Re: [AUDITORY] Finding from Greenwood, 1961

["Richard F. Lyon" <dicklyon@xxxxxxx>]

Don was living in Hayward, California, in '07.  We had some emails about ear club and Stanford talks and other stuff, and I saw him around a few times that year, and he sent me a bunch of papers, including some unpublished, in October of '07.  But he didn't respond to my November emails.  Is that when he moved north?

Dick

On Sun, Nov 7, 2021 at 8:04 AM PIerre DIVENYI <pdivenyi@xxxxxxxxxxxxxxxxxx> wrote:

It was decades ago that I last heard from Don. He moved to northern Washington in order to be close to British Columbia from where he derived his ridiculously low retirement. I would be surprised if he were still with us, were he, he would be close to 100. He was a miscast at the UBC Dept. of Speech and Hearing entirely focused on turning out hordes of speech pathologists. In any case, he is/was one of the auditory scientist to whose views I always listened. He also had the gift of being able to clearly explain complex ideas.

Pierre

Sent from my autocorrecting iPad

On Nov 7, 2021, at 00:08, Richard F. Lyon <dicklyon@xxxxxxx> wrote:



The last time I pinged Don Greenwood at <ddg@xxxxxxxxxx> I got a bounce.  Does anyone know if he's still with us?  It would be interesting to get his comments on this question.

I would address the question in terms of the change of bandwidth with level through that middle region, and see if the described result is explainable by level-dependent auditory filter models.

Dick

On Sat, Nov 6, 2021 at 9:28 PM Hornsby, Benjamin Wade Young <ben.hornsby@xxxxxxxx> wrote:

Hi All,

I am hoping to pick the brains of those more knowledgeable about this than I am. I am reading some classic masking papers with a doctoral student and we have a question about a finding reported by Greenwood (1961).

 

Greenwood, D. D. (1961). Auditory masking and the critical band. The journal of the acoustical society of America, 33(4), 484-502.

https://asa.scitation.org/doi/abs/10.1121/1.1908699?casa_token=5nyI-2IWfCUAAAAA:F_c_w65ZXWcIQE4SDr-qrEcGTLJ9QUtRChx4B2t4rOAdEv8_PJ3wKhHxvfNCaOwJ0EjucY_H0J3roQ

 

In this paper Greenwood examined critical bandwidths using a band widening masking paradigms to measure “masked audiograms” as he systematically widened the bandwidth of a masking noise.  In one experiment he looked at growth of masking for his masked audiograms by systematically increasing the spectrum level (and overall level) of the various noise bands. He did this for noise bands that were narrower and wider than the critical bandwidth.

 

For noise bandwidths that were greater than the critical band he showed a linear growth of masking for tones centered in the noise band (i.e., linear in band masking). However, when the noise bandwidth was less than the critical bandwidth, growth of masking showed a “jog” in the growth of masking function for tones centered in the narrow noise band. That is masked threshold appeared to decrease (~3 dB) as noise power increased when the level of the noise reached what he called a “transition level” of around 50 dB sensation level. However, as levels increased above this “transition” level, growth of masking again seemed linear. Figure 6 on p. 493 of the paper shows the finding I am talking about.

 

It would not be the first time I misinterpreted an older (and newer) paper so I am probably just missing something. However, I was not familiar with this finding and wondered if others were aware of it and had thoughts on why it occurred.

 

Thanks,

 

Ben