Hearing loss does not change the psychometric function’s 12-dB detection range

Evidence

The span of the psychometric function in dB drives the selection of the parameters of the modified Hughson–Westlake procedure. Without knowing the shape of the psychometric function, we could not determine the appropriate parameters for implementation of the procedure. As a result, the modified Hughson–Westlake procedure sufficiently samples the psychometric function to obtain a threshold. To see the reasons for this, we first look back to Figure 2–12, where we observe that the psychometric function for detecting a tone in quiet has a range of approximately 12 dB (the dB values that encompass about 5%–95% detections). Although this psychometric function represents that of a normalhearing listener detecting a pure tone in quiet, the range of a psychometric function for detection does not change in the presence of hearing loss (Marshall & Jesteadt, 1986). — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 307

Categorization

• XREF: Builds on this book’s psychometric function coverage and the Marshall & Jesteadt citation from earlier passages. — connects to: Elevated gap detection thresholds in hearing loss stem from threshold elevation, not temporal pathology — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 964; Reduced target audibility, not spatial processing loss, explains much of the hearing-loss speech deficit — Dijk, Pim van, Physiology, Psychoacoustics and…, 1719; Hearing loss impairs frequency selectivity beyond what stimulus level differences explain. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 558 (+1 more)
• QUESTION: Why does hearing loss not flatten or steepen the psychometric function? Worth checking the original Marshall & Jesteadt findings.
• corroborated: 2 independent passages support this claim — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 307

Broader Connections

• Hearing loss impairs frequency selectivity beyond what stimulus level differences explain. #expands (0.78) — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 558
• Reduced target audibility, not spatial processing loss, explains much of the hearing-loss speech deficit #complicates (0.75) — Dijk, Pim van, Physiology, Psychoacoustics and…, 1719
• Hearing aids address audibility, recruitment, and noise but not resolution deficits #expands (0.72)