The effects of stimuli on the activity and functional connectivity of local neuronal groups in the cat auditory cortex

Simultaneous extracellular recordings from one electrode of 'local' groups of 3-6 neurons were obtained from the auditory cortex of unanesthetized, paralyzed cats. The activity and functional connectivity of local microenvironments were examined under various auditory stimuli. Single cell response patterns were examined using peri-stimulus (PST) histograms and functional connectivity among neighboring cells by the cross renewal density (CRD) histograms. Analysis of the PST histograms suggested that a high percentage of single cells demonstrated different response patterns to different stimuli. Analysis of the CRD histograms suggested, on the one hand, that only small numbers of neighboring cells behaved as if there were direct connections from one cell to another, and that these direct connections appeared to be excitatory. On the other hand, many cell pairs shared input from shared sources which lay outside the local groups. The majority of functional connections were altered by at least one of the stimuli delivered, thus demonstrating the system's plasticity. It is suggested that long-term gates at the synaptic level are responsible for this phenomenon.

[1]  Moshe Abeles,et al.  Single Unit Activity of the Auditory Cortex , 1975 .

[2]  S. Erulkar.  Physiological Studies of the Inferior Colliculus and Medial Geniculate Complex , 1975 .

[3]  K. Tanaka,et al.  Cross-Correlation Analysis of Interneuronal Connectivity in cat visual cortex. , 1981, Journal of neurophysiology.

[4]  A. C. Webb,et al.  The correlation between discharge times of neighbouring neurons in isolated cerebral cortex , 1979, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[5]  H. L. Bryant,et al.  Correlations of neuronal spike discharges produced by monosynaptic connections and by common inputs. , 1973, Journal of neurophysiology.

[6]  H L Wood,et al.  Distributed processing by visual interneurons of crayfish brain. II. Network organization and stimulus modulation of synaptic efficacy. , 1980, Journal of neurophysiology.

[7]  J. Houchin,et al.  Units in the cerebral cortex of the anaesthetized rat and the correlations between their discharges , 1966, The Journal of physiology.

[8]  G. Gerstein,et al.  Interactions between cat lateral geniculate neurons. , 1976, Journal of neurophysiology.

[9]  M. Abeles.  Local Cortical Circuits: An Electrophysiological Study , 1982 .

[10]  M. Abeles,et al.  Multispike train analysis , 1977, Proceedings of the IEEE.

[11]  G. P. Moore,et al.  Statistical signs of synaptic interaction in neurons. , 1970, Biophysical journal.

[12]  Cross-correlation analysis of connectivities among cat lumbosacral dorsal horn cells. , 1979, Journal of neurophysiology.

[13]  W. R. Adey,et al.  Firing of neuron pairs in cat association cortex during sleep and wakefulness. , 1970, Journal of neurophysiology.

[14]  G L Gerstein,et al.  Interactions between neurons in auditory cortex of the cat. , 1974, Journal of neurophysiology.

[15]  W. R. Adey,et al.  Neuronal activity in the association cortex of the cat during sleep, wakefulness and anesthesia. , 1973, Brain research.

[16]  M. Goldstein,et al.  Single-unit activity in the primary auditory cortex of unanesthetized cats. , 1968, The Journal of the Acoustical Society of America.

[17]  J. Kelly,et al.  Identification of possible inhibitory neurons in the pericruciate cortex of the cat. , 1974, Brain research.

[18]  G. P. Moore,et al.  Neuronal spike trains and stochastic point processes. II. Simultaneous spike trains. , 1967, Biophysical journal.

[19]  G. P. Moore,et al.  Neuronal spike trains and stochastic point processes. I. The single spike train. , 1967, Biophysical journal.

[20]  P. Kirkwood.  On the use and interpretation of cross-correlation measurements in the mammalian central nervous system , 1979, Journal of Neuroscience Methods.

[21]  G L Gerstein,et al.  Mutual temporal relationships among neuronal spike trains. Statistical techniques for display and analysis. , 1972, Biophysical journal.

[22]  M. Sanders.  Handbook of Sensory Physiology , 1975 .

[23]  M. Abeles,et al.  Functional architecture in cat primary auditory cortex: columnar organization and organization according to depth. , 1970, Journal of neurophysiology.

[24]  M. Abeles.  Quantification, smoothing, and confidence limits for single-units' histograms , 1982, Journal of Neuroscience Methods.