Summary
Unrestrained cats performed ballistic forelimb flexion movements triggered by an auditory stimulus (CS) on a simple reaction time (RT) paradigm. During the variable foreperiod the subject was required to hold down a lever and to release it on presentation of the CS. The RTs ranged from 200 to 300 ms. The activity of single neurons of the ventrolateral nucleus of the thalamus (VL) was recorded bilaterally.
More than 40% of the 166 units recorded in the VL contralateral to the performing limb presented, after the CS, changes of activity with a latency less than 100 ms and were classified into three types:
-
(1)
Twenty-five units had a short latency transient increase of activity 10 to 30 ms after the CS, followed by a longer increase or decrease in activity. Short latency increase as well as subsequent increase of the firing rate were not correlated to the RTs.
-
(2)
Twenty-nine units showed a 40–60 ms latency increase of activity which lasted long enough to continue during the forelimb movement. These units displayed a correlation between the RTs and the mean firing rate measured in the 40–100 ms period after the CS. The more the cells were activated, the shorter the RTs.
-
(3)
Fifteen units presented a reciprocal pattern of discharge with respect to the type (2) units. The firing rate decreased with latencies ranging from 20 to 90 ms after the CS.
Only 14,5% of the 96 units recorded in the VL ipsilateral to the performing limb presented changes of activity starting in the 100 ms period following the CS. Background firing levels as well as phasic activity were rather low compared to those observed contralaterally. Sixteen units showed burst activity while the cat was performing but burst pattern was not time-related to the task.
In an unconditioned animal, a very low level of activity and an absence of modulations were observed in both VLs.
Similar content being viewed by others
References
Allen, G.I., Tsukahara, N.: Cerebrocerebellar communication systems. Physiol. Rev. 54, 957–1006 (1974)
Amassian, V.E., Ross, R., Wertenbaker, C., Weiner, H.: Cerebello-thalamo-cortical interrelations in contact placing and other movements in cats. In: T.L. Frigyesi, E. Rinvik, M.D. Yahr (eds.): Corticothalamic projections and sensorimotor activities, pp. 395–440. New York: Raven Press 1972
Beaton, R., Miller, J.M.: Single cell activity in the auditory cortex of the unanesthetized, behaving monkey: correlation with stimulus controlled behavior. Brain Res. 100, 543–562 (1975)
Bénita, M., Condé, H., Dormont, J.F., Schmied, A.: Effects of cooling the thalamic ventrolateral nucleus of cats on a reaction time task. Exp. Brain Res. 34, 435–452 (1979)
Blair-Thomas, C.A., Luschei, E.S.: Increase in reflex excitability of monkey masseter motoneurons before a jaw-bite reaction-time response. J. Neurophysiol. 38, 981–989 (1975)
Brooks, V.B., Stoney, S.D. Jr.: Motor mechanisms: the role of the pyramidal system in motor control. Ann. Rev. Physiol. 33, 337–392 (1971)
Condé, H., Dormont, J.F., Schmied, A., Bénita, M.: Scheduled training of cats to a simple reaction time performance. J. Physiol. (Paris) 74, 439–446 (1978)
Crowell, R.M., Perret, E., Siegfried, J., Villoz, J.P.: Movement units and tremor phasic units in the human thalamus. Brain Res. 11, 481–488 (1968)
Dormont, J.F.: Patterns of spontaneous unit activity in the ventrolateral thalamic nucleus of cats. Brain Res. 37, 223–239 (1972)
Engel, J. Jr.: Intracellular study of auditory evoked activity in pericruciate cortex of the awake, non-paralyzed cat. Brain Res. 85, 69–73 (1975)
Evarts, E.V.: Pyramidal tract activity associated with a conditioned hand movement in the monkey. J. Neurophysiol. 29, 1011–1027 (1966)
Evarts, E.V.: Activity of thalamic and cortical neurons in relation to learned movement in the monkey. Intern. J. Neurol. 8, 321–326 (1971a)
Evarts, E.V.: Feed-back and corollary discharge: a merging of the concepts. In: Central Control of Movement, Neuroscience Res. Progr. Bull. 9, 86–112 (1971b)
Evarts, E.V.: Precentral and postcentral cortical activity in association with visually triggered movement. J. Neurophysiol. 37, 373–381 (1974)
Evarts, E.V., Tanji, J.: Reflex and intended responses in motor cortex pyramidal tract neurons of monkey. J. Neurophysiol. 39, 1069–1080 (1976)
Evarts, E.V., Thach, W.T.: Motor mechanisms of the CNS: cerebrocerebellar interrelations. Ann. Rev. Physiol. 31, 451–498 (1969)
Jasper, H.H., Bertrand, G.: Thalamic units involved in somatic sensation and voluntary and involuntary movements in man. In: The thalamus, D.P. Purpura, M.D. Yahr (eds.), pp. 365–389. New York: Columbia University Press 1966
Joffroy, A.J., Lamarre, Y.: Single cell activity in the ventral lateral thalamus of the unanesthetized monkey. Exp. Neurol. 42, 1–16 (1974)
Luschei, E., Saslow, C., Glickstein, M.: Muscle potentials in reaction time. Exp. Neurol. 18, 429–442 (1967)
Luschei, E.S., Garthwaite, C.R., Armstrong, M.E.: Relationship of firing patterns of units in face area of monkey precentral cortex to conditioned jaw movements. J. Neurophysiol. 34, 552–561 (1971)
Massion, J.: Intervention des voies cérébello-corticales et cortico-cérébelleuses dans l'organisation et la régulation du mouvement. J. Physiol. (Paris) 67, 117A-170A (1973)
Mortimer, J.A.: Cerebellar responses to teleceptive stimuli in alert monkeys. Brain Res. 83, 369–390 (1975)
Porter, R., Lewis, M., McD: Relationship of neuronal discharges in the precentral gyrus of monkeys to the performance of arm movements. Brain Res. 98, 21–36 (1975)
Rispal-Padel, L., Gangretto, A.: The cerebello-thalamo-cortical pathway. Topographical investigation at the unitary level in the cat. Exp. Brain Res. 28, 101–123 (1977)
Schmied, A., Bénita, M., Condé, H., Dormont, J.F.: Corrélations entre l'activité des cellules du noyau ventrolatéral et les temps de réaction chez le chat conditionné. J. Physiol. (Paris) 69, 296A-297A (1974)
Smith, A.M., Massion, J., Gahery, Y., Roumieu, J.: Unitary activity of ventrolateral nucleus during placing movement and associated postural adjustment. Brain Res. 149, 329–346 (1978)
Strick, P.L.: Anatomical analysis of ventrolateral thalamic input to primate motor cortex. J. Neurophysiol. 39, 1020–1031 (1976a)
Strick, P.L.: Activity of ventrolateral thalamic neurons during arm movement. J. Neurophysiol. 39, 1032–1044 (1976b)
Thach, W.T.: Discharge of cerebellar neurons related to two maintained postures and two prompt movements. I. Nuclear cell output. J. Neurophysiol. 33, 527–536 (1970)
Thach, W.T.: Timing of activity in cerebellar dentate nucleus and cerebral motor cortex during prompt volitional movement. Brain Res. 88, 233–241 (1975)
Vilis, T., Hore, J., Meyer-Lohmann, J., Brooks, V.B.: Dual nature of the precentral response to limb perturbations revealed by cerebellar cooling. Brain Res. 117, 336–340 (1976)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Schmied, A., Bénita, M., Condé, H. et al. Activity of ventrolateral thalamic neurons in relation to a simple reaction time task in the cat. Exp Brain Res 36, 285–300 (1979). https://doi.org/10.1007/BF00238912
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00238912