“…Between 2019 and 2021, Clarivate's Web of Science database lists a total of 239 articles with the term "listening effort" in the title, abstract, or keywords. Among these articles, 35% (81) employed at least one physiological measure to examine listening effort; 7% (16) employed more than one physiological measure. The variety of measures used was large, and included measures directly indexing brain activity, such as electroencephalogram (EEG) alpha oscillations, 1,2 EEG-evoked potential components, 3,4 functional near-infrared spectroscopy (fNIRS), 5,6 and peripheral measures, such as skin conductance, 7,8 pupil diameter, 9,10 heart rate variability, 11,12 and cardiovascular preejection period.…”