Mmm whatcha say? Uncovering distal and proximal context effects in first and second-language word perception using psychophysical reverse correlation

TL;DR

This study uses a reverse-correlation method to reveal how acoustic context influences vowel perception in both first and second-language speakers, showing similar prosodic biases despite language background differences.

Contribution

It introduces a novel data-driven approach to uncover how pitch and speech rate context effects influence speech perception across different languages and timescales.

Findings

Vowel perception is affected by both proximal and distal prosodic cues.

L1 and L2 speakers show similar prosodic perception profiles.

Context effects operate over multiple timescales up to 1 second.

Abstract

Acoustic context effects, where surrounding changes in pitch, rate or timbre influence the perception of a sound, are well documented in speech perception, but how they interact with language background remains unclear. Using a reverse-correlation approach, we systematically varied the pitch and speech rate in phrases around different pairs of vowels for second language (L2) speakers of English (/i/-/I/) and French (/u/-/y/), thus reconstructing, in a data-driven manner, the prosodic profiles that bias their perception. Testing English and French speakers (n=25), we showed that vowel perception is in fact influenced by conflicting effects from the surrounding pitch and speech rate: a congruent proximal effect 0.2s pre-target and a distal contrastive effect up to 1s before; and found that L1 and L2 speakers exhibited strikingly similar prosodic profiles in perception. We provide a novel method to investigate acoustic context effects across stimuli, timescales, and acoustic domain.