, which, under certain circumstances, can be realized as gemination of the subsequent word-initial consonant. The sentences were either recorded with or without the clitic and with three possible distal speech rates in the context of the clitic. They transcribed the sentences and reported what they heard, and those transcriptions were analyzed for the contribution of the original recording and the distal speech rate on the perception of al. It was found that the perception of geminates in Arabic is rate dependent. This extends the knowledge of the effects of distal rate cues to Arabic, showing that Arabic geminate consonants are perceived relative to the rate of the distal context.