Baseline-normalized pupillometry underestimates effort from continuous degradation.

Evidence

This overall smaller increase in pupil dilation can be explained by the fact that these curves are normalized to a baseline of 200 ms preceding the presentation of each critical item per trial, participant and condition. Listening to degraded speech is by itself more effortful than listening to natural speech (e.g., Winn et al. 2015 ), and therefore there is a difference in the baseline between DS and NS. — Dijk, Pim van, Physiology, Psychoacoustics and…, 3953

Categorization

• QUESTION: Raises a methodological worry: if chronically degraded speech raises baseline pupil tone, relative-to-baseline measures may hide the true cumulative effort. Worth chasing in CI listening studies.
• XREF: Connects to the reader’s noise/silence work on chronic exposure creating baseline adaptation that masks acute responses (e.g., keynote sounds noticed only when they change).