Absolutely, that’s why I put “threshold” in quotation marks in my post. It’s important to keep in mind that since the seminal works on the application of signal detection theory to psychophysics by Tanner, Green, Swets etc. in the 1960ies, we should always be aware that there is no “threshold” in the sense that stimuli below the threshold are impossible to perceive while those above are always perceived. An important point the SDT makes is that the difference between the perceptual representation of sub- and suprathreshold stimuli is not qualitative but quantitative.
However, I know no catchy but less confusing replacements terms for “threshold” (e.g., “sound level corresponding to 71% correct detection” is certainly not an option 😉 ) – does anyone?
Daniel
From: AUDITORY - Research in Auditory Perception < > On Behalf Of Les Bernstein
Sent: Monday, November 20, 2023 4:21 PM
To: AUDITORY@xxxxxxxxxxxxxxx
Subject: Re: Estimation of auditory sensory thresholds from below: any evidence?
Of course, there is no auditory "threshold" and Dr. Dennis McFadden has argued for years that the use of the term to indicate the magnitude of the independent variable corresponding to a given level of performance is to confuse the historical background. Although he is quite correct, I have no illusions that people will retire the term. As for starting from "above," I agree with Dick. It's a more efficient way to conduct an experiment. Still, in an objective psychophysical task with feedback, one could start from below. Taking the 2-down, 1-up Levitt tracker as an example, in practice, starting from below tends to result in a bunch of "wasted" trials. The method of limits is, of course, a biased psychophysical procedure that has its own set of issues.
Les
--
Leslie R. Bernstein, Ph.D. | Professor Emeritus
Depts. of Neuroscience and Surgery (Otolaryngology) | UConn School of Medicine
263 Farmington Avenue, Farmington, CT 06030-3401
Office: 860.679.4622 | Fax: 860.679.2495
On 11/18/2023 12:30 AM, Richard F. Lyon wrote:*** Attention: This is an external email. Use caution responding, opening attachments or clicking on links. ***
I think the subject needs to feel like they're doing the job well, so starting easy (above threshold) makes sense. And they get to know very well what signal to listen for.
If you approach from below, they don't know what signal to expect, so may not be in an "optimal detector" state of mind.
Dick
On Fri, Nov 17, 2023 at 9:19 PM Massimo Grassi <massimo.grassi@xxxxxxxx> wrote:
Dear all,
I was recently writing a paper about threshold estimation in hearing and at some point I stopped.
Let suppose you are estimating a frequency discrimination threshold with a classic 2-down 1-up staircase rule (Levitt, 1971). Theoretically, you could approach the threshold from below or from above, I repeat this every year to 1st year students when I teach them the method of limits! In practice, however, in psychoacoustics we rarely-to-never approach the threshold from below.
Is there any reason for this "tradition"? I know the psychometric function should be symmetric below and above threshold! But this does not explain the "tradition"!
All the best from "it is almost winter" North East Italy.
m
