Children's listening effort for L2-accented speech

Abstract

Speech perception is a complex task that can become challenging in certain conditions, such as listening to speech in unfamiliar accents. Using task-evoked pupillary response (TEPR) and dual-task procedures, prior research has shown that adults recruit additional cognitive resources when processing fully intelligible L2-accented speech compared to speech in their own L1 accent (McLaughlin and Van Engen, 2020; Brown et al., 2020). In the current study, we used pupillometry to investigate this effect in children (n = 35, ages 5;0 – 8;11) and ask whether prosodic variation can explain any differences in listening effort. Using Growth Curve Analysis, we found that unlike adults, children do not appear to recruit extra cognitive resources to process intelligible L2-accented speech. Like adults, however, pupillary response declined more rapidly for L2-accented speech across the experiment than for L1-accented speech, indicating either rapid adaptation or fatigue. Additionally, we identified three prosodic measures (relative word duration, pitch stability, and pitch range) that were related to speech adaptation/fatigue for both accent conditions, but in opposite directions. Although children do not appear to upregulate listening effort for L2-accented speech like adults, they appear to use prosodic cues differently for L1- versus L2- accented speech as they adapt to speech.