PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “CEREBELLAR DISEASES”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

A speaking task analysis of the dysarthria in cerebellar disease.

Cerebellar disease affects a number of skilled movements, including those in speech. Ataxic dysarthria, the speech disorder that typically accompanies cerebellar disease, was studied by acoustic methods. Control subjects and subjects with ataxic dysarthria were recorded while performing a number of speaking tasks, including sustained vowel phonation, syllable repetition, monosyllabic word production (intelligibility test), sentence recitation, and conversation. Acoustic data derived from the speech samples confirmed the hypothesis that temporal dysregulation is a primary component of the speech disorder. The data also show that the nature of the disorder varies with the speaking task. This result agrees with observations on other motor systems in subjects with cerebellar disease and may be evidence of a dissociation of impairments. Suggestions are offered on the selection of measures for a given task and on the role of the cerebellum in the regulation of speaking.

Adult↗

A comparative study of simple and choice reaction time in Parkinson's, Huntington's and cerebellar disease.

The aim of the study was to compare the quantitative and qualitative similarities and differences in the performance of patients with Parkinson's disease, Huntington's disease and cerebellar disease on a number of reaction time tasks. Simple reaction time (SRT), uncued and fully cued four choice (CRT) tasks were performed by eight patients with Parkinson's disease after withdrawal of dopaminergic medication for an average of 14.4 hours; by seven non-demented patients with Huntington's disease and by eight patients with cerebellar disease. An S1 (warning signal/precue)-S2 (imperative stimulus) paradigm was used in all tasks, with the S1-S2 interval randomly varying between 0, 200, 800, 1600 and 3200 ms across trials. The patients with Huntington's disease had a significantly longer SRT than those with Parkinson's disease. None of the other group differences in uncued and unwarned SRT and CRT was significant. For the patients with Parkinson's disease and those with cerebellar disease, unwarned SRT was faster than uncued and unwarned CRT. For the patients with Huntington's disease, this CRT/SRT difference was not significant. A warning signal before the imperative stimulus resulted in a reduction of reaction time in all three groups. Advance information provided by S1 about the response that would be required by S2 was used by patients in all three groups, evident from reaction times in the fully cued CRT task being faster than those in the uncued CRT condition. Patients with cerebellar disease had slower movement times in the SRT and CRT conditions compared with the patients with Parkinson's disease and Huntington's disease, whose times did not differ. In one SRT condition, when the absence of a warning signal was predictable, patients with cerebellar disease, and to a lesser extent those with Huntington's disease, were able to maintain a general motor readiness before the imperative stimulus. This was not the case for the patients with Parkinson's disease who seemed more dependent on the presence of a warning signal to reduce their reaction time. With a few exceptions, the pattern of results of the three groups were qualitatively similar. It may be concluded that similar reaction time deficits are found in Parkinson's disease, in patients with other disorders of the basal ganglia (Huntington's disease), as well as those with a disease sparing the basal ganglia (cerebellar disease). The non-specific slowness observed at the behavioural level may, however, have diverse central mechanisms.

Adult↗

Speech disorders in cerebellar disease.

The areas of cerebellar damage most commonly associated with dysarthria were sought by reviewing the clinical, radiographic, surgical, and autopsy findings in patients with nondegenerative cerebellar disease. Case histories on 162 patients with focal cerebellar lesions were reviewed. All but 15 of the patients underwent surgery, and 28 had autopsies. Thirty-one of the 122 patients with adequate descriptions of speech had dysarthria. Twenty-two of these 31 dysarthric patients had exclusively or predominantly left cerebellar hemisphere disease; 7 had right hemisphere disease; and 2 had vermal disease. Only 19 of 41 patients with exclusively or predominantly left hemisphere disease had had normal speech before surgery. Dysarthria developed in isolated cases following cerebellar resections extending into the paravermal segments of the left hemisphere. There was no correlation between the extent of vermal damage and development of abnormal speech. Cerebellar speech function was most commonly affected with damage to the superior portion of the left cerebellar hemisphere.

Adult↗

Psychopathology in patients with degenerative cerebellar diseases: a comparison to Huntington's disease.

OBJECTIVE: This study estimated the psychiatric morbidity of patients with degenerative cerebellar diseases. METHOD: The study included a series of 31 patients with degenerative cerebellar diseases, compared with 21 patients with Huntington's disease and 29 neurologically healthy comparison subjects. Comprehensive psychiatric evaluations, including the Structured Clinical Interview for DSM-IV and psychopathology rating scales, were administered. RESULTS: The overall rate of noncognitive psychiatric disorders was 77% in the patients with degenerative cerebellar diseases, nearly identical to that in the patients with Huntington's disease (81%) and about double that seen in the neurologically healthy subjects (41%). There were high rates of all mood disorders in both the degenerative cerebellar diseases group (68%) and the Huntington's disease group (43%); the rate in the degenerative cerebellar diseases group was significantly higher than that in the neurologically healthy subjects (31%). The frequency of personality change in the three groups was striking: change was present in 26% of the degenerative cerebellar diseases patients, 48% of the Huntington's disease patients, and none of the neurologically healthy comparison subjects. A total of 19% of the degenerative cerebellar diseases subjects and 71% of the Huntington's disease subjects met DSM-IV criteria for either cognitive disorder or dementia. CONCLUSIONS: The high rate of psychiatric and cognitive disorders in the patients with degenerative cerebellar diseases suggests that many, if not most, patients with degenerative cerebellar diseases may benefit from psychiatric interventions. These results also support previous findings that the cerebellum may have a role in modulating emotion and cognition.

Cerebellar Diseases↗

Ocular signs of cerebellar disease.

Ocular signs of cerebellar disease have been increasingly appreciated with the advent of means for quantitative recording of eye movements. The graphs in this article illustrate ocular flutter, dysmetria, abnormal (nonsmooth) pursuit, instability of fixation, faulty vestibular suppression, impaired optokinetic response, end-position nystagmus, and rebound nystagmus. The signs may be categorized as follows: (1) proprioceptive abnormalities manifest by flutter, dysmetria, and instability of gaze and (2) defects of vision-dependent functions manifest by abnormalities of pursuit, vestibular suppression, optokinetic response, and nystagmus.

Basal Ganglia↗

Respiratory kinematics in speakers with cerebellar disease.

The respiratory abilities of a group of 12 speech disordered subjects with cerebellar disease were assessed using both spirometric and kinematic techniques and compared to those of a group of 12 non-neurologically impaired controls matched for age and gender. Results of the spirometric assessment showed that although all of the cerebellar-diseased subjects had normal total lung capacities, almost half had vital capacities below normal limits. All except 1 of the cerebellar-diseased subjects exhibited irregularities in their chest wall movements while performing sustained vowel and syllable repetition tasks. Over half of the cerebellar-diseased subjects also displayed similar irregularities when reading and conversing. The same irregularities were not present in the chest wall movements exhibited by the control subjects suggesting that their presence was caused by the cerebellar disease. Results are discussed in terms of the effects of cerebellar disease on neuromuscular function.

Adult↗

Correlation of clinical signs with CT findings in patients with cerebellar disease.

The severity of cerebellar signs and the degree of cerebellar atrophy depicted by computed tomography (CT) were independently graded in 108 patients with cerebellar disorders. The overall agreement between these independently scaled measures was only 28%. In patients with involvement of the cerebellar hemispheres and anterior lobe, clinical signs tended to be more pronounced than the cerebellar atrophy revealed by CT. The opposite was true for patients with lesions of the caudal vermis. Patients with Friedreich's ataxia had no or only minor CT abnormalities. Close correlation between the degree of infra- and supratentorial atrophy was found only in chronic alcoholics. The poor correlation between changes in cerebellar structure detected by CT and clinical disability suggests the need for caution in CT interpretation.

Adolescent↗

Absence of a common functional denominator of visual disturbances in cerebellar disease.

Several studies have demonstrated disturbances of visual perception in patients suffering from cerebellar disease. In an attempt to determine the cause of these visual disturbances and thereby the cerebellar contribution to vision, we designed two sets of experiments in which we tested (i) the possibility of a general magnocellular deficit in cerebellar disease and (ii) the alternative possibility of impaired spatial attention underlying visual disturbances in cerebellar patients. The first set of experiments consisted of a test of position discrimination, a parvocellular function and tests tapping different aspects of motion perception including speed discrimination, direction discrimination and the ability to extract a coherent motion signal embedded in noise. The second set of experiments compared the performance on two different classes of texture discrimination. The first one required fast and precise shifts of focal spatial attention ('serial search'), the second one, testing preattentive texture discrimination ('pop-out'), did not. In the first set of experiments cerebellar patients were impaired on the position discrimination task as well as several, albeit not all, tests of motion perception. The pattern of disturbances obtained was neither compatible with the notion of a selective magnocellular deficit nor the idea, originally put forward by Ivry and Diener (J Cogn Neurosci 1991; 3: 355-66) that visual deficits are secondary to an impaired measurement of time. In the second set of experiments, cerebellar patients showed normal performance on pop-out tasks and normal performance on all variants of the serial search task except for the one requiring comparison of a single element presented with a sample of the target in short-term memory. In summary, our results support the existence of visual disturbances in cerebellar disease, but provide evidence against a common, simple denominator such as a timing deficit, deficient cerebellar modulation of magnocellular circuitry, deficits of spatial attention or visual working memory.

Adult↗

[Approach to chronic cerebellar diseases in children].

Cerebellar pathology in infants falls into two parts. The pathology that is accessible to a molecular approach is represented mainly by monogenic metabolic diseases of postnatal expression while the pathology that remains descriptive is represented mainly by congenital disorders of cerebellar development. These disorders may be associated with a variety of abnormalities defining a rapidly increasing number of syndromes. Identification of the numerous morphogenes involved in cerebellar development will probably result not only from extrapolation to man of homologous recombinations experiments but also from genetic investigations in exceptional clinical cases.

Cerebellar Diseases↗

Quantification of postural sway in normals and patients with cerebellar diseases.

Posturography was performed in 41 patients with cerebellar diseases by means of a force measuring platform using an on-line computer program which calculated sway path, sway area, antero-posterior and lateral sway components and the amount of visual stabilization. Postural ataxia was quantitatively studied in 8 patients with spinal ataxia (Friedreich's), 6 patients with vestibulocerebellar lesions, 11 patients with anterior lobe atrophy, 7 patients with hemispheral cerebellar lesions, and 9 patients with a disease affecting all parts of the cerebellum. Patients with lesions of the cerebellar hemispheres could not be separated from normals by means of posturography. Lesions of the spino-cerebellar afferents (Friedreich' ataxia) caused an omnidirectional low frequency sway with preserved visual stabilization. Patients with anterior lobe atrophy showed a predominant antero-posterior sway, often with a spontaneous high frequency body tremor around 3 Hz. Vestibulo-cerebellar lesions exhibited omnidirectional low frequency sway poorly stabilized by vision. Quantitative posturography helps to localize cerebellar lesions and allows for quantitative follow-up studies of cerebellar diseases.

Adult↗

Acoustic characteristics of dysarthria associated with cerebellar disease.

The speech of five individuals with cerebellar disease and ataxic dysarthria was studied with acoustic analyses of CVC words, words of varying syllabic structure (stem, stem plus suffix, stem plus two suffixes), simple sentences, the Rainbow Passage, and conversation. The most consistent and marked abnormalities observed in spectrograms were alterations of the normal timing pattern, with prolongation of a variety of segments and a tendency toward equalized syllable durations. Vowel formant structure in the CVC words was judged to be essentially normal except for transitional segments. The greater the severity of the dysarthria, the greater the number of segments lengthened and the degree of lengthening of individual segments. The ataxic subjects were inconsistent in durational adjustments of the stem syllable as the number of syllables in a word was varied and generally made smaller reductions than normal subjects as suffixes were added. Disturbances of syllable timing frequently were accompanied by abnormal contours of fundamental frequency, particularly monotone and syllable-falling patterns. These dysprosodic aspects of ataxic dysarthria are discussed in relation to cerebellar function in motor control.

Aged↗

A quantitative study of eye and head movements during smooth pursuit in patients with cerebellar disease.

Eye and head movements were analysed during smooth pursuit in 16 patients with various forms of cerebellar disease. Smooth pursuit gain was reduced across all frequencies and velocities of target motion for the patient group as a whole, during both sinusoidal and pseudo-random target motion. The graded breakdown in the pursuit response, as pseudo-random target motion became less predictable, was of a similar magnitude in patients and controls, implying that the predictive pursuit mechanisms were intact in these patients. During head-free pursuit, when vestibulo-ocular reflex (VOR) suppression was necessary, performance was not significantly different from that observed during head-fixed pursuit in the patient group. This finding is similar to that noted in control subjects, and is consistent with the observation that the VOR gains associated with head movements in darkness were similar in the patient and control groups. The deficits in pursuit and VOR suppression in patients with cerebellar disease therefore represent a decrease in gain in the closed-loop visual feedback pathways with apparent sparing of the predictive pathways.

Adult↗

Adaptation motor learning of arm movements in patients with cerebellar disease.

OBJECTIVE: To design a test of motor learning using arm movements in normal subjects and patients with cerebellar disease. METHODS: Elbow angle was continuously displayed as a cursor (a dot) on a computer screen, and subjects made ballistic elbow flexion and extension movements to try to move the cursor between two targets on the screen. The relation between the arm movement and its visual feedback was changed, and the subjects reacted by adapting the amplitude of their movements in subsequent trials. RESULTS: The consecutive errors showed exponential learning curves during adaptation, which were quantified by their steepness. Ten patients with isolated cerebellar or olivopontocerebellar degeneration had less steep learning curves than normal subjects, indicating a failure of adaptation motor learning in cerebellar disease. The results show that this test may be useful for the analysis of motor learning.

Adaptation, Physiological↗

Long latency muscle responses in cerebellar diseases.

Long latency reflexes were measured from the hand muscles of 27 patients suffering from different cerebellar diseases (12 diffuse cerebellar atrophies, 7 cerebellar hemispheric infarcts, 8 Friedreich's disease) and from 45 controls after electrical stimulus of the median nerve at the wrist. The M3 response (latency about 70 ms) was increased in about 50% of cerebellar atrophy cases and occasionally (10 of 12 cases) separated from the M2 response (50 ms). M3 was sometimes (3/7) increased and the M2-3 complex was prolonged ipsilaterally in cases of cerebellar infarcts. In the cases of Friedreich's ataxia M2 was always lost uni or bilaterally because of the disturbance of afferent or efferent fibres. The latencies of the spinal reflex M1 and also of M2 were not always increased strongly enough to be clearly separated from the normal values.

Adult↗

Inherited cerebellar diseases.

This chapter analyzes the neuropsychological deficits in inherited cerebellar diseases and compares their symptomatology with animal models in which the exact anatomical localization of degeneration is known and limited to the cerebellum. Both animal and human data suggest that cerebellar cortical atrophy affects functions of the frontal lobe system. Olivopontocerebellar atrophy is genetically and clinically in homogeneous. The dementia syndrome that occurs in a proportion of patients does not seem to be linked with cerebellar dysfunction. Patients suffering from Friedreich's disease have been described as exhibiting cognitive slowing and deficits in spatial tasks. Because other structures are more prominently involved than the cerebellum in this disease, other pathoanatomical correlates may explain the symptomatology.

Animals↗

Single-neuron analysis of human thalamus in patients with intention tremor and other clinical signs of cerebellar disease.

Tremor that occurs as a result of a cerebellar lesion, cerebellar tremor, is characteristically an intention tremor. Thalamic activity may be related to cerebellar tremor because transmission of some cerebellar efferent signals occurs via the thalamus and cortex to the periphery. We have now studied thalamic neuronal activity in a cerebellar relay nucleus (ventral intermediate-Vim) and a pallidal relay nucleus (ventralis oral posterior-Vop) during thalamotomy in patients with intention tremor and other clinical signs of cerebellar disease (tremor patients). The activity of single neurons and the simultaneous electromyographic (EMG) activity of the contralateral upper extremity in tremor patients performing a pointing task were analyzed by spectral cross-correlation analysis. EMG spectra during intention tremor often showed peaks of activity in the tremor-frequency range (1.9-5.8 Hz). There were significant differences in thalamic neuronal activity between tremor patients and controls. Neurons in Vim and Vop had significantly lower firing rates in tremor patients than in patients undergoing thalamic surgery for pain (pain controls). Other studies have shown that inputs to Vim from the cerebellum are transmitted through excitatory connections. Therefore the present results suggest that tremor in these tremor patients is associated with deafferentation of the thalamus from cerebellar efferent pathways. The thalamic X EMG cross-correlation functions were studied for cells located in Vim and Vop. Neuronal and EMG activity were as likely to be significantly correlated for cells in Vim as for those in Vop. Cells in Vim were more likely to have a phase lag relative to EMG than were cells in Vop. In monkeys, cells in the cerebellar relay nucleus of the thalamus, corresponding to Vim, are reported to lead movement during active oscillations at the wrist. In view of these monkey studies, the present results suggest that cells in Vim are deafferented and have a phase lag relative to tremor that is not found in normal active oscillations. The difference in phase of thalamic spike X EMG activity between Vim and Vop may contribute to tremor because lesions of pallidum or Vop are reported to relieve cerebellar tremor.

Action Potentials↗

Asymmetry of the pitch vestibulo-ocular reflex in patients with cerebellar disease.

Responses to pitch head impulses were measured in 15 patients with cerebellar degeneration and downbeat nystagmus and in 5 control subjects, using three-axis search coils. For each subject, response gains were calculated as (1) the ratio of instantaneous vertical eye velocity to pitch head velocity (at 30 ms and at 70 ms into the response), and (2) the ratio of peak eye velocity to peak head velocity. Gains varied more widely among patients. When calculated at 70 ms and using peak values, patients had higher gains for downward pitch, and normal subjects had symmetric gains. At 30 ms, gains were more symmetric in patients, but at that point control subjects actually had lower gains for downward pitch. Thus, the pitch gain ratio (ratio of downward gain to upward gain) was consistently greater in patients than in normal subjects. Because downward impulses were generally faster, eye velocities during downward and upward pitch for equivalent head speeds were also compared. Again, patients had higher gains for downward pitch. These results are consistent with the authors' hypothesis that cerebellar disease results in a higher sensitivity of anterior than posterior semicircular canal pathways, perhaps through loss of inhibition from the flocculus/paraflocculus complex on anterior canal secondary neurons in the vestibular nuclei. The pitch gain asymmetry was larger than, and did not correlate with, the velocity of spontaneous upward drift. This supports the notion that other mechanisms are likely to contribute to downbeat nystagmus in these patients.

Adult↗