Subject: INCREMENT DECREMENT From: Bibikov <bibikov@xxxxxxxx> Date: Mon, 12 Nov 2007 16:46:17 +0300 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>Dear colleagues. May be you will be interested in my results obtained during recording the firing activity of the midbrain units of the frog and also in the preliminary psychophysical monitoring. Stimuli were 50 ms cosine increments and decrements of the continuos tone without any transients. The main results are: 1. In continuous regime (after tens seconds of sound duration) the majority of the units responded both to increments and decrements 2. In the majority of the units these reactions were much more vigorous then the responses to the same transients with delay < 1 s from the beginning of the tone. 2. Response to the decrement usually has higher thresholds (difference 0-4dB) and was weaker. This response have been evoked by the intensity rise from the minimum to standard level (it was proved by the dependence of the latency upon the decrement duration). 3. The strong (50ms,100%)decrement in continuous state practically all subjects perceived as a transient change or even transient increase in loudness References: 1. Bibikov N.G., Grubnik O.N. Responses to intensity increments and decrements in different types of midbrain auditory units of the frog. in: "Acoustical signal processing in the central auditory system" 1997, Plenum Press:N-Y c. 271-277. 2. Bibikov N.G. Sensitivity of auditory units in the frog's midbrain to auditory decrements. J. Acoust.Soc. Amer.1999, 105, 2 pt2. 1086. 3. Bibikov N.G Neuronal responses in midbrain auditory center of the frog to amplitude changes: I AM bursts Sensory systems 1999 13. 2.p. 127-136. 4.Bibikov N.G Neuronal responses in midbrain auditory center of the frog to amplitude changes: I single amplitude events. Sensory systems 1999 13. 3. p. 179-188. 5. Bibikov N.G Neuronal response in the acoustical center of a frog to local decrements in stimulus intensity -some analog of auditory illusion and phoneme distinctions Sensory System 21 1 2007 72-86 (In Russ) -- Sincerely, Bibikov N.G. Dr. Biol. Corr.memb. RANS Main scientist. N.N.Andreyev Acoustics Institute Schvernik st. 4 Moscow 117036 Tel.: 7 499 7236311 (î) Fax : 7 495 1268411 (h) Home tel.: 7 495 1559223 e mail: bibikov@xxxxxxxx or nbibikov1@xxxxxxxx