@article{f5daf094563546769ec20c1571257604,
title = "Corticofugal modulation of the medial geniculate body",
abstract = "The function of corticothalamic projections in the auditory system was investigated by reversible inactivation of primary auditory cortex. Changes in the discharges of multiple-unit {"}clusters{"} within the ventral division of the medial geniculate body were assessed following removal of normal descending influences by cortical cooling. Patterns of neuronal discharges to clicks or tones were classified as either reverberatory or nonreverberatory during precool control sessions. Cortical cooling suppressed the late reverberatory discharges of the former, but had no effect on the discharge rate or pattern of the latter. The short-latency (< 20 msec) response was unaltered for either type. In addition, cooling of primary auditory cortex produced a significant increase in the background activity of nonreverberatory neurons but had no consistent effects on background activity of reverberatory neurons. Two distinct corticothalamic pathways are postulated to account for these results.",
author = "Ryugo, {David K.} and Weinberger, {Norman M.}",
note = "Funding Information: It is well known that sensory systems have descending pathways which apparently parallel their ascending components (12, 18, 20, 21, 24, 28, 29). The existence of reciprocal anatomic connections between neocortex and thalamus has special relevance to the concept that sensory cortex modulates its own input (14, 19). In this regard, it has been demonstrated that the various subdivisions of auditory cortex in the cat are differentially connected to distinct subdivisions of the medial geniculate body (9-12, 30, 31). In particular, there exist reciprocal connections between discrete subregions of primary auditory cortex and discrete areas within the ventral medial geniculate body which include pars lateralis and pars ovoidea (8). Despite the prominence of these corticofugal projections and the detailed anatomical accounts that are available, only few published reports have 1 This research was supported by U.S.P.H.S. Grant MH 22712 from the National Institute of Mental Health. We are pleased to acknowledge with thanks the invaluable assistance of Elaine Hackelman. Dr. Ryugo was supported by U.S.P.H.S. Predoctoral Fellowship MH 05424. Copyright: Copyright 2014 Elsevier B.V., All rights reserved.",
year = "1976",
month = may,
doi = "10.1016/0014-4886(76)90262-4",
language = "English (US)",
volume = "51",
pages = "377--391",
journal = "Experimental Neurology",
issn = "0014-4886",
publisher = "Academic Press Inc.",
number = "2",
}