Auditory perception of temporal order: A comparison between tonal language speakers with and without non-tonal language experience.

It has been shown recently that temporal order perception is modulated by language environments. The present study focused on the specific question whether a secondary language experience influences temporal order perception by comparing the temporal order thresholds (TOTs) between Chinese subjects with and without a secondary non-tonal language (i.e., English) experience. Besides monaurally presented paired clicks, binaurally presented two different types of tone pairs were used in order to better capture a potential difference between tonal and non-tonal languages. The results showed a non-significant language effect on monaurally presented click TOTs, but a significant language effect for binaurally presented tone TOTs. Compared to click performance, Chinese subjects without English proficiency demonstrated a significantly lower TOT only for close frequency tone pairs, while Chinese subjects with English proficiency demonstrated lower TOTs for both close frequency and distant frequency tone pairs. These results confirm on the one hand a common and language independent temporal mechanism for perceiving the order of two monaurally presented stimuli, and indicate on the other hand specific mechanisms of neuronal plasticity for perceiving the order of frequency-related auditory stimuli for tonal language speakers with or without a secondary non-tonal language experience.