We previously introduced an adaptive psychophysical method called the adaptive scan (AS) that is readily available in the digital app PART. AS presents multiple progressive tracks (e.g., “scans”) each of which comprises a range of stimulus values whose positioning adapts based on a listener´s performance. Each scan is intended to contain trials above and below a listener´s detection or discrimination threshold for an auditory cue, which is anticipated to increase familiarity with the tested cues. Previously, AS was validated against other known adaptive psychophysical methods (e.g., up-down staircases) and the method of constant stimulus using the QUEST algorithm. QUEST allowed for targeting the same point in the psychometric function (e.g., 80% threshold) in all methods tested. However, the QUEST procedure is parametric, requires many trials, and is not easily applied to the diversity of psychophysical tests that AS can be useful for. Here, we examine a variety of alternative approaches to estimate threshold from the AS procedure. This work adds to the usability of AS in particular and psychophysical testing in general.
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