Summary
Seventy seven thalamic neurons in the VA-VL nuclear complex of the cat which projected to the anterior sigmoid gyrus (ASG) were studied extracellularly, and their responses to stimulation of both the cerebellar nuclei (CN) and the entopeduncular nucleus (ENT) were examined. Forty two neurons were inhibited by ENT-stimulation but were not excited by CN-stimulation, while 27 neurons were excited by CN-stimulation but were not inhibited by ENT-stimulation. Eight neurons were inhibited by ENT-stimulation and also excited by CN-stimulation. Distribution of axons in each layer of ASG was examined by means of antidromic activation of the thalamic neurons by microstimulation at various depths of ASG. Almost all (13/14) of the ENT-inhibited neurons examined were antidromically activated by microstimulation in layer I with currents less than 35 μA. On the other hand, most (11/13) of CN-excited neurons were antidromically activated by weak microstimulation in layers deeper than the second, but were not activated by microstimulation in layer I with currents less than 40 μA. VA-VL neurons with inhibitory input from ENT were considered to project mainly to layer I of ASG.
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References
Anderson FD, Berry CM (1959) Degeneration studies of long ascending fiber systems in cat brain stem. J Comp Neurol 111: 195–229
Asanuma H, Fernandez J, Scheibel ME, Scheibel AB (1974) Characteristics of projection from the nucleus ventralis lateralis to the motor cortex in the cat. Exp Brain Res 20: 315–330
Berkley KJ (1983) Spatial relationships between the terminations of somatic sensory motor pathways in the rostral brainstem of cats and monkeys. II. Cerebellar projections compared with those of the ascending somatic sensory pathways in lateral diencephalon. J Comp Neurol 220: 229–251
Dieckmann G, Sasaki K (1970) Recruiting responses in the cerebral cortex produced by putamen and pallidum stimulation. Exp Brain Res 10: 236–250
Filion M, Harnois C (1978) A comparison of projections of entopeduncular neurons to the thalamus, the midbrain and the habenula in the cat. J Comp Neurol 181: 763–780
Hassler R, Muhs-Clement K (1964) Architektonischer Aufbau des sensorimotorischen und parietalen Cortex der Katze. J Hirnforsch 6: 377–420
Jones EG (1975) Lamination and distribution of thalamic afferents within the sensory motor cortex of the squirrel monkey. J Comp Neurol 160: 167–204
Kuo JS, Carpenter MB (1973) Organization of pallidothalamic projection in rhesus monkey. J Comp Neurol 151: 201–236
Larsen KD, McBride RL (1979) The organization of the feline entopeduncular nucleus projection: anatomical studies. J Comp Neurol 184: 293–308
Maciewicz R, Phipps BS, Bry J, Highstein SM (1982) The vestibulothalamic pathway: contribution of the ascending tract of Deiters. Brain Res 252: 1–11
Oka H, Ito J, Kawamura M (1982) Identification of thalamocortical neurons responsible for cortical recruiting and spindle activities in cats. Neurosci Lett 33: 13–18
Raymond J, Sans A, Marty R (1974) Projections thalamique des noyaux vestibulaires. Etude histologique chez le chat. Exp Brain Res 20: 273–293
Sasaki K, Kawaguchi S, Matsuda Y, Mizuno N (1972) Electrophysiological studies on the cerebello-cerebral projections in the cat. Exp Brain Res 16: 75–88
Sasaki K, Staunton HP, Dieckmann G (1970) Characteristic features of augmenting and recruiting responses in the cerebral cortex. Exp Neurol 26: 393–400
Schell GR, Strick PL (1984) The origin of thalamic inputs to the arcuate premotor and supplementary motor areas. J Neurosci 4: 539–560
Shinoda Y, Futami T, Kano M (1985) Synaptic organization of the cerebello-thalamo-cerebral pathway in the cat. II. Input-output organization of single thalamocortical neurons in the ventrolateral thalamus. Neurosci Res 2: 157–180
Strick PL, Sterling P (1974) Synaptic termination of afferents from the ventrolateral nucleus of the thalamus in the cat motor cortex. J Comp Neurol 153: 77–106
Uno M, Ozawa N, Yoshida M (1978) The mode of pallidothalamic transmission investigated with intracellular recording from cat thalamus. Exp Brain Res 33: 493–507
Yamamoto T, Noda T, Miyata M, Nishimura Y (1984) Electrophysiological and morphological studies on thalamic neurons receiving entopedunculo- and cerebello-thalamic projections in the cat. Brain Res 301: 231–242
Yoshida M, Yajima K, Uno M (1966) Different activation of the two types of the pyramidal tract neurons through the cerebellothalamo-cortical pathways. Experientia 22: 331–332
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Jinnai, K., Nambu, A. & Yoshida, S. Thalamic afferents to layer I of anterior sigmoid cortex originating from the VA-VL neurons with entopeduncular input. Exp Brain Res 69, 67–76 (1987). https://doi.org/10.1007/BF00247030
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DOI: https://doi.org/10.1007/BF00247030