Purkinje Cell Simple Spike Activity Research Articles

Modulation of cerebellar cortical, cerebellar nuclear and vestibular nuclear activity using alternating electric currents.

Cerebellar transcranial alternating current stimulation (ctACS) has shown promise as a therapeutic modality for treating a variety of neurological disorders, and for affecting normal learning processes. Yet, little is known about how electric fields induced by applied currents affect cerebellar activity in the mammalian cerebellum under in vivo conditions. Alternating current (AC) stimulation with frequencies from 0.5 to 20 Hz was applied to the surface of the cerebellum in anesthetized rats. Extracellular recordings were obtained from Purkinje cells (PC), cerebellar and vestibular nuclear neurons, and other cerebellar cortical neurons. AC stimulation modulated the activity of all classes of neurons. Cerebellar and vestibular nuclear neurons most often showed increased spike activity during the negative phase of the AC stimulation. Purkinje cell simple spike activity was also increased during the negative phase at most locations, except for the cortex directly below the stimulus electrode, where activity was most often increased during the positive phase of the AC cycle. Other cortical neurons showed a more mixed, generally weaker pattern of modulation. The patterns of Purkinje cell responses suggest that AC stimulation induces a complex electrical field with changes in amplitude and orientation between local regions that may reflect the folding of the cerebellar cortex. Direct measurements of the induced electric field show that it deviates significantly from the theoretically predicted radial field for an isotropic, homogeneous medium, in both its orientation and magnitude. These results have relevance for models of the electric field induced in the cerebellum by AC stimulation.

Encoding of eye movements explains reward-related activity in cerebellar simple spikes.

The cerebellum exhibits both motor and reward-related signals. However, it remains unclear whether reward is processed independently from the motor command or might reflect the motor consequences of the reward drive. To test how reward-related signals interact with sensorimotor processing in the cerebellum, we recorded Purkinje cell simple spike activity in the cerebellar floccular complex while monkeys were engaged in smooth pursuit eye movement tasks. The color of the target signaled the size of the reward the monkeys would receive at the end of the target motion. When the tracking task presented a single target, both pursuit and neural activity were only slightly modulated by the reward size. The reward modulations in single cells were rarely large enough to be detected. These modulations were only significant in the population analysis when we averaged across many neurons. In two-target tasks where the monkey learned to select based on the size of the reward outcome, both behavior and neural activity adapted rapidly. In both the single- and two-target tasks, the size of the reward-related modulation matched the size of the effect of reward on behavior. Thus, unlike cortical activity in eye movement structures, the reward-related signals could not be dissociated from the motor command. These results suggest that reward information is integrated with the eye movement command upstream of the Purkinje cells in the floccular complex. Thus reward-related modulations of the simple spikes are akin to modulations found in motor behavior and not to the central processing of the reward value.NEW & NOTEWORTHY Disentangling sensorimotor and reward signals is only possible if these signals do not completely overlap. We recorded activity in the floccular complex of the cerebellum while monkeys performed tasks designed to separate representations of reward from those of movement. Activity modulation by reward could be accounted for by the coding of eye movement parameters, suggesting that reward information is already integrated into motor commands upstream of the floccular complex.

Climbing Fibers Control Purkinje Cell Representations of Behavior.

A crucial issue in understanding cerebellar function is the interaction between simple spike (SS) and complex spike (CS) discharge, the two fundamentally different activity modalities of Purkinje cells. Although several hypotheses have provided insights into the interaction, none fully explains or is completely consistent with the spectrum of experimental observations. Here, we show that during a pseudo-random manual tracking task in the monkey (Macaca mulatta), climbing fiber discharge dynamically controls the information present in the SS firing, triggering robust and rapid changes in the SS encoding of motor signals in 67% of Purkinje cells. The changes in encoding, tightly coupled to CS occurrences, consist of either increases or decreases in the SS sensitivity to kinematics or position errors and are not due to differences in SS firing rates or variability. Nor are the changes in sensitivity due to CS rhythmicity. In addition, the CS-coupled changes in encoding are not evoked by changes in kinematics or position errors. Instead, CS discharge most often leads alterations in behavior. Increases in SS encoding of a kinematic parameter are associated with larger changes in that parameter than are decreases in SS encoding. Increases in SS encoding of position error are followed by and scale with decreases in error. The results suggest a novel function of CSs, in which climbing fiber input dynamically controls the state of Purkinje cell SS encoding in advance of changes in behavior.SIGNIFICANCE STATEMENT Purkinje cells, the sole output of the cerebellar cortex, manifest two fundamentally different activity modalities, complex spike (CS) discharge and simple spike (SS) firing. Elucidating cerebellar function will require an understanding of the interactions, both short- and long-term, between CS and SS firing. This study shows that CSs dynamically control the information encoded in a Purkinje cell's SS activity by rapidly increasing or decreasing the SS sensitivity to kinematics and/or performance errors independent of firing rate. In many cases, the CS-coupled shift in SS encoding leads a change in behavior. These novel findings on the interaction between CS and SS firing provide for a new hypothesis in which climbing fiber input adjusts the encoding of SS information in advance of a change in behavior.

Differential Purkinje cell simple spike activity and pausing behavior related to cerebellar modules.

The massive computational capacity of the cerebellar cortex is conveyed by Purkinje cells onto cerebellar and vestibular nuclei neurons through their GABAergic, inhibitory output. This implies that pauses in Purkinje cell simple spike activity are potentially instrumental in cerebellar information processing, but their occurrence and extent are still heavily debated. The cerebellar cortex, although often treated as such, is not homogeneous. Cerebellar modules with distinct anatomical connectivity and gene expression have been described, and Purkinje cells in these modules also differ in firing rate of simple and complex spikes. In this study we systematically correlate, in awake mice, the pausing in simple spike activity of Purkinje cells recorded throughout the entire cerebellum, with their location in terms of lobule, transverse zone, and zebrin-identified cerebellar module. A subset of Purkinje cells displayed long (>500-ms) pauses, but we found that their occurrence correlated with tissue damage and lower temperature. In contrast to long pauses, short pauses (<500 ms) and the shape of the interspike interval (ISI) distributions can differ between Purkinje cells of different lobules and cerebellar modules. In fact, the ISI distributions can differ both between and within populations of Purkinje cells with the same zebrin identity, and these differences are at least in part caused by differential synaptic inputs. Our results suggest that long pauses are rare but that there are differences related to shorter intersimple spike intervals between and within specific subsets of Purkinje cells, indicating a potential further segregation in the activity of cerebellar Purkinje cells.

Cerebellar cortical output encodes temporal aspects of rhythmic licking movements and is necessary for normal licking frequency

Rodents consume water by performing stereotypic, rhythmic licking movements that are believed to be controlled by brainstem pattern-generating circuits. Previous work has shown that synchronized population activity of inferior olive neurons was phase-locked to the licking rhythm in rats, suggesting a cerebellar involvement in temporal aspects of licking behavior. However, what role the cerebellum has in licking behavior and whether licking is represented in the high-frequency simple spike output of Purkinje cells remains unknown. We recorded Purkinje cell simple and complex spike activity in awake mice during licking, and determined the behavioral consequences of loss of cerebellar function. Mouse cerebellar cortex contained a multifaceted representation of licking behavior encoded in the simple spike activities of Purkinje cells distributed across Crus I, Crus II and lobus simplex of the right cerebellar hemisphere. Lick-related Purkinje cell simple spike activity was modulated rhythmically, phase-locked to the lick rhythm, or non-rhythmically. A subpopulation of lick-related Purkinje cells differentially represented lick interval duration in their simple spike activity. Surgical removal of the cerebellum or temporary pharmacological inactivation of the cerebellar nuclei significantly slowed the licking frequency. Fluid licking was also less efficient in mice with impaired cerebellar function, indicated by a significant decline in the volume per lick fluid intake. The gross licking movement appeared unaffected. Our results suggest a cerebellar role in modulating the frequency of the central pattern-generating circuits controlling fluid licking and in the fine coordination of licking, while contributing little to the coordination of the gross licking movement.

Encoding of Movement Dynamics by Purkinje Cell Simple Spike Activity During Fast Arm Movements Under Resistive and Assistive Force Fields

It is controversial whether simple-spike activity of cerebellar Purkinje cells during arm movements encodes movement kinematics like velocity or dynamics like muscle activities. To examine this issue, we trained monkeys to flex or extend the elbow by 45 degrees in 400 ms under resistive and assistive force fields but without altering kinematics. During the task movements after training, simple-spike discharges were recorded in the intermediate part of the cerebellum in lobules V-VI, and electromyographic activity was recorded from arm muscles. Velocity profiles (kinematics) in the two force fields were almost identical to each other, whereas not only the electromyographic activities (dynamics) but also simple-spike activities in many Purkinje cells differed distinctly depending on the type of force field. Simple-spike activities encoded much larger mutual information with the type of force field than that with the residual small difference in the height of peak velocity. The difference in simple-spike activities averaged over the recorded Purkinje-cells increased approximately 40 ms before the appearance of the difference in electromyographic activities between the two force fields, suggesting that the difference of simple-spike activities could be the origin of the difference of muscle activities. Simple-spike activity of many Purkinje cells correlated with electromyographic activity with a lead of approximately 80 ms, and these neurons had little overlap with another group of neurons the simple-spike activity of which correlated with velocity profiles. These results show that simple-spike activity of at least a group of Purkinje cells in the intermediate part of cerebellar lobules V-VI encodes movement dynamics.

Developmental changes in eyeblink conditioning and simple spike activity in the cerebellar cortex

The activity of neurons in the cerebellum exhibits learning-related changes during eyeblink conditioning in adult mammals. The induction and preservation of learning-related changes in cerebellar neuronal activity in developing rats may be affected by the level of maturity in cerebellar feedback to its brainstem afferents, including the inferior olive. Developmental changes in cerebellar plasticity were examined by recording the activity of Purkinje cells in eye regions of cerebellar cortical lobule HVI (lobulus simplex) in infant rats during eyeblink conditioning. The percentage and amplitude of eyeblink conditioned responses increased as a function of age. Analyses of Purkinje cell simple spike activity revealed developmental increases in the number of units that exhibited stimulus-evoked and learning-related changes in activity. Moreover, the magnitude of these changes exhibited a substantial age-related increase. The results support the view that the emergence of learning-specific cerebellar plasticity and the ontogeny of eyeblink conditioning are influenced by developmental changes in the synaptic interactions within brainstem-cerebellum circuits.

Activity-dependent expression of calbindin in rabbit floccular Purkinje cells modulated by optokinetic stimulation

Optokinetic stimulation activates visual climbing fiber pathways that synapse upon contralateral floccular Purkinje cells. Long-term horizontal optokinetic stimulation causes a progressive decrease in gain of the optokinetic reflex and leads to the subsequent genesis of a prolonged negative optokinetic afternystagmus. Since the flocculus is involved in adaptation to optokinetic stimulation, we used the technique of differential display reverse transcription-polymerase chain reaction to explore transcriptional changes in the flocculus evoked by long-term optokinetically evoked climbing fiber discharge. Several differentially transcribed gene products were isolated and sequenced. One of these, calbindin mRNA, was expressed in relatively decreased abundance in the flocculus that received increased climbing fiber input. Decreased transcription of calbindin mRNA was confirmed by northern blots. Hybridization histochemistry was used to localize calbindin mRNA to Purkinje cells and confirmed decreased transcription of calbindin mRNA in Purkinje cells located in folium 1 of the flocculus. Western blots and immunohistochemistry localized the climbing fiber-evoked decreased expression of calbindin to Purkinje cells in folia 1 of the flocculus. The expression of four other calcium-binding proteins in the flocculus was not influenced by optokinetic stimulation. Changes in expression of calbindin could be evoked by decreases in intracellular calcium associated with climbing fiber-evoked decreases in Purkinje cell simple spike activity. The application of differential display reverse transcription-polymerase chain reaction has provided a positive screen for several molecules in addition to calbindin whose expression is affected by naturally evoked activity in a major synaptic pathway to the cerebellum. Further experiments will be required to specify the functional role of each of these molecules.

Unilateral cholinergic stimulation of the rabbit's cerebellar flocculus: asymmetric effects on optokinetic responses

In previous work, we have demonstrated an acceleration of the buildup of slow-phase velocity of optokinetic nystagmus (OKN) after bilateral floccular injection of the aselective cholinergic agonist carbachol (Tan and Collewijn 1991; Tan et al. 1992a). In the present study we investigated the effects of unilateral floccular injections of carbachol. Such unilateral injections specifically enhanced the buildup of OKN slow-phase velocity in the direction toward the injected flocculus (ipsiversive). During binocular optokinetic stimulation, this enhancement was expressed in the motion of both eyes. Acceleration of the eye contralateral to the injected flocculus increased from 1 to about 2 degrees/s2, while the acceleration of the ipsilateral eye increased from 1 to about 1.5 degrees/s2. In contrast, buildup of contraversive OKN was unchanged. No changes were found in the steady-state OKN and optokinetic afternystagmus (OKAN). Monocular optokinetic stimulation was only effective in the nasal direction, and the effects of unilateral injection of carbachol were disconjugate. Ipsiversive OKN was enhanced only in the contralateral, seeing eye, while the response of the ipsilateral, covered eye was unchanged. We hypothesize that the directionally specific effect of unilateral cholinergic floccular stimulation on OKN is due to enhancement of predominantly the excitatory phase of modulation of the Purkinje cell's simple-spike activity by carbachol, without a marked effect of carbachol on the inhibitory phase of simple-spike modulation.

Purkinje cell simple spike activity during grasping and lifting objects of different textures and weights

1. Three monkeys (2.5-3.5 kg) were trained to pinch an object between the thumb and forefinger and to lift it a vertical distance of 1.0-2.0 cm. Either the object weight (15, 65, or 115 g) or the surface texture (sand paper or polished metal) contacting the fingers could be varied. The object was equipped with a vertical position transducer, an accelerometer, and strain gauges that measured the grip force and the vertical load force. 2. In accordance with similar previously published studies on human subjects, it was found that monkeys appropriately scaled the grip forces according to the weight and coefficient of friction of the object. The grip force preceded the load force by 25 ms, and they both covaried with the changes in surface friction. 3. An analysis of electromyograms (EMGs) recorded intramuscularly from the muscles of the wrist and fingers including both flexors and extensors indicated that 26 muscles were active during pinching and lifting. Of these, 17 produced the maximum activity for the slippery surface and the greatest weight and the least activity with the roughest surface and lightest weight. 4. A total of 59 Purkinje cells and 123 unidentified units recorded from the paravermal and lateral cerebellar cortex were found to change their firing frequency during lifting the experimental object. 5. Increased discharge during the grasping and lifting was found for 56% (33/59) of the Purkinje cells and 80% (98/123) of the unidentified neurons, whereas 44% (26/59) of the Purkinje cells and 20% of the unidentified neurons decreased activity during the same period. 6. Significant modulations of the firing frequency with surface texture or object weight occurred for 59% (35/59) of the Purkinje cells and 67% (82/123) of the unidentified neurons. 7. One hundred and three Purkinje and unidentified neurons recorded in the paravermal and lateral region of the cerebellar cortex were examined for peripheral receptive fields, and of these, 43/103 (42%) responded exclusively to imposed displacements and tapping of muscles suggesting afferents originating from proprioceptors. A further 28/103 (27%) had exclusively cutaneous receptive fields on the hand that could be stimulated by brushing the skin lightly with a sable hair brush. Only six neurons demonstrated convergent cutaneous and proprioceptive receptive fields and no response to peripheral stimulation could be found for 26 neurons. No difference was found between the receptive fields of Purkinje cells and those of the unidentified neurons.(ABSTRACT TRUNCATED AT 400 WORDS)

Relationships between simultaneously recorded Purkinje cells and nuclear neurons

In decerebrate, unanesthetized cats, the activity of a Purkinje cell and a paired neuron in the interposed nuclei (subsequently referred to as a Purkinje cell-nuclear cell pair) were simultaneously recorded to compare their spontaneous discharge characteristics and responses to a peripheral input. Microstimulation techniques were used to determine if the two neurons were in related regions of the cerebellar cortex and interposed nuclei. First, the electrode used to record the interposed nuclear neuron was used to antidromically activate the Purkinje cell. Second, inhibitory responses with the appropriate time course were evoked in the interposed neurons with the Purkinje cell recording electrode. Both the spontaneous discharge of each pair as well as the cells' responses to a mechanically generated forepaw displacement were evaluated. A total of 35 Purkinje cell-nuclear cell pairs satisfying the microstimulation criteria were studied. During spontaneous activity there was no consistent relationship between the Purkinje cell simple spike activity and the nuclear neuron activity based on cross-correlation techniques. Auto-correlograms of both cells exhibited positive correlation for a brief time period. The variability of the interspike interval of the Purkinje cell discharge was greater than that for nuclear neurons, but there was no difference in the mean interspike interval for the pairs. The simple spike activity of Purkinje cells in response to sinusoidal displacements of the forepaw was weakly modulated. The modulation was limited to a small frequency range (2–7 Hz). In contrast the nuclear neurons exhibited a greater depth of modulation than Purkinje cells and responded to a wider range of frequencies (2–15 Hz). For many pairs of cells the relationship between the Purkinje cell and nuclear neuron discharge was not reciprocal. The responses of Purkinje cell-nuclear cell pairs to forepaw displacement were more often reciprocal to square wave than to sinusoidal stimuli. Using a technique which estimated the reciprocity of Purkinje cell and nuclear cell responses, 49% of the responses were reciprocal while 51% were not. These findings suggest that a nuclear neuron's discharge characteristics are not dominated by inputs from a single Purkinje cell and the firing relationship between a Purkinje cell and a related nuclear cell need not be reciprocal.

The changes in Purkinje cell simple spike activity following spontaneous climbing fiber inputs

The purpose of these experiments was to systematically examine the characteristics of the excitability change occurring after the inactivation period evoked by the climbing fiber input to Purkinje cells. Ninety-eight Purkinje cells were isolated extracellularly unanesthetized decerebrate cats. Simple spikes and complex spikes were discriminated separately. Post-stimulus time histograms were constructed from 100 consecutive trials triggered by the occurrence of spontaneous complex spikes. Seventeen Purkinje cells exhibited a reduction of simple spike discharge rate following the inactivation period. However, 14 cells showed no change in simple spike activity, and in 67 cells the discharge rate increased. These changes in excitability following a spontaneous complex spike were independent of the tonic simple spike activity of the Purkinje cell. Single traces of spike train data from Purkinje cells showed that the change in discharge rate was variable, some complex spikes being followed by an increase and others by a decrease in activity. The basis for these observations and the differences between these data and those from studies in which the climbing fiber input was evoked by electrical olivary stimulation are discussed.

Role of climbing fiber afferent input in determining responsiveness of Purkinje cells to mossy fiber inputs.

Role of climbing fiber afferent input in determining responsiveness of Purkinje cells to mossy fiber inputs.T J Ebner, and J R BloedelT J Ebner, and J R BloedelPublished Online:01 May 1981https://doi.org/10.1152/jn.1981.45.5.962MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Download PDF FiguresReferencesRelatedInformation Cited ByHeterogeneity of Purkinje cell simple spike-complex spike interactions: zebrin- and non-zebrin-related variations26 June 2017 | The Journal of Physiology, Vol. 595, No. 15Firing Dynamics of Cerebellar Purkinje CellsFernando R. Fernandez, Jordan D. T. Engbers, and Ray W. Turner1 July 2007 | Journal of Neurophysiology, Vol. 98, No. 1Climbing Fiber Discharge Regulates Cerebellar Functions by Controlling the Intrinsic Characteristics of Purkinje Cell OutputBruce E. McKay, Jordan D. T. Engbers, W. Hamish Mehaffey, Grant R. J. Gordon, Michael L. Molineux, Jaideep S. Bains, and Ray W. Turner1 April 2007 | Journal of Neurophysiology, Vol. 97, No. 4Central vestibular system: vestibular nuclei and posterior cerebellumBrain Research Bulletin, Vol. 60, No. 5-6Dynamic Modulation of Mossy Fiber System Throughput by Inferior Olive Synchrony: A Multielectrode Study of Cerebellar Cortex Activated by Motor CortexCornelius Schwarz, and John P. Welsh1 November 2001 | Journal of Neurophysiology, Vol. 86, No. 5Cerebellar Long-Term Depression: Characterization, Signal Transduction, and Functional RolesMasao Ito1 July 2001 | Physiological Reviews, Vol. 81, No. 3Chapter 19 The cerebellum as a neuronal prosthesis machineRed Nucleus Stimulation Inhibits Within the Inferior OliveK. M. Horn, T. M. Hamm, and A. R. Gibson1 December 1998 | Journal of Neurophysiology, Vol. 80, No. 6Temporal Firing Patterns of Purkinje Cells in the Cerebellar Ventral Paraflocculus During Ocular Following Responses in Monkeys II. Complex SpikesYasushi Kobayashi, Kenji Kawano, Aya Takemura, Yuka Inoue, Toshihiro Kitama, Hiroaki Gomi, and Mitsuo Kawato1 August 1998 | Journal of Neurophysiology, Vol. 80, No. 2Topography and Reciprocal Activity of Cerebellar Purkinje Cells in the Uvula-Nodulus Modulated by Vestibular StimulationH. Fushiki, and N. H. Barmack1 December 1997 | Journal of Neurophysiology, Vol. 78, No. 6The cerebellum as a predictor of neural messages—II. Role in motor control and motion sicknessNeuroscience, Vol. 56, No. 3Effects of inferior olive inactivation and lesion on the activity of medial vestibular neurons in the ratNeuroscience, Vol. 53, No. 1Corticotropin-releasing factor suppresses the afterhyperpolarization in cerebellar Purkinje neuronsNeuroscience Letters, Vol. 149, No. 1The physiological effects of peptides and serotonin on Purkinje cell activityProgress in Neurobiology, Vol. 39, No. 5Why run parallel fibers parallel? Teleostean purkinje cells as possible coincidence detectors, in a timing device subserving spatial coding of temporal differencesNeuroscience, Vol. 48, No. 2Identification of the Purkinje cell/climbing fiber zone and its target neurons responsible for eye-movement control by the cerebellar flocculusBrain Research Reviews, Vol. 16, No. 1Topographical organization of the tecto-olivo-cerebellar projection in the catNeuroscience, Vol. 41, No. 1Topographical organization of climbing fiber pathway from the superior colliculus to cerebellar vermal lobules VI–VII in the catNeuroscience, Vol. 45, No. 3Classical conditioning of the eyeblink reflex in the decerebrate-decerebellate rabbitBehavioural Brain Research, Vol. 38, No. 1Neuromodulatory effects of corticotropin releasing factor on cerebellar purkinje cells: An in vivo study in the catNeuroscience, Vol. 39, No. 1Alterations in simple spike activity and locomotor behavior associated with climbing fiber input to Purkinje cells in a decerebrate walking catNeuroscience, Vol. 25, No. 2A study of cerebellar cortical involvement in motor learning using a new avoidance conditioning paradigm involving limb movementBrain Research, Vol. 445, No. 1Changes in the responses of cerebellar nuclear neurons associated with the climbing fiber response of Purkinje cellsBrain Research, Vol. 425, No. 1Detection of tracking errors by visual climbing fiber inputs to monkey cerebellar flocculus during pursuit eye movementsNeuroscience Letters, Vol. 72, No. 2Reduction of cerebellar norepinephrine alters climbing fiber enhancement of mossy fiber input to the Purkinje cellBrain Research, Vol. 397, No. 2The responses of simultaneously recorded Purkinje cells to the perturbations of the step cycle in the walking ferret: a study using a new analytical method — the real-time postsynaptic response (RTPR)Brain Research, Vol. 365, No. 2Effects of electrical stimulation and reversible lesions of the olivocerebellar pathway on Purkinje cell activity in the flocculus of the catBrain Research, Vol. 346, No. 1Electrophysiological study of the corticonuclear projection in the cat cerebellumBrain Research, Vol. 327, No. 1-2Climbing fiber action on the responsiveness of Purkinje cells to parallel fiber inputsBrain Research, Vol. 309, No. 1Cerebellar norepinephrine depletion and impaired acquisition of specific locomotor tasks in ratsBrain Research, Vol. 296, No. 1The changes in Purkinje cell simple spike activity following spontaneous climbing fiber inputsBrain Research, Vol. 237, No. 2Climbing fibre modification of cerebellar Purkinje cell responses to parallel fibre inputsBrain Research, Vol. 237, No. 2Climbing fibre Purkinje cell twins are found More from this issue > Volume 45Issue 5May 1981Pages 962-71 https://doi.org/10.1152/jn.1981.45.5.962PubMed7241180History Published online 1 May 1981 Published in print 1 May 1981 Metrics

Long-term adaptive changes in primate vestibuloocular reflex. III. Electrophysiological observations in flocculus of normal monkeys.

Long-term adaptive changes in primate vestibuloocular reflex. III. Electrophysiological observations in flocculus of normal monkeys.

Electrogenesis of cerebellar Purkinje cell responses in cats.

Electrogenesis of cerebellar Purkinje cell responses in cats.F E Martinez, W E Crill, and T T KennedyF E Martinez, W E Crill, and T T KennedyPublished Online:01 May 1971https://doi.org/10.1152/jn.1971.34.3.348MoreSectionsPDF (1 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByPhysiology of the cerebellumSomatosensory cortical neurons with an identifiable electrophysiological signatureBrain Research, Vol. 441, No. 1-2Membrane resistivity estimated for the purkinje neuron by means of a passive computer modelNeuroscience, Vol. 14, No. 1Plateau potentials evoked by climbing-fibre stimulation are restricted to the Purkinje cell dendrites of the catNeuroscience Letters, Vol. 45, No. 2Cultured cerebellar neurons: endogenous and exogenous components of purkinje cell activity and membrane response to putative transmittersBrain Research, Vol. 263, No. 2The changes in Purkinje cell simple spike activity following spontaneous climbing fiber inputsBrain Research, Vol. 237, No. 2The olivocerebellar system. I. Delayed and slow inhibitory effects: An overlooked salient feature of cerebellar climbing fibersBrain Research, Vol. 187, No. 1A computer model of cerebellar purkinje cellsNeuroscience, Vol. 2, No. 1Climbing fiber responses of cerebellar Purkinje cells to passive movement of the cat forepawBrain Research, Vol. 106, No. 1Anatomical, physiological and biochemical studies of the cerebellum from mutant mice. I. Electrophysiological analysis of cerebellar cortical neurons in the staggerer mouseBrain Research, Vol. 98, No. 1Cerebellar afferent systems: A reviewProgress in Neurobiology, Vol. 2Cerebellar output: Properties, synthesis and usesBrain Research, Vol. 40, No. 1The role of dendritic events in the initiation of monosynaptic spikes in frog motoneuronsBrain Research, Vol. 39, No. 2Synaptic potential summation and repetitive firing mechanisms: Input-output theory for the recruitment of neurons into epileptic bursting firing patternsBrain Research, Vol. 39, No. 1 More from this issue > Volume 34Issue 3May 1971Pages 348-56 https://doi.org/10.1152/jn.1971.34.3.348PubMed5560036History Published online 1 May 1971 Published in print 1 May 1971 Metrics

Action of climbing fibers in cerebellar cortex of the cat.

Action of climbing fibers in cerebellar cortex of the cat.

Discharge of cerebellar neurons related to two maintained postures and two prompt movements. II. Purkinje cell output and input.

Discharge of cerebellar neurons related to two maintained postures and two prompt movements. II. Purkinje cell output and input.

Discharge of Purkinje and cerebellar nuclear neurons during rapidly alternating arm movements in the monkey.

Discharge of Purkinje and cerebellar nuclear neurons during rapidly alternating arm movements in the monkey.

Relation of pyramidal tract activity to force exerted during voluntary movement.

in a series P of studies of the relation of discharge 01 pyramlda1 tract neurons (PTNs) to voluntary movement. The first of the previous studies (5) showed that PTN activity both at rest and during movement is related to axonal conduction velocity. PTNs with the highest axonal conduction velocities tend to be silent during motor quiescence and to show phasic activity in association with movement. PTNs with lower axonal conduction velocities are for the most part active even in the absence of movement; with movement they show both upward and downward modulation of their resting discharge frequency. A second study (6) was carried out to obtain information as to the point in the interval between stimulus and response at which PTN discharge takes place in association with a conditioned hand movement. It was found that for many PTNs, responses to the conditioned stimulus (the onset of a light) preceded the first peripheral electromyographic correlates of the conditioned response (wrist extension). The fact that these PTN responses preceded the electromyographic response showed that they were not consequent upon feedback resulting from the movement. 1