PMID- 16015713
OWN - NLM
STAT- MEDLINE
DCOM- 20060414
LR  - 20061115
IS  - 1526-8748 (Electronic)
IS  - 1526-8748 (Linking)
VI  - 2004
DP  - 2004 Nov 30
TI  - Auditory scene analysis and sensory memory: the role of the auditory N100m.
PG  - 19
AB  - We consider the neural dynamics underlying auditory streaming, the perceptual 
      grouping of transient auditory events, by using neural modeling and 
      magnetoencephalographic (MEG) measurements in humans. We demonstrate that spatial 
      variations in the strength of feedback inhibition leads to differential amplitude 
      modulation (AM) tuning resembling that found in animal models. In our model, 
      neurons respond selectively to stimuli presented at different onset-to-onset 
      interstimulus intervals (ISIs), and their summed activity (corresponding to the 
      MEG signal) exhibits both transient and sustained responses (SRs) at fast ISIs. 
      In MEG measurements utilizing 2-s trains of 50-ms stimuli presented at 0-1950 ms 
      ISIs, we observed the transient N100m and SRs predicted by the model, with a 
      prominent SR emerging for discrete stimuli at ISIs below 200 ms. Our results 
      explain why, at fast stimulus rates, the amplitude of the auditory N100m appears 
      to be strongly attenuated even though auditory cortex continues to respond 
      vigorously to the stimuli. The results suggest that the longer and shorter forms 
      of auditory sensory memory may be reflected in the N100m and the SR, 
      respectively. As the emergence of the SR coincides with the stimuli being 
      perceived as auditory streams, our study suggests that auditory sensory memory as 
      indexed by transient and sustained cortical activity might underlie auditory 
      scene analysis.
FAU - May, P J C
AU  - May PJ
AD  - Apperception and Cortical Dynamics, Department of Psychology, University of 
      Helsinki, Finland. patrick.may@helsinki.fi
FAU - Tiitinen, H
AU  - Tiitinen H
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20041130
PL  - United States
TA  - Neurol Clin Neurophysiol
JT  - Neurology & clinical neurophysiology : NCN
JID - 100972440
SB  - IM
MH  - Acoustic Stimulation/*methods
MH  - Analysis of Variance
MH  - Auditory Cortex/*physiology
MH  - Auditory Perception/*physiology
MH  - Evoked Potentials, Auditory/*physiology
MH  - Humans
MH  - Memory/*physiology
EDAT- 2005/07/15 09:00
MHDA- 2006/04/15 09:00
CRDT- 2005/07/15 09:00
PHST- 2005/07/15 09:00 [pubmed]
PHST- 2006/04/15 09:00 [medline]
PHST- 2005/07/15 09:00 [entrez]
PST - epublish
SO  - Neurol Clin Neurophysiol. 2004 Nov 30;2004:19.