Re: By any other name... (Yoshitaka Nakajima )

Subject: Re: By any other name...
From:    Yoshitaka Nakajima  <nakajima@xxxxxxxx>
Date:    Fri, 23 Mar 2007 00:02:58 +0900

Dear Bruno, I have a little bit philosophical answer. You can think that the sound is "either present or absent." What is really interesting is that the perceptual system seems to prefer one of the solutions in some contexts. Probably, we need an explanation at a higher level, at least in some cases. Now, there is a case, where we definitely need such an explanation. My colleagues and I recently reported an auditory phenomenon where a glide tone with a real temporal gap, where there is no sound energy, can be perceived reasonably continuous: Gerard Remijn, Yoshitaka Nakajima, and Shunsuke Tanaka, "Perceptual completion of a sound with a short silent gap," Perception (in press). Because the paper is still in press, I would like to show you the abstract here: Abstract Listeners reported the perceptual completion of a sound in stimuli consisting of two crossing frequency glides of unequal duration that shared a short silent gap (40 ms or less) at their crossing point. Even though both glides shared the gap, it was consistently perceived only in the shorter glide, whereas the longer glide could be perceptually completed. Studies on perceptual completion in the auditory domain reported so far have shown that completion of a sound with a gap occurs only if the gap is filled with energy from another sound. In the stimuli used here, however, no such substitute energy was present in the gap, showing evidence for perceptual completion of a sound without local stimulation ('modal' completion). The results show that the perceptual completion of the long glide occurred under both monaural and dichotic presentation of the gap-sharing glides, and therefore involves central stages of auditory processing. The inclusion of the gap in the short glide, rather than in both the long and the short glide, is explained in terms of auditory event and stream formation. Best regards, Yoshitaka Yoshitaka NAKAJIMA, PhD Professor, Dept. of Acoustic Design Kyushu University Fukuoka 815-8540, Japan Telephone: +81 92 553 4558 Facsimile: +81 92 553 4520 nakajima@xxxxxxxx ----- Original Message ----- From: "Bruno Repp" <repp@xxxxxxxx> To: <AUDITORY@xxxxxxxx> Sent: Thursday, March 22, 2007 11:08 PM Subject: Re: By any other name... > Dear Richard: > > There is a philosophical (or methodological?) problem I've had with > this effect for a long time: If, as you say, "the interrupting louder > sound stimulates the same peripheral receptors that would have been > stimulated if the sound had indeed been present", what proves that > the sound is actually absent? > > Best, > Bruno > > >The auditory continuity phenomenon has been the subject of several > >communications earlier this month, and several names of people > >associated with this illusion were mentioned. Massimo Grassi > >correctly stated that Vicario's name belongs on the list. He did > >indeed observe the effect in 1960, naming it "L'effetto tunnel > >acustico." But Miller and Licklider seem to have been the first > >discoverers in 1950. Several other investigators, unaware of the > >earlier publications, made their own independent discoveries. This > >led to a multiplicity of terms describing the effect including > >"picket fence effect," "auditory figure ground effect," and more > >recently, "auditory continuity effect," "auditory induction," and > >"temporal induction." > > > >The communications this month seem to have limited this phenomenon > >to the illusory continuity of steady-state tones and tone glides > >through interruptions by a louder noise. But this phenomenon is > >much broader: portions of any sound can be restored if the > >interrupting louder sound stimulates the same peripheral receptors > >that would have been stimulated if the sound had indeed been > >present. In everyday life this effect represents a sophisticated > >process that can restore portions of signals (including speech) if > >they have actually been masked. This is accomplished by > >reallocating a portion of the neural representation of the louder > >interrupting sound for the perceptual synthesis of the fainter > >signal. In support of this mechanism, it had been shown that when > >illusory restoration of the fainter sound (either a tone or speech) > >occurred, it was accompanied by a decrease in the loudness of the > >interrupting sound [R.M. Warren et al., 1994, Auditory induction: > >Reciprocal changes in alternating sounds. Perception and > >Psychophysics, 55, 313-322]. > > > >For a review of the literature, see Chapter 6 "Perception of missing > >sounds" in R.M. Warren, 1999, Auditory Perception: A New Analysis > >and Synthesis, New York: Cambridge University Press (a third > >edition is now in production by Cambridge). > > > -- > Bruno H. Repp > Haskins Laboratories > 300 George Street > New Haven, CT 06511-6624 > Tel. (203) 865-6163, ext. 236 > Fax (203) 865-8963 > > > NOTE: I am at Rutgers University, Newark, two days each week, > usually Wednesday and Friday, and don't read my > Haskins e-mail on those days. To reach me at Rutgers, send > e-mail to <repp@xxxxxxxx>. >

This message came from the mail archive
maintained by:
DAn Ellis <>
Electrical Engineering Dept., Columbia University