Cerebellar Participation Research Articles

Sensitivity of Cerebellar Reaching Ataxia to Kinematic and Dynamic Demands.

Individuals with cerebellar ataxia often face significant challenges in controlling reaching, especially when multijoint movements are involved. This study investigated the effects of kinematic and dynamic demands on reaching movements by individuals with cerebellar ataxia and healthy controls using a virtual reality task. Participants reached to target locations designed to elicit a range of coordination strategies between shoulder and elbow joint movements. Results showed that the cerebellar group exhibited greater trajectory curvature and variability in hand paths compared to controls, with pronounced deficits in the initial hand movement direction. Kinematic simulations indicated that early hand movement errors were sensitive to the required onset times and rates of joint movements and were most impaired when opposite direction joint movements were required (e.g., elbow extension with shoulder flexion). This highlights significant disruptions in motion planning and feedforward control in the cerebellar group. Dynamic analysis showed that cerebellar participants' movements were more impaired in reaching directions where interaction torques normally assist the desired elbow and shoulder movements, which required them to rely more on muscle torques to move. These reach directions were also those that required opposite direction joint movements. Overall, our data suggest that reaching deficits in cerebellar ataxia result from 1) the early-phase motion planning deficits that worsen with tight timing requirements and 2) the inability to compensate for interaction torques, particularly when they assist the intended movement.

The cerebellum monitors errors and entrains executive networks

Frontal midline θ (Fmθ) activity occurs in medial prefrontal cortices (mPFC), when expected and actual outcomes conflict. Cerebellar forward models could inform the mPFC about this mismatch.To verify this hypothesis we correlated the mPFC activation during a visuomotor tracking task (VM) with performance accuracy, in control and cerebellum-lesioned participants. Additionally, purely visual (V), motor (M) and a motor plus visual tasks (V + M) were performed.An Independent Component, with a mid-frontal topography scalp map and equivalent dipole location in the dorsal anterior cingulate cortex accounted for Fmθ.In control participants Fmθ power increased during VM, when the error level crossed a threshold, but not during V + M, M and V. This increase scaled with tracking error.Fmθ power failed to increase during VM in cerebellar participants, even at highest tracking errors.Thus, in control participants, activation of mPFC is induced when a continuous monitoring effort for online error detection is required. The presence of a threshold error for enhancing Fmθ, suggests the switch from an automatic to an executive tracking control, which recruits the mPFC.Given that the cerebellum stores forward models, the absence of Fmθ increases during tracking errors in cerebellar participants indicates that cerebellum is necessary for supplying the mPFC with prediction error-related information. This occurs when automatic control falters, and a deliberate correction mechanism needs to be triggered.Further studies are needed to verify if this alerting function also occurs in the context of the other cognitive and non-cognitive functions in which the cerebellum is involved.

Structural and functional changes of the cerebellum in temporal lobe epilepsy.

This study aimed to comprehensively explore the cerebellar structural and functional changes in temporal lobe epilepsy (TLE) and its association with clinical information. The SUIT toolbox was utilized to perform cerebellar volume and diffusion analysis. In addition, we extracted the average diffusion values of cerebellar peduncle tracts to investigate microstructure alterations. Seed-based whole-brain analysis was used to investigate cerebellar-cerebral functional connectivity (FC). Subgroup analyses were performed to identify the cerebellar participation in TLE with/without hippocampal sclerosis (HS)/focal-to-bilateral tonic-clonic seizure (FBTCS) and TLE with different lateralization. TLE showed widespread gray matter atrophy in bilateral crusII, VIIb, VIIIb, left crusI, and left VIIIa. Both voxel and tract analysis observed diffusion abnormalities in cerebellar afferent peduncles. Reduced FC between the right crus II and the left parahippocampal cortex was found in TLE. Additionally, TLE showed increased FCs between left lobules VI-VIII and cortical nodes of the dorsal attention and visual networks. Across all patients, decreased FC was associated with poorer cognitive function, while increased FCs appeared to reflect compensatory effects. The cerebellar structural changes were mainly observed in HS and FBTCS subgroups and were regardless of seizure lateralization, while cerebellar-cerebral FC alterations were similar in all subgroups. TLE exhibited microstructural changes in the cerebellum, mainly related to HS and FBTCS. In addition, altered cerebellar-cerebral functional connectivity is associated with common cognitive alterations in TLE.

Head Orientation Modulates Vestibular Cerebellar Evoked Potentials (VsCEPs) and Reflexes Produced by Impulsive Mastoid and Midline Skull Stimulation

The cerebellum plays a critical role in the modulation of vestibular reflexes, dependent on input from proprioceptive afferents. The mechanism of this cerebellar control is not well understood. In a sample of 11 healthy human subjects, we investigated the effects of head orientation on ocular, cervical, postural and cerebellar short latency potentials evoked by impulsive stimuli applied at both mastoids and midline skull sites. Subjects were instructed to lean backwards with the head positioned straight ahead or held rotated in different degrees of yaw towards the right and left sides. Impulsive mastoid stimulation, a potent method of utricular stimulation, produced localised vestibular cerebellar evoked potentials (VsCEPs: P12-N17) which were strongly modulated by head orientation. The response was larger on the side opposite to the direction of head rotation and with stimulation on the side of rotation. In contrast, ocular VEMPs (oVEMPs: n10-p16) were present but showed little change with head posture, while cervical VEMPs (cVEMPs: p15-n23) were larger with the head held rotated away from the side of the recording. Postural effects with lateral vestibular stimulation were strongly modulated by head rotation, with more powerful effects occurring bilaterally with stimulation on the side of rotation. The duration of the postural EMG changes was similar to the post-excitation inhibition of the electrocerebellogram (ECeG), consistent with cerebellar participation. We conclude that head rotation selectively affects evoked vestibular reflexes towards different targets, consistent with their physiological roles. Changes in VsCEPs may contribute to the modulation of postural reflexes by the cerebellum.

The Neurophysiology of the Cerebellum in Emotion.

Neuroscientific investigation of the detailed neurophysiology of emotion processing is a rapidly progressing field, which has opened discussion on key findings regarding the timing characteristics of the neuronal networks involved. Study designs incorporating quantitative electroencephalography (EEG) and event-related potentials (ERP) have mapped neuronal representations at various stages of emotion processing, identifying early and late stages corresponding to cerebral activity in attention and in appraisal of emotion. Interestingly, in addition to confirming aspects of cerebral cortex involvement, these investigations have also implicated the cerebellum in emotion processing. This has led to research aimed at distinguishing the contributions of cerebellar and cerebral networks and how these may interrelate. With respect to underlying neurophysiological mechanisms, ERP studies confirm that the cerebellum is involved in both early and late stages of processing of salient emotion cues, and also in capturing emotions in facial expressions. Topological analyses indicate direct connections between the vermis, Crus I, and Crus II areas of the cerebellum and the cerebral area of lateral prefrontal cortex. This suggests a broad evolutionary development of large-scale cerebral networks in emotion. In this chapter, we highlight findings to date of neurophysiological activity related to cerebellar participation in emotion processing. The neurophysiological findings, which by inference represent underlying neural activity, emphasize an integrative role of the cerebellum in emotion.

Cerebellar Theta and Beta Noninvasive Stimulation Rhythms Differentially Influence Episodic Memory versus Semantic Prediction.

The human cerebellum is thought to interact with distributed brain networks to support cognitive abilities such as episodic memory and semantic prediction. Hippocampal and fronto-temporo-parietal networks that respectively support episodic memory versus semantic prediction have been associated with distinct endogenous oscillatory activity frequency bands: theta (∼3-8 Hz) versus beta (∼13-30 Hz) respectively. We sought to test whether it is possible to toggle cerebellar participation in episodic memory versus semantic prediction by noninvasively stimulating with theta versus beta rhythmic transcranial magnetic stimulation. In human subjects of both sexes, cerebellar theta stimulation improved episodic memory encoding but did not influence neural signals of semantic prediction, whereas beta stimulation of the same cerebellar location increased neural signals of semantic prediction but did not influence episodic memory encoding. This constitutes evidence for double dissociation of cerebellar contributions to semantic prediction versus episodic memory based on stimulation rhythm, supporting the hypothesis that the cerebellum can be biased to support these distinct cognitive abilities at the command of network-specific rhythmic activity.SIGNIFICANCE STATEMENT The cerebellum interacts with several distinct large-scale brain networks for cognitive function, but the factors governing selectivity of such interactions for particular functions are not fully understood. We tested the hypothesis that cerebellar contributions to cognition are guided by neural oscillations with function-specific frequency bands. We demonstrated that matching noninvasive stimulation to network-specific frequencies selectively enhanced episodic memory versus semantic prediction. These findings suggest that cerebellar contributions to cognitive networks are selected based on corresponding activity rhythms and could be used to develop cerebellar stimulation interventions for specific neurocognitive impairments.

Motor Performance But Neither Motor Learning Nor Motor Consolidation Are Impaired in Chronic Cerebellar Stroke Patients

The capacity to acquire and retain new motor skills is essential for everyday behavior and a prerequisite to regain functional independence following impairments of motor function caused by brain damage, e.g., ischemic stroke. Learning a new motor skill requires repeated skill practice and passes through different online and offline learning stages that are mediated by specific dynamic interactions between distributed brain regions including the cerebellum. Motor sequence learning is an extensively studied paradigm of motor skill learning, yet the role of the cerebellum during online and offline stages remains controversial. Here, we studied patients with chronic cerebellar stroke and healthy control participants to further elucidate the role of the cerebellum during acquisition and consolidation of sequential motor skills. Motor learning was assessed by an ecologically valid explicit sequential finger tapping paradigm and retested after an interval of 8 h to assess consolidation. Compared to healthy controls, chronic cerebellar stroke patients displayed significantly lower motor sequence performance independent of whether the ipsilesional or contralesional hand was used for task execution. However, the ability to improve performance during training (i.e., online learning) and to consolidate training-induced skill formation was similar in patients and controls. Findings point to an essential role of the cerebellum in motor sequence production that cannot be compensated, while its role in online and offline motor sequence learning seems to be either negligible or amenable to compensatory mechanisms. This further suggests that residual functional impairments caused by cerebellar stroke may be mitigated even months later by additional skill training.

Aberrant connections between climbing fibres and Purkinje cells induce alterations in the timing of an instrumental response in the rat.

Cerebellar participation in timing and sensory-motor sequences has been supported by several experimental and clinical studies. A relevant role of the cerebellum in timing of conditioned responses in the range of milliseconds has been demonstrated, but less is known regarding the role of the cerebellum in supra-second timing of operant responses. A dissociated role of the cerebellum and striatum in timing in the millisecond and second range had been reported, respectively. The climbing fibre-Purkinje cell synapse is crucial in timing models; thus, the aberrant connection between these cellular elements is a suitable model for evaluating the contribution of the cerebellum in timing in the supra-second range. The aberrant connection between climbing fibres and Purkinje cells was induced by administration of the antagonist of NMDA receptors MK-801 to Sprague-Dawley rats at postnatal days 7-14. The timing of an operant response with two fixed intervals (5 and 8s) and egocentric sequential learning was evaluated in 60-day-old adult rats. The aberrant connections caused a reduced accuracy in the timing of the instrumental response that was more evident in the 8-s interval and a reduced number of successive correct responses (responses emitted in the correct second without any other response between them) in the 8-s interval. In addition, an inability to incorporate new information in a sequence previously learned in egocentric-based sequence learning was apparent in rats with aberrant CF-PC synapses. These results support a relevant role for the cerebellum in the fine-tuning of the timing of operant responses in the supra-second range.

Functional Evidence for a Cerebellar Node of the Dorsal Attention Network.

The "dorsal attention network" or "frontoparietal network" refers to a network of cortical regions that support sustained attention and working memory. Recent work has demonstrated that cortical nodes of the dorsal attention network possess intrinsic functional connections with a region in ventral cerebellum, in the vicinity of lobules VII/VIII. Here, we performed a series of task-based and resting-state fMRI experiments to investigate cerebellar participation in the dorsal attention network in humans. We observed that visual working memory and visual attention tasks robustly recruit cerebellar lobules VIIb and VIIIa, in addition to canonical cortical dorsal attention network regions. Across the cerebellum, resting-state functional connectivity with the cortical dorsal attention network strongly predicted the level of activation produced by attention and working memory tasks. Critically, cerebellar voxels that were most strongly connected with the dorsal attention network selectively exhibited load-dependent activity, a hallmark of the neural structures that support visual working memory. Finally, we examined intrinsic functional connectivity between task-responsive portions of cerebellar lobules VIIb/VIIIa and cortex. Cerebellum-to-cortex functional connectivity strongly predicted the pattern of cortical activation during task performance. Moreover, resting-state connectivity patterns revealed that cerebellar lobules VIIb/VIIIa group with cortical nodes of the dorsal attention network. This evidence leads us to conclude that the conceptualization of the dorsal attention network should be expanded to include cerebellar lobules VIIb/VIIIa. The functional participation of cerebellar structures in nonmotor cortical networks remains poorly understood and is highly understudied, despite the fact that the cerebellum possesses many more neurons than the cerebral cortex. Although visual attention paradigms have been reported to activate cerebellum, many researchers have largely dismissed the possibility of a cerebellar contribution to attention in favor of a motor explanation, namely, eye movements. The present study demonstrates that a cerebellar subdivision (mainly lobules VIIb/VIIIa), which exhibits strong intrinsic functional connectivity with the cortical dorsal attention network, also closely mirrors a myriad of cortical dorsal attention network responses to visual attention and working memory tasks. This evidence strongly supports a reconceptualization of the dorsal attention network to include cerebellar lobules VIIb/VIIIa.

The role of the cerebellum in auditory processing using the SSI test

AbstractThe Synthetic Sentence Identification (SSI) test assesses central auditory pathways by measuring auditory and visual sensitivity and testing selective attention. Cerebellum activation in auditory attention and sensorial activity modulation have already been described. Assessing patients with cerebellar lesions alone using the SSI test can confirm the role of the cerebellum in auditory processing. AimTo evaluate the role of the cerebellum in auditory processing in individuals with normal hearing and in those with chronic cerebellum lesions, using the SSI test. Materials and MethodsCross-sectional cohort study. A study group comprising 18 patients with chronic cerebellar lesion and a control group of 20 healthy individuals were assessed. The SSI test was applied in an Ipsilateral Competitive Message (ICM) and Contralateral Competitive Message (CCM) modes. To compare the results between groups, we used the chi-square test for qualitative variables. ResultsA statistically significant difference was found between the study and control groups using the ICM mode of the SSI test (p=0.035), but not in the CCM mode (p=0.083). ConclusionThe results on the SSI confirmed cerebellar participation in auditory processing in individuals with chronic cerebellar lesions and in those with normal hearing assessed in this study.

Cerebro-cerebellar Resting-State Functional Connectivity in Children and Adolescents with Autism Spectrum Disorder

BackgroundThe cerebellum plays important roles in sensori-motor and supramodal cognitive functions. Cellular, volumetric, and functional abnormalities of the cerebellum have been found in autism spectrum disorders (ASD), but no comprehensive investigation of cerebro-cerebellar connectivity in ASD is available. MethodsWe used resting-state functional connectivity magnetic resonance imaging in 56 children and adolescents (28 subjects with ASD, 28 typically developing subjects) 8–17 years old. Partial and total correlation analyses were performed for unilateral regions of interest (ROIs), distinguished in two broad domains as sensori-motor (premotor/primary motor, somatosensory, superior temporal, and occipital) and supramodal (prefrontal, posterior parietal, and inferior and middle temporal). ResultsThere were three main findings: 1) Total correlation analyses showed predominant cerebro-cerebellar functional overconnectivity in the ASD group; 2) partial correlation analyses that emphasized domain specificity (sensori-motor vs. supramodal) indicated a pattern of robustly increased connectivity in the ASD group (compared with the typically developing group) for sensori-motor ROIs but predominantly reduced connectivity for supramodal ROIs; and 3) this atypical pattern of connectivity was supported by significantly increased noncanonical connections (between sensori-motor cerebral and supramodal cerebellar ROIs and vice versa) in the ASD group. ConclusionsOur findings indicate that sensori-motor intrinsic functional connectivity is atypically increased in ASD, at the expense of connectivity supporting cerebellar participation in supramodal cognition.

Cerebellum engages in automation of verb-generation skill.

Numerous studies have shown cerebellar involvement in item-specific association, a form of explicit learning. However, very few have demonstrated cerebellar participation in automation of non-motor cognitive tasks. Applying fMRI to a repeated verb-generation task, we sought to distinguish cerebellar involvement in learning of item-specific noun-verb association and automation of verb generation skill. The same set of nouns was repeated in six verb-generation blocks so that subjects practiced generating verbs for the nouns. The practice was followed by a novel block with a different set of nouns. The cerebellar vermis (IV/V) and the right cerebellar lobule VI showed decreased activation following practice; activation in the right cerebellar Crus I was significantly lower in the novel challenge than in the initial verb-generation task. Furthermore, activation in this region during well-practiced blocks strongly correlated with improvement of behavioral performance in both the well-practiced and the novel blocks, suggesting its role in the learning of general mental skills not specific to the practiced noun-verb pairs. Therefore, the cerebellum processes both explicit verbal associative learning and automation of cognitive tasks. Different cerebellar regions predominate in this processing: lobule VI during the acquisition of item-specific association, and Crus I during automation of verb-generation skills through practice.

Adaptation to Visuomotor Rotation and Force Field Perturbation Is Correlated to Different Brain Areas in Patients With Cerebellar Degeneration

Although it is widely agreed that the cerebellum is necessary for learning and consolidation of new motor tasks, it is not known whether adaptation to kinematic and dynamic errors is processed by the same cerebellar areas or whether different parts play a decisive role. We investigated arm movements in a visuomotor (VM) rotation and a force field (FF) perturbation task in 14 participants with cerebellar degeneration and 14 age- and gender-matched controls. Magnetic resonance images were used to calculate the volume of cerebellar areas (medial, intermediate, and lateral zones of the anterior and posterior lobes) and to identify cerebellar structure important for the two tasks. Corroborating previous studies, cerebellar participants showed deficits in adaptation to both tasks compared with controls (P < 0.001). However, it was not possible to draw conclusions from the performance in one task on the performance in the other task because an individual participant could show severe impairment in one task and perform relatively well in the other (rho = 0.1; P = 0.73). We found that atrophy of distinct cerebellar areas correlated with impairment in different tasks. Whereas atrophy of the intermediate and lateral zone of the anterior lobe correlated with impairment in the FF task (rho = 0.72, 0.70; P = 0.003, 0.005, respectively), atrophy of the intermediate zone of the posterior lobe correlated with adaptation deficits in the VM task (rho = 0.64; P = 0.015). Our results suggest that adaptation to the different tasks is processed independently and relies on different cerebellar structures.

Cerebellar transcranial magnetic stimulation impairs verbal working memory

Previous functional magnetic resonance imaging and patient studies indicate cerebellar participation in verbal working memory. In particular, event-related functional magnetic resonance imaging showed superior cerebellar activation during the initial encoding phase of the Sternberg task. This study used functional magnetic resonance imaging-guided transcranial magnetic stimulation (TMS) to test whether disruption of the right superior cerebellum (hemispheric lobule VI/Crus I) impairs verbal working memory performance. Single-pulse TMS was administered immediately after letter presentation during the encoding phase on half the trials. Sham TMS and a Motor Control task were included to test for general distraction and nonmemory-related motor effects. Results showed no effects of TMS on accuracy, but reaction times (RTs) on correct trials were significantly increased on TMS relative to non-TMS trials for the Verbal Working Memory and Motor Control tasks. Additional analyses showed that the increased RT was significantly greater for Verbal Working Memory than for the motor task, suggesting that the effect on working memory was not caused by interference with finger responses. Sham TMS did not affect RTs, indicating that the potentially distracting effects of the postencoding click did not contribute to the increase in RT. The observed effects from cerebellar disruption are consistent with proposed cerebrocerebellar involvement in verbal working memory.

Stimulation of the superior cerebellar peduncle during the development of amygdaloid kindling in rats

Cerebellar manipulations have been used successfully in some intractable epileptic patients, however, their intrinsic mechanisms are not fully understood. To further clarify the cerebellar participation in epilepsy, we stimulated 10 rats with 100 Hz, 20 μA at the superior cerebellar peduncle (SCP) during amygdaloid kindling. Results were compared to 10 rats with an electrode placed at the SCP without stimulation and 10 rats without electrodes at the SCP used as control. We found that SCP stimulation increased the theta and alpha rhythms at the contralateral motor cortex. Such a stimulation produced hypertonicity of the forelimbs and tremor of the head. In this condition, we found that each of the behavioral stages during amygdaloid kindling in the SCP stimulated rats was reached earlier, while the amygdaloid electrographic afterdischarges (ADs) were longer during the first and shorter in the final trials as compared to controls. Moreover, amygdaloid ADs recorded exclusively during the behavioral stage-5 were significantly shorter than those recorded in the control conditions. We suggest that SCP stimulation could change the customary electrographic and convulsive expression of amygdala kindling in such a manner as to initially facilitate the limbic seizures and impede the secondary generalized seizures.

Cerebellum and speech perception: a functional magnetic resonance imaging study.

A variety of data indicate that the cerebellum participates in perceptual tasks requiring the precise representation of temporal information. Access to the word form of a lexical item requires, among other functions, the processing of durational parameters of verbal utterances. Therefore, cerebellar dysfunctions must be expected to impair word recognition. In order to specify the topography of the assumed cerebellar speech perception mechanism, a functional magnetic resonance imaging study was performed using the German lexical items "Boden" ([bodn], Engl. "floor") and "Boten" ([botn], "messengers") as test materials. The contrast in sound structure of these two lexical items can be signaled either by the length of the wordmedial pause (closure time, CLT; an exclusively temporal measure) or by the aspiration noise of wordmedial "d" or "t" (voice onset time, VOT; an intrasegmental cue). A previous study found bilateral cerebellar disorders to compromise word recognition based on CLT whereas the encoding of VOT remained unimpaired. In the present study, two series of "Boden - Boten" utterances were resynthesized, systematically varying either in CLT or VOT. Subjects had to identify both words "Boden" and "Boten" by analysis of either the durational parameter CLT or the VOT aspiration segment. In a subtraction design, CLT categorization as compared to VOT identification (CLT - VOT) yielded a significant hemodynamic response of the right cerebellar hemisphere (neocerebellum Crus I) and the frontal lobe (anterior to Broca's area). The reversed contrast ( VOT - CLT) resulted in a single activation cluster located at the level of the supratemporal plane of the dominant hemisphere. These findings provide first evidence for a distinct contribution of the right cerebellar hemisphere to speech perception in terms of encoding of durational parameters of verbal utterances. Verbal working memory tasks, lexical response selection, and auditory imagery of word strings have been reported to elicit activation clusters of a similar location. Conceivably, representation of the temporal structure of speech sound sequences represents the common denominator of cerebellar participation in cognitive tasks acting on a phonetic code.

Subcortical correlates of craving in recently abstinent alcoholic patients.

This study investigated functional cerebral correlates of craving in alcoholic patients and examined the state/trait characteristics of the regional cerebral network implicated in craving. Functional magnetic resonance imaging (fMRI) was used to map cerebral response elicited by ethanol odor in 10 male patients with alcohol dependence who had undergone detoxification and 10 matched nonpatients. After 3 weeks, during which the patients underwent standardized behavioral therapy with psychopharmacological intervention, all subjects were studied a second time with fMRI to evaluate the effects of therapy on the functional cerebral correlates of craving. In the alcoholic patients, cue-induced craving before treatment elicited activation primarily in the subcortical-limbic region of the right amygdala/hippocampal area and in the cerebellum. After treatment, activation was found in the superior temporal sulcus, while subcortical or cerebellar participation was no longer present. Comparison subjects showed no comparable amygdala or cerebellar activation during ethanol stimulation and demonstrated no change in activation pattern between measurements. This investigation points to state-dependent neurobiological correlates of cue-induced craving in alcoholic patients and suggests that these correlates can be influenced by therapeutic interventions. The presence of emotional aspects of craving is suggested by amygdala activation.

Mutism and Cerebellar Dysarthria after Brain Stem Surgery

Transient mutism resolving to cerebellar speech after posterior fossa surgery is a well-recognized phenomenon, particularly in pediatric patients. The anatomic basis for this postoperative functional change is unclear but may reside in the dominant superior cerebellar hemisphere or the medial deep cerebellar nuclei. We report a case of an 8-year-old girl who presented for surgical resection of a cavernous malformation of the right pons (at the level of the middle cerebellar peduncle) after hemorrhage. Preoperatively, her complaints consisted of contralateral motor deficits. She had normal speech. Her lesion was resected through a subtemporal approach to the pons. She awoke unable to speak. She was able to communicate through a variety of verbal cues, including sign language. Her mutism lasted 12 days after which she underwent a prolonged period of slowly resolving cerebellar dysarthria. Her preoperative motor deficits also slowly resolved. This is the first reported case of mutism resolving to cerebellar dysarthria after a supratentorial approach to the brain stem. We discuss the anatomic basis for postoperative mutism in light of previous observations combined with the unusual finding of mutism after pontine surgery. In particular, reports of mutism after bilateral cerebellar hemispheric injury, bilateral or unilateral medial deep nuclear injury, and, now, pontine tegmental injury implicate the superior cerebellar hemispheres, the deep cerebellar nuclei, and the nuclear outflow through the superior cerebellar peduncle as the anatomic bases for cerebellar participation in the production of human speech.

Parallel pathways for movement initiation of monkeys.

Participation of the pathway from the cerebellum through "motor" thalamus to motor cortex in movement initiation was tested in three. Cebus monkeys. The animals performed a simple reaction time (RT) task involving prompt elbow flexion or extension in response to an audiovisual "GO!" signal. RTs were not changed by reversible cooling of the arm area of the contralateral ventral lateral (VL) thalamus, that includes rostral VPL. In contrast, cooling the cerebellar dentate nucleus ipsilateral to the operant arm prolonged RTs by about 80 ms, as tested in two of the same monkeys. The results confirm cerebellar participation in prompt generation of well-learned intended arm movements; but they also indicate that although the route through VL-thalamus may be important, it is not essential for initiation of the same movements.

Cerebellar participation in generation of prompt arm movements

ArticlesCerebellar participation in generation of prompt arm movementsJ. Meyer-Lohmann, J. Hore, and V. B. BrooksJ. Meyer-Lohmann, J. Hore, and V. B. BrooksPublished Online:01 Sep 1977https://doi.org/10.1152/jn.1977.40.5.1038MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByClimbing fibers predict movement kinematics and performance errorsMartha L. Streng, Laurentiu S. Popa, and Timothy J. Ebner14 September 2017 | Journal of Neurophysiology, Vol. 118, No. 3Role of the cerebellum in the control and adaptation of gait in health and diseaseAbnormal cutaneomotor integration in patients with cerebellar syndromes: a transcranial magnetic stimulation studyClinical Neurophysiology, Vol. 114, No. 4Cerebellar Control of Constrained and Unconstrained Movements. I. Nuclear InactivationH. P. Goodkin and W. T. Thach1 February 2003 | Journal of Neurophysiology, Vol. 89, No. 2Interhemispheric neural summation in the split brain: effects of stimulus colour and taskNeuropsychologia, Vol. 41, No. 7Local Field Potential Oscillations in Primate Cerebellar Cortex: Modulation During Active and Passive ExpectancyRichard Courtemanche, Jean-Pierre Pellerin, and Yves Lamarre1 August 2002 | Journal of Neurophysiology, Vol. 88, No. 2Cerebellar Contribution to Speech Production evaluated by fMRINeuroImage, Vol. 7, No. 4Effects of Inactivating Individual Cerebellar Nuclei on the Performance and Retention of an Operantly Conditioned Forelimb MovementM. S. Milak, Y. Shimansky, V. Bracha, and J. R. Bloedel1 August 1997 | Journal of Neurophysiology, Vol. 78, No. 2The relationship between monkey ventrolateral thalamic nucleus activity and kinematic parameters of wrist movementBrain Research, Vol. 736, No. 1-2Discharge of identified deep cerebellar nuclei neurons related to eye blinks in the alert catNeuroscience, Vol. 61, No. 3Effect of cooling the dentate nucleus of the cerebellum on hand movement of the monkeyBrain Research, Vol. 629, No. 1The cerebellum participates in mental activity: tomographic measurements of regional cerebral blood flowBrain Research, Vol. 535, No. 2Contributions of the motor cortex and the cerebellum to a simple learned movement in the monkeyNeuroscience Letters, Vol. 46, No. 2Single cell studies of the primate putamenExperimental Brain Research, Vol. 53, No. 2Pyramidal input to the intracerebellar nuclei of the catNeuroscience, Vol. 9, No. 2Response characteristics of cerebellar dentate and lateral cortex neurons to sinusoidal stimulation of neck and labyrinth receptorsNeuroscience, Vol. 7, No. 12Modifications occurring in motor programs during learning of a complex task in manBrain Research, Vol. 241, No. 1Cortical field potentials preceding visually initiated hand movements and cerebellar actions in the monkey3 September 2013 | Experimental Brain Research, Vol. 46, No. 1Participation of the cerebellar dentate nucleus in the control of a goal-directed movement in monkeys3 September 2013 | Experimental Brain Research, Vol. 46, No. 1Activity of neurons of cerebellar nuclei during fictitious scratch reflex in the cat. II. Interpositus and lateral nucleiBrain Research, Vol. 200, No. 2Is the cerebellum really a computer?Trends in Neurosciences, Vol. 2Cerebellar modulation of reflex gainProgress in Neurobiology, Vol. 13, No. 4Learning of pursuit visuo-motor tracking by monkeysPhysiology & Behavior, Vol. 21, No. 6The role of internal pallidal segment on the initiation of a goal directed movementNeuroscience Letters, Vol. 9, No. 2-3Dentate cooling in monkeys performing a visuo-motor pointing taskNeuroscience Letters, Vol. 8, No. 3 More from this issue > Volume 40Issue 5September 1977Pages 1038-1050 Copyright & PermissionsCopyright © 1977 the American Physiological Societyhttps://doi.org/10.1152/jn.1977.40.5.1038PubMed409807History Published online 1 September 1977 Published in print 1 September 1977 Metrics