Control of Spatiotemporal Coherence of a Thalamic Oscillation by Corticothalamic Feedback

The mammalian thalamus is the gateway to the cortex for most sensory modalities. Nearly all thalamic nuclei also receive massive feedback projections from the cortical region to which they project. In this study, the spatiotemporal properties of synchronized thalamic spindle oscillations (7 to 14 hertz) were investigated in barbiturate-anesthetized cats, before and after removal of the cortex. After complete ipsilateral decortication, the long-range synchronization of thalamic spindles in the intact cortex hemisphere changed into disorganized patterns with low spatiotemporal coherence. Local thalamic synchrony was still present, as demonstrated by dual intracellular recordings from nearby neurons. In the cortex, synchrony was insensitive to the disruption of horizontal intracortical connections. These results indicate that the global coherence of thalamic oscillations is determined by corticothalamic projections.

[1]  R. Morison,et al.  MECHANISM OF THALAMOCORTICAL AUGMENTATION AND REPETITION , 1943 .

[2]  R. Morison,et al.  ELECTRICAL ACTIVITY OF THE THALAMUS AND BASAL GANGLIA IN DECORTICATE CATS , 1945 .

[3]  S. Andersson,et al.  Physiological basis of the alpha rhythm , 1968 .

[4]  M. Yahr,et al.  Corticothalamic projections and sensorimotor activities , 1972 .

[5]  M Steriade,et al.  Thalamic projections of nucleus reticularis thalami of cat: A study using retrograde transport of horseradish peroxidase and fluorescent tracers , 1984, The Journal of comparative neurology.

[6]  Problems Plague ASAT Program. , 1985, Science.

[7]  C. Koch,et al.  The action of the corticofugal pathway on sensory thalamic nuclei: A hypothesis , 1987, Neuroscience.

[8]  W. Press,et al.  Numerical Recipes: The Art of Scientific Computing , 1987 .

[9]  C. Avendaño,et al.  Organization of the association cortical afferent connections of area 5: A retrograde tracer study in the cat , 1988, The Journal of comparative neurology.

[10]  E. G. Jones,et al.  Thalamic oscillations and signaling , 1990 .

[11]  D. McCormick,et al.  Mechanisms of oscillatory activity in guinea‐pig nucleus reticularis thalami in vitro: a mammalian pacemaker. , 1993, The Journal of physiology.

[12]  D. McCormick,et al.  Cellular mechanisms of a synchronized oscillation in the thalamus. , 1993, Science.

[13]  D J Woodward,et al.  Dynamic and distributed properties of many-neuron ensembles in the ventral posterior medial thalamus of awake rats. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[14]  T. Sejnowski,et al.  Modeling the control of reticular thalamic oscillations by neuromodulators. , 1994, Neuroreport.

[15]  D. Contreras,et al.  Cellular basis of EEG slow rhythms: a study of dynamic corticothalamic relationships , 1995, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[16]  D. McCormick,et al.  Synaptic and membrane mechanisms underlying synchronized oscillations in the ferret lateral geniculate nucleus in vitro. , 1995, The Journal of physiology.

[17]  T. Sejnowski,et al.  Ionic mechanisms underlying synchronized oscillations and propagating waves in a model of ferret thalamic slices. , 1996, Journal of neurophysiology.

[18]  D. Contreras,et al.  Spindle oscillation in cats: the role of corticothalamic feedback in a thalamically generated rhythm. , 1996, The Journal of physiology.