Within the field of hearing science, pupillometry is a widely used method for quantifying listening effort. Its use in research is growing exponentially, and many labs are (considering) applying pupillometry for the first time. Hence, there is a growing need for a methods paper on pupillometry covering topics spanning from experiment logistics and timing to data cleaning and what parameters to analyze. This article contains the basic information and considerations needed to plan, set up, and interpret a pupillometry experiment, as well as commentary about how to interpret the response. Included are practicalities like minimal system requirements for recording a pupil response and specifications for peripheral, equipment, experiment logistics and constraints, and different kinds of data processing. Additional details include participant inclusion and exclusion criteria and some methodological considerations that might not be necessary in other auditory experiments. We discuss what data should be recorded and how to monitor the data quality during recording in order to minimize artifacts. Data processing and analysis are considered as well. Finally, we share insights from the collective experience of the authors and discuss some of the challenges that still lie ahead.

Recognizing speech in difficult listening conditions requires considerable focus of attention that is often demonstrated by elevated activity in putative attention systems, including the cingulo-opercular network. We tested the prediction that elevated cingulo-opercular activity provides word-recognition benefit on a subsequent trial. Eighteen healthy, normal-hearing adults (10 females; aged 20 -38 years) performed word recognition (120 trials) in multi-talker babble at ϩ3 and ϩ10 dB signal-to-noise ratios during a sparse sampling functional magnetic resonance imaging (fMRI) experiment. Blood oxygen level-dependent (BOLD) contrast was elevated in the anterior cingulate cortex, anterior insula, and frontal operculum in response to poorer speech intelligibility and response errors. These brain regions exhibited significantly greater correlated activity during word recognition compared with rest, supporting the premise that word-recognition demands increased the coherence of cingulo-opercular network activity. Consistent with an adaptive control network explanation, general linear mixed model analyses demonstrated that increased magnitude and extent of cingulo-opercular network activity was significantly associated with correct word recognition on subsequent trials. These results indicate that elevated cinguloopercular network activity is not simply a reflection of poor performance or error but also supports word recognition in difficult listening conditions.

Listening to speech in noise can be exhausting, especially for older adults with impaired hearing. Pupil dilation is thought to track the difficulty associated with listening to speech at various intelligibility levels for young and middle-aged adults. This study examined changes in the pupil response with acoustic and lexical manipulations of difficulty in older adults with hearing loss. Participants identified words at two signal-to-noise ratios (SNRs) among options that could include a similar-sounding lexical competitor. Growth Curve Analyses revealed that the pupil response was affected by an SNR-by-lexical competition interaction, such that it was larger and more delayed and sustained in the harder SNR condition, particularly in the presence of lexical competition. Pupillometry detected these effects for correct trials and across reaction times, suggesting it provides additional evidence of task difficulty than behavioral measures alone.

Age-related hearing loss, or presbyacusis, is a major public health problem that causes communication difficulties and is associated with diminished quality of life. Limited satisfaction with hearing aids, particularly in noisy listening conditions, suggests that central nervous system declines occur with presbyacusis and may limit the efficacy of interventions focused solely on improving audibility. This study of 49 older adults (M069.58, SD08.22 years; 29 female) was designed to examine the extent to which low and/or high frequency hearing loss was related to auditory cortex morphology. Low and high frequency hearing constructs were obtained from a factor analysis of audiograms from these older adults and 1,704 audiograms from an independent sample of older adults. Significant region of interest and voxel-wise gray matter volume associations were observed for the high frequency hearing construct. These effects occurred most robustly in a primary auditory cortex region (Te1.0) where there was also elevated cerebrospinal fluid with high frequency hearing loss, suggesting that auditory cortex atrophies with high frequency hearing loss. These results indicate that Te1.0 is particularly affected by high frequency hearing loss and may be a target for evaluating the efficacy of interventions for hearing loss.

Hearing loss is associated with anecdotal reports of fatigue during periods of sustained listening. However, few studies have attempted to measure changes in arousal, as a potential marker of fatigue, over the course of a sustained listening task. The present study aimed to examine subjective, behavioral, and physiological indices of listening‐related fatigue. Twenty‐four normal‐hearing young adults performed a speech‐picture verification task in different signal‐to‐noise ratios (SNRs) while their pupil size was monitored and response times recorded. Growth curve analysis revealed a significantly steeper linear decrease in pupil size in the more challenging SNR, but only in the second half of the trial block. Changes in pupil dynamics over the course of the more challenging listening condition block suggest a reduction in physiological arousal. Behavioral and self‐report measures did not reveal any differences between listening conditions. This is the first study to show reduced physiological arousal during a sustained listening task, with changes over time consistent with the onset of fatigue.