Listening Effort by Native and Nonnative Listeners Due to Noise, Reverberation, and Talker Foreign Accent During English Speech Perception

Abstract

Purpose Understanding speech in complex realistic acoustic environments requires effort. In everyday listening situations, speech quality is often degraded due to adverse acoustics, such as excessive background noise level (BNL) and reverberation time (RT), or talker characteristics such as foreign accent ( Mattys, Davis, Bradlow, & Scott, 2012 ). In addition to factors affecting the quality of the input acoustic signals, listeners' individual characteristics such as language abilities can also make it more difficult and effortful to understand speech. Based on the Framework for Understanding Effortful Listening ( Pichora-Fuller et al., 2016 ), factors such as adverse acoustics, talker accent, and listener language abilities can all contribute to increasing listening effort. In this study, using both a dual-task paradigm and a self-report questionnaire, we seek to understand listening effort in a wide range of realistic classroom acoustic conditions as well as varying talker accent and listener English proficiency. Method One hundred fifteen native and nonnative adult listeners with normal hearing were tested in a dual task of speech comprehension and adaptive pursuit rotor (APR) under 15 acoustic conditions from combinations of BNLs and RTs. Listeners provided responses on the NASA Task Load Index (TLX) questionnaire immediately after completing the dual task under each acoustic condition. The NASA TLX surveyed 6 dimensions of perceived listening effort: mental demand, physical demand, temporal demand, effort, frustration, and perceived performance. Fifty-six listeners were tested with speech produced by native American English talkers; the other 59 listeners, with speech from native Mandarin Chinese talkers. Based on their 1st language learned during childhood, 3 groups of listeners were recruited: listeners who were native English speakers, native Mandarin Chinese speakers, and native speakers of other languages (e.g., Hindu, Korean, and Portuguese). Results Listening effort was measured objectively through the APR task performance and subjectively using the NASA TLX questionnaire. Performance on the APR task did not vary with changing acoustic conditions, but it did suggest increased listening effort for native listeners of other languages compared to the 2 other listener groups. From the NASA TLX, listeners reported feeling more frustrated and less successful in understanding Chinese-accented speech. Nonnative listeners reported more listening effort (i.e., physical demand, temporal demand, and effort) than native listeners in speech comprehension under adverse acoustics. When listeners' English proficiency was controlled, higher BNL was strongly related to a decrease in perceived performance, whereas such relationship with RT was much weaker. Nonnative listeners who shared the foreign talkers' accent reported no change in listening effort, whereas other listeners reported more difficulty in understanding the accented speech. Conclusions Adverse acoustics required more effortful listening as measured subjectively with a self-report NASA TLX. This subjective scale was more sensitive than a dual task that involved speech comprehension, which was beyond sentence recall. It was better at capturing the negative impacts on listening effort from acoustic factors (i.e., both BNL and RT), talker accent, and listener language abilities.

Moderate Reverberation Does Not Increase Subjective Fatigue, Subjective Listening Effort, or Behavioral Listening Effort in School-Aged Children

“…Finally, it is possible that moderate reverberation does not increase behavioral listening effort, contrary to the expectations outlined in the existing frameworks. This final possibility is based on converging lines of emerging evidence, such as increased listening effort with the addition of acoustic paneling (Amlani and Russo, 2016), non-significant effects with behavioral paradigms (Picou et al, 2016; Peng and Wang, 2019), and differential physiological effects of noise and distortion (Francis et al, 2016). In some cases, the reverberation affected word recognition performance but did not have a comparable detrimental effect on listening effort (Peng and Wang, 2016, 2019; Picou et al, 2016).…”

“…This final possibility is based on converging lines of emerging evidence, such as increased listening effort with the addition of acoustic paneling (Amlani and Russo, 2016), non-significant effects with behavioral paradigms (Picou et al, 2016; Peng and Wang, 2019), and differential physiological effects of noise and distortion (Francis et al, 2016). In some cases, the reverberation affected word recognition performance but did not have a comparable detrimental effect on listening effort (Peng and Wang, 2016, 2019; Picou et al, 2016). If future studies continue to demonstrate results contrary to framework predictions, it will be necessary to update the FUEL (Pichora-Fuller et al, 2016) and ELU framework (Rönnberg et al, 2013).…”

“…For adults with normal hearing, several investigators have reported that increased levels of reverberation result in increased listening effort, as measured via subjective ratings with recorded stimuli (Sato et al, 2008, 2012; Rennies et al, 2014). However, other investigators using behavioral paradigms have failed to demonstrate increased listening effort with moderate increases in reverberation (Picou et al, 2016; Peng and Wang, 2019). For example, Picou et al (2016) found that increasing reverberation (from <100 to 475 or to 834 ms), did not increase listening effort for adults with normal hearing.…”

Speech intelligibility and listening effort in university classrooms for native and non-native Italian listeners

“…A similar pattern of increased effort at matching performance levels was also found when pupillometry was used to measure LE, with reference to a sentence-processing task. 21 Differently, in Peng and Wang, 22 LE results mirrored the performance changes in a speech comprehension task (i.e. higher LE and lower accuracy for non-native compared to native listeners).…”

Effortful listening under the microscope: examining relations between pupillometric and subjective markers of effort and tiredness from listening.

“…Subjective effort ratings were an adapted version of the NASA task load index item assessing mental demand (Hart & Staveland, 1988), a commonly used subjective measure of effort (Dimitrijevic et al, 2019;McGarrigle et al, 2017;Pals et al, 2019;Peng & Wang, 2019;Strand et al, 2018). Finally, we assessed subjective performance evaluation as follows;…”