The effect of clear speech on dual-task measures of listening effort in varied noise levels
Listener-oriented clear speech (CS) improves word recognition in noise compared to conversational speech (CO). Pupillometry studies suggest that this intelligibility benefit may result from reduced listening effort, reflecting differences in how cognitive resources are allocated during challenging listening tasks. Dual-task paradigms demonstrate validity at measuring listening effort (Brown, 2025); however, previous studies have not consistently shown a CS benefit in response times on secondary visual tasks (Meemann and Smiljanić, 2019). The current study evaluates whether a CS benefit on visual task response time, and thus listening effort, emerges across different noise levels: quiet, 0 dB signal-to-noise ratio (SNR), and −5 dB SNR. Native English listeners performed a word recognition in noise task and a visual Stroop task, first separately and then simultaneously. Preliminary results show improved word recognition and slower response time with increased noise levels for CS but not for CO. However, response time did not improve with CS at any noise level. Thus, it appears that CS does not provide a measurable benefit for dual-task measures of listening effort, suggesting that cognitive resources may not be more available for the visual task when listening to the more intelligible CS.