Neuronal activation times to simple, complex, and natural sounds in cat primary and nonprimary auditory cortex

Centre for Brain and Mind, Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
Journal of Neurophysiology (Impact Factor: 2.89). 06/2011; 106(3):1166-78. DOI: 10.1152/jn.00940.2010
Source: PubMed


Interactions between living organisms and the environment are commonly regulated by accurate and timely processing of sensory signals. Hence, behavioral response engagement by an organism is typically constrained by the arrival time of sensory information to the brain. While psychophysical response latencies to acoustic information have been investigated, little is known about how variations in neuronal response time relate to sensory signal characteristics. Consequently, the primary objective of the present investigation was to determine the pattern of neuronal activation induced by simple (pure tones), complex (noise bursts and frequency modulated sweeps), and natural (conspecific vocalizations) acoustic signals of different durations in cat auditory cortex. Our analysis revealed three major cortical response characteristics. First, latency measures systematically increase in an antero-dorsal to postero-ventral direction among regions of auditory cortex. Second, complex acoustic stimuli reliably provoke faster neuronal response engagement than simple stimuli. Third, variations in neuronal response time induced by changes in stimulus duration are dependent on acoustic spectral features. Collectively, these results demonstrate that acoustic signals, regardless of complexity, induce a directional pattern of activation in auditory cortex.

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    • "The mean latencies of tone-evoked excitatory responses in the PU and GP neurons (23.1 and 28.2 ms) compare favorably with the auditory mean initial onset latencies reported by other investigators (Bordi and LeDoux 1992; Bordi et al. 1993; Chudler et al. 1995), but this is obviously longer than the latency seen in the cat's A1 neurons (10.9 ms; Carrasco and Lomber 2011) and medial geniculate body neurons (12–18 ms; "
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    Full-text · Article · Feb 2014 · Journal of Neurophysiology
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    • "Analysis of neural response latency has been useful in developing models of visual cortical function [29], [30]. Recently, neural latency was also used to reveal the auditory processing stream in cats [31] and primates [32]. In anesthetized rats, some previous studies reported that the mean onset latency was typically longer in PAF than in A1 [5], [7], and others reported that AAF neurons exhibit shorter response latencies than A1 neurons [13]. "
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    Full-text · Article · May 2013 · PLoS ONE
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    Full-text · Article · Jul 2012 · The Journal of Neuroscience : The Official Journal of the Society for Neuroscience
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