Neural indices of listening effort in noisy environments

Abstract

Listening in a noisy environment is challenging for individuals with normal hearing and can be a significant burden for those with hearing impairment. The extent to which this burden is alleviated by a hearing device is a major, unresolved issue for rehabilitation. Here, we found adult users of cochlear implants (CIs) self-reported listening effort during a speech-in-noise task that was positively related to alpha oscillatory activity in the left inferior frontal cortex, canonical Broca’s area, and inversely related to speech envelope coherence in the 2–5 Hz range originating in the superior-temporal plane encompassing auditory cortex. Left frontal cortex coherence in the 2–5 Hz range also predicted speech-in-noise identification. These data demonstrate that neural oscillations predict both speech perception ability in noise and listening effort.

Top-down modulation of neural envelope tracking: the interplay with behavioral, self-report and neural measures of listening effort

“…Similarly, highest alpha power was obtained at intermediate . Although increased alpha power has been associated with increased demands or effort (Obleser et al, 2012;Dimitrijevic et al, 2019), to our knowledge no research has shown a peak-shaped behavior for alpha power similar to the present study.…”

“…Finally, phase synchronization as well as alpha power were normalized per repetition, SNR and participant. In previous studies, alpha power is often normalized against a baseline period before the stimulation (Obleser et al, 2012;Dimitrijevic et al, 2019). We did not do this because we wanted to compare the five effort measures, so we normalized each measure the same way, i.e.…”

“…In contrast to phase, our results showed a peak-shaped curve for alpha power as a function of speech understanding. Although, no study has yet investigated changes in alpha power across a wide range of SNRs or SU-levels, several studies demonstrated that increased alpha is observed with increased demand or effort (Obleser et al, 2012;Miles et al, 2017;Dimitrijevic et al, 2019).…”

“…Next to phase, other EEG measures have also been associated with listening effort, e.g. alpha oscillations (Obleser et al, 2012;Miles et al, 2017;Dimitrijevic et al, 2019) or amplitude of event-related potentials (Bertoli & Bodmer, 2016). Lastly, several studies have also shown that the pupil size and eye movements can be used as physiological indicators of processing load (Zekveld et al, 2010(Zekveld et al, , 2018Koelewijn et al, 2014;Wendt et al, 2014).…”

“…Firstly, studies have shown an association between changes in these measures and changes in listening effort (alpha: Obleser et al, 2012;phase: Bernarding et al, 2014). Secondly, phase synchronization and alpha power are, in contrast to the previous effort measures, direct measures of brain activity similar to neural envelope tracking (Peelle, 2018;Dimitrijevic et al, 2019).…”