Evaluating the Validity of Gazepoint GP3 HD in Assessing Listening Effort: A Pupillometry Study.

Purpose: Individuals with hearing loss typically experience greater listening effort, which is the additional recruitment of cognitive/mental resources such as attention and memory to understand speech and can be aversive and tiring. Reducing effort is an important goal of the hearing health care industry. Pupillometry is an objective and increasingly popular measure of listening effort, but gold standard measures of pupil size are expensive and unwieldy. The purpose of this study was to compare a low-cost and portable pupillometry device (Gazepoint GP3 HD) to a more traditional gold standard pupillometry tool (EyeLink 1000) for indexing listening effort via pupil size.

Method: Twenty normal-hearing young adults (age range: 18-23 years) were recruited in this study. Participants' pupil size was measured using the Gazepoint and EyeLink pupillometry devices while listening to Hearing in Noise Test sentences in stationary speech-shaped noise at signal-to-noise ratios (SNRs) ranging from -8 to +8 dB.

Results: Participants' word report accuracy increased from approximately 12% to 100% when the SNRs increased from -8 to +8 dB. Peak pupil diameter decreased for both devices and was smaller with the Gazepoint device. Data quality was comparable for the two devices.

Conclusion: Gazepoint appeared to be an effective pupillometry device that records pupil dilation across a wide range of SNRs, without interfering with the auditory task.