The Relation Between Sustained Listening Under Difficult Conditions and Behavioral, Subjective, and Physiological Indicators of Fatigue.

Only 20 people took part, all aged 19 to 29 and all with self-reported normal hearing, so the results say nothing about older listeners or people with hearing loss. The memory task was deliberately made demanding, and the authors say it may be too hard for older or hearing-impaired listeners. Time of day was not controlled, and pupil activity drifts naturally across the day, which could have added noise to the pupil measure. The fatigue questionnaire used only six items; the authors say that is fine for tracking change within a session but the scores should not be compared with published norms. Not everyone showed the pupil rise: in some sessions it stayed flat or fell. The authors state that the design cannot separate how hard the task was from how much effort each person chose to put in. Two people who started the study did not complete the sessions.

This work was funded by the German Research Foundation (Deutsche Forschungsgemeinschaft), project 352015383-SFB 1330 A1. The authors declared no competing interests.

Do not read this as evidence that hard listening makes people perform worse. Accuracy only fell in two of the four processing conditions, responses got faster rather than slower, and the authors say the design cannot separate task difficulty from how much effort listeners put in. None of it was tested in people with hearing loss.