INCREMENT DECREMENT

[Bibikov <bibikov@xxxxxxx>]

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 (о)
Fax : 7 495 1268411 (h)
Home tel.: 7 495 1559223 
e mail: bibikov@xxxxxxx  or nbibikov1@xxxxxxxxx