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Enrico Marani - One of the best experts on this subject based on the ideXlab platform.
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Effects of STN DBS and auditory cueing on the performance of sequential movements and the occurrence of Action Tremor in Parkinson’s disease
Journal of NeuroEngineering and Rehabilitation, 2014Co-Authors: Tjitske Heida, Eva Christine Wentink, Yan Zhao, Enrico MaraniAbstract:Background Parkinson’s disease (PD) patients show a higher ability to perform repetitive movements when they are cued by external stimuli, suggesting that rhythmic synchronization with an auditory timekeeper can be achieved in the absence of intact basal ganglia function. Deep brain stimulation (DBS) is another therapeutic method that improves movement performance in PD and may suppress or enhance Action Tremor. However, the combined effect of these therapies on Action Tremor has not been studied yet. In this pilot study, we thus test the effect of both DBS in the subthalamic nucleus (STN) and auditory cueing on movement performance and Action Tremor. Methods 7 PD patients treated with (bilateral) STN DBS were asked to move one hand or foot between two dots, separated by 30 cm as indicated on the table or the floor. The movement frequency was dictated by a metronome with a frequency in the range of 1.6 to 4.8 Hz. Each test was repeated three times for each extremity, with different stimulation settings applied during each repetition. The power spectral density patterns of recorded movements were studied. Tremor intermittency was taken into account by classifying each 2-second window of the recorded angular velocity signals as a Tremor or non-Tremor window. By determining the phase locking value it was tested whether movement or Tremor was synchronized with the auditory cue. Results While Action Tremor presence or absence did not affect the level of synchronization of the movement signal with the auditory cue for the different metronome frequencies, the number of extremities showing Action Tremor was significantly reduced under external cueing conditions in combination with DBS. In this respect the cueing frequencies of 1.6 and 4.8 Hz showed similar effects, suggesting that the frequency of the cueing signal is not that critical. Conclusion The combination of deep brain stimulation and auditory cueing, which both are proposed to involve the activation of cerebellar circuits, shows an enhanced Action Tremor reduction in Parkinson’s disease.
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power spectral density analysis of physiological rest and Action Tremor in parkinson s disease patients treated with deep brain stimulation
Journal of Neuroengineering and Rehabilitation, 2013Co-Authors: Tjitske Heida, E C Wentink, Enrico MaraniAbstract:Observation of the signals recorded from the extremities of Parkinson’s disease patients showing rest and/or Action Tremor reveal a distinct high power resonance peak in the frequency band corresponding to Tremor. The aim of the study was to investigate, using quantitative measures, how clinically effective and less effective deep brain stimulation protocols redistribute movement power over the frequency bands associated with movement, pathological and physiological Tremor, and whether normal physiological Tremor may reappear during those periods that Tremor is absent. The power spectral density patterns of rest and Action Tremor were studied in 7 Parkinson’s disease patients treated with (bilateral) deep brain stimulation of the subthalamic nucleus. Two tests were carried out: 1) the patient was sitting at rest; 2) the patient performed a hand or foot tapping movement. Each test was repeated four times for each extremity with different stimulation settings applied during each repetition. Tremor intermittency was taken into account by classifying each 3-second window of the recorded angular velocity signals as a Tremor or non-Tremor window. The distribution of power over the low frequency band ( 7.5 Hz – normal physiological Tremor) revealed that rest and Action Tremor show a similar power-frequency shift related to Tremor absence and presence: when Tremor is present most power is contained in the Tremor frequency band; when Tremor is absent lower frequencies dominate. Even under resting conditions a relatively large low frequency component became prominent, which seemed to compensate for Tremor. Tremor absence did not result in the reappearance of normal physiological Tremor. Parkinson’s disease patients continuously balance between Tremor and Tremor suppression or compensation expressed by power shifts between the low frequency band and the Tremor frequency band during rest and voluntary motor Actions. This balance shows that the pathological Tremor is either on or off, with the latter state not resembling that of a healthy subject. Deep brain stimulation can reverse the balance thereby either switching Tremor on or off.
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quantitative assessment of rest and Action Tremor and the effect of cueing in parkinson s disease patients treated with deep brain stimulation
Parkinsonism & Related Disorders, 2012Co-Authors: Tjitske Heida, E C Wentink, Enrico MaraniAbstract:Introduction: In Parkinson’s disease rest and Action Tremor may occur. High frequency deep brain stimulation in basal ganglia nuclei has proved to be effective in the suppression of Tremor. In addition, rhythmic auditory cues have shown to result in improved performance of repetitive movements, possibly by suppressing Action Tremor. The aim of this study was to investigate if electrical stimulation has similar effects on rest and Action Tremor, and whether in case of Action Tremor, the effect of electrical stimulation is similar to or enhanced by auditory cueing. Methods: Three exercises were carried out by 7 Parkinson’s disease patients treated with deep brain stimulation of the subthalamic nucleus: 1) sitting at rest; 2) performing a hand tapping movement as fast as possible; 3) performing hand movements on the rhythm of an auditory cueing signal. Inertial sensors registered the movement of the hands during the tests. The exercises were repeated for four different stimulation settings. Results: Electrical stimulation may either enhance or suppress rest and/or Action Tremor. Power spectral density analysis shows that Tremor suppression is accompanied by an increase in relative power in the low frequency band for both rest and Action Tremor. Most patients could (temporarily) phase lock their hand movements to the cueing signal of 1.6 Hz. Cueing signals at higher frequencies (3.2 and 4.8 Hz) could result in (n:m) phase locking of Tremor as well as movement. Conclusion: Electrical stimulation results in a re-scaling of Tremor, while auditory cueing may enhance suppression.
Elan D. Louis - One of the best experts on this subject based on the ideXlab platform.
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Action Tremor asymmetry profile does not aggregate in families with essential Tremor
Frontiers in Neurology, 2017Co-Authors: Elan D. Louis, Nora Hernandez, Karen P Chen, Kelly V Naranjo, Jemin Park, Lorraine N Clark, Ruth OttmanAbstract:Background: Action Tremor is the hallmark feature of essential Tremor (ET). While the Tremor typically is mildly asymmetric, in some patients, it is markedly asymmetric. There are few data on factors that influence this asymmetry. ET is also a highly familial disease. Whether the Tremor asymmetry profile (i.e., differential expression of Tremor in each arm in a given patient) is similar across family members is not known. The alternative possibility is that this feature is not heritable. There are no published data addressing this issue. The aim of this study was to determine whether the extent of Action Tremor asymmetry ran in ET families. Methods: ET probands and relatives were enrolled in a genetic study at Yale and Columbia Universities. An in-person evaluation included a videotaped neurological examination, including a detailed assessment of Tremors. A senior movement disorders neurologist reviewed all videotaped examinations, and the severity of postural and kinetic arm Tremors was rated on 12 examination items using a reliable rating scale. The Tremor asymmetry index = right arm Tremor score – left arm Tremor score. We used a bivariate linear regression model to assess the predictors of the Tremor asymmetry index in relatives; this model used the Tremor asymmetry index in the proband as a primary predictor of interest. In an analysis of variance (ANOVA), we tested for heterogeneity across families in the Tremor asymmetry index (i.e., to see whether there was a significant family effect). Results: There were 187 enrollees (59 probands, 128 affected relatives). In a bivariate linear regression model, the Tremor asymmetry index in the proband was not a predictor of the Tremor asymmetry index in their relatives (p = 0.66). In an ANOVA, family grouping did not explain a significant proportion of the total variance in the Tremor asymmetry index (p = 0.56). Conclusions: Tremor asymmetry did not aggregate in families with ET. Therefore, this does not seem to be a disease feature that is heritable. These data will provide added value to the clinical dialogue, giving patients one more piece of information about the way the disease manifests within families.
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another case of shopping bag Tremor a difficult to classify Action Tremor
Tremor and other hyperkinetic movements (New York N.Y.), 2014Co-Authors: Daphne Robakis, Elan D. LouisAbstract:This letter was written in response to : Zesiewicz T, Vu T, Carranza MA, et al. Unusual wrist Tremor: unilateral isometric Tremor? Tremor Other Hyperkinet Mov. 2014; 4: http://Tremorjournal.org/article/view/194
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Brief Reports Harmaline-Induced Tremor in Mice: Videotape Documentation and Open Questions about the Model
2013Co-Authors: Melody M. Cheng, Guomei Tang, Sheng-han Kuo, Elan D. LouisAbstract:Background: Harmaline-induced Tremor in rodents has been extensively used as an animal model for essential Tremor (ET). However, there is no visual documentation in the published literature. Methods: We injected mice subcutaneously with either 20 mg/kg of harmaline hydrochloride or saline and then videotaped the responses. Results: Action and postural Tremor in the mouse began 5 minutes after subcutaneous harmaline injection and peaked at approximately 30 minutes. The Tremor involved the head, trunk, tail, and four limbs and lasted for approximately 2 hours. The forelimb Tremor was postural or Action Tremor, similar to that observed in ET. Discussion: This video segment provides the first visual documentation of the phenomenology of harmaline-induced Tremor in a mouse. We also raise several unanswered questions regarding the use of harmaline-induced Tremor to model ET.
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screening for Action Tremor in epidemiological field surveys assessing the reliability of a semi quantitative visual template based scale for rating hand drawn spirals
Tremor and other hyperkinetic movements (New York N.Y.), 2012Co-Authors: Elan D. Louis, Qianhua Zhao, Haijiao Meng, Ding DingAbstract:Background: Population-based epidemiological studies of essential and other Tremors have need of a rapid yet accurate means to assess Tremor, especially mild Tremors. Handwriting is often affected by Tremor, and a hand-drawn spiral can provide investigators with objective rather than self-reported data. We present a semi-quantitative, ordinal scale to rate hand-drawn spirals. The scale, which includes values for mild Tremor, is accompanied by photographic examples of spirals of each rating, providing a visual template for guidance. Methods: This study, conducted within the framework of a population-based epidemiological study of 5,000 individuals aged 60 and older in Shanghai, asked enrollees to draw an Archimedes spiral with each hand. Spirals were rated using an ordinal scale (0, 0.5, 1, 1.5, 2, and 3). Three raters rated an initial set of 548 spirals. Four raters rated a subsequent set of 200 spirals using a visual template for guidance. Results: Initial agreement (548 spirals) was good (r values ranged from 0.49 to 0.62, all p<0.001). Subsequent agreement (200 spirals and using visual template) improved (r values ranged from 0.67 to –0.91, all p<0.001). Discussion: This tool will be useful to researchers who are attempting to rapidly assess Action Tremor in their field surveys.
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Action Tremor of the legs in essential Tremor prevalence clinical correlates and comparison with age matched controls
Parkinsonism & Related Disorders, 2009Co-Authors: Kathleen L Poston, Eileen Rios, Elan D. LouisAbstract:The hallmark feature of essential Tremor (ET) is Action Tremor of the arms. Leg Tremor may also occur yet it has not been the central focus of previous study. Its prevalence has only rarely been reported and its clinical correlates have yet to be explored. Our aims were to report the prevalence and analyze the clinical correlates of leg Action Tremor in patients with ET and, given the propensity for normal elderly individuals to manifest mild limb Tremors, compare the prevalence with that in age-matched controls. Kinetic leg Tremor rated ≥1 Tremor occurred in 28/63 (44.4%) ET cases and only 9/63 (14.3%) controls (p <0.001); moderate leg Tremor occurred in 14.3% of cases. Leg Tremor severity modestly correlated with disease duration (r = 0.31, p=0.02). However, the severity and laterality of leg Tremor did not correlate with that of arm Tremor. The pathophysiological implications of this finding deserve further exploration.
Tjitske Heida - One of the best experts on this subject based on the ideXlab platform.
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Effects of STN DBS and auditory cueing on the performance of sequential movements and the occurrence of Action Tremor in Parkinson’s disease
Journal of NeuroEngineering and Rehabilitation, 2014Co-Authors: Tjitske Heida, Eva Christine Wentink, Yan Zhao, Enrico MaraniAbstract:Background Parkinson’s disease (PD) patients show a higher ability to perform repetitive movements when they are cued by external stimuli, suggesting that rhythmic synchronization with an auditory timekeeper can be achieved in the absence of intact basal ganglia function. Deep brain stimulation (DBS) is another therapeutic method that improves movement performance in PD and may suppress or enhance Action Tremor. However, the combined effect of these therapies on Action Tremor has not been studied yet. In this pilot study, we thus test the effect of both DBS in the subthalamic nucleus (STN) and auditory cueing on movement performance and Action Tremor. Methods 7 PD patients treated with (bilateral) STN DBS were asked to move one hand or foot between two dots, separated by 30 cm as indicated on the table or the floor. The movement frequency was dictated by a metronome with a frequency in the range of 1.6 to 4.8 Hz. Each test was repeated three times for each extremity, with different stimulation settings applied during each repetition. The power spectral density patterns of recorded movements were studied. Tremor intermittency was taken into account by classifying each 2-second window of the recorded angular velocity signals as a Tremor or non-Tremor window. By determining the phase locking value it was tested whether movement or Tremor was synchronized with the auditory cue. Results While Action Tremor presence or absence did not affect the level of synchronization of the movement signal with the auditory cue for the different metronome frequencies, the number of extremities showing Action Tremor was significantly reduced under external cueing conditions in combination with DBS. In this respect the cueing frequencies of 1.6 and 4.8 Hz showed similar effects, suggesting that the frequency of the cueing signal is not that critical. Conclusion The combination of deep brain stimulation and auditory cueing, which both are proposed to involve the activation of cerebellar circuits, shows an enhanced Action Tremor reduction in Parkinson’s disease.
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power spectral density analysis of physiological rest and Action Tremor in parkinson s disease patients treated with deep brain stimulation
Journal of Neuroengineering and Rehabilitation, 2013Co-Authors: Tjitske Heida, E C Wentink, Enrico MaraniAbstract:Observation of the signals recorded from the extremities of Parkinson’s disease patients showing rest and/or Action Tremor reveal a distinct high power resonance peak in the frequency band corresponding to Tremor. The aim of the study was to investigate, using quantitative measures, how clinically effective and less effective deep brain stimulation protocols redistribute movement power over the frequency bands associated with movement, pathological and physiological Tremor, and whether normal physiological Tremor may reappear during those periods that Tremor is absent. The power spectral density patterns of rest and Action Tremor were studied in 7 Parkinson’s disease patients treated with (bilateral) deep brain stimulation of the subthalamic nucleus. Two tests were carried out: 1) the patient was sitting at rest; 2) the patient performed a hand or foot tapping movement. Each test was repeated four times for each extremity with different stimulation settings applied during each repetition. Tremor intermittency was taken into account by classifying each 3-second window of the recorded angular velocity signals as a Tremor or non-Tremor window. The distribution of power over the low frequency band ( 7.5 Hz – normal physiological Tremor) revealed that rest and Action Tremor show a similar power-frequency shift related to Tremor absence and presence: when Tremor is present most power is contained in the Tremor frequency band; when Tremor is absent lower frequencies dominate. Even under resting conditions a relatively large low frequency component became prominent, which seemed to compensate for Tremor. Tremor absence did not result in the reappearance of normal physiological Tremor. Parkinson’s disease patients continuously balance between Tremor and Tremor suppression or compensation expressed by power shifts between the low frequency band and the Tremor frequency band during rest and voluntary motor Actions. This balance shows that the pathological Tremor is either on or off, with the latter state not resembling that of a healthy subject. Deep brain stimulation can reverse the balance thereby either switching Tremor on or off.
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quantitative assessment of rest and Action Tremor and the effect of cueing in parkinson s disease patients treated with deep brain stimulation
Parkinsonism & Related Disorders, 2012Co-Authors: Tjitske Heida, E C Wentink, Enrico MaraniAbstract:Introduction: In Parkinson’s disease rest and Action Tremor may occur. High frequency deep brain stimulation in basal ganglia nuclei has proved to be effective in the suppression of Tremor. In addition, rhythmic auditory cues have shown to result in improved performance of repetitive movements, possibly by suppressing Action Tremor. The aim of this study was to investigate if electrical stimulation has similar effects on rest and Action Tremor, and whether in case of Action Tremor, the effect of electrical stimulation is similar to or enhanced by auditory cueing. Methods: Three exercises were carried out by 7 Parkinson’s disease patients treated with deep brain stimulation of the subthalamic nucleus: 1) sitting at rest; 2) performing a hand tapping movement as fast as possible; 3) performing hand movements on the rhythm of an auditory cueing signal. Inertial sensors registered the movement of the hands during the tests. The exercises were repeated for four different stimulation settings. Results: Electrical stimulation may either enhance or suppress rest and/or Action Tremor. Power spectral density analysis shows that Tremor suppression is accompanied by an increase in relative power in the low frequency band for both rest and Action Tremor. Most patients could (temporarily) phase lock their hand movements to the cueing signal of 1.6 Hz. Cueing signals at higher frequencies (3.2 and 4.8 Hz) could result in (n:m) phase locking of Tremor as well as movement. Conclusion: Electrical stimulation results in a re-scaling of Tremor, while auditory cueing may enhance suppression.
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rest and Action Tremor in parkinson s disease effects of deep brain stimulation
XII Mediterranean Conference on Medical and Biological Engineering and Computing 2010, 2010Co-Authors: Tjitske Heida, E C WentinkAbstract:One of the cardinal symptoms of Parkinson’s disease is rest Tremor. While rest Tremor generally disappears during sleep and voluntary movement, Action Tremor may be triggered by voluntary movement, and may even be more disabling than rest Tremor. Deep brain stimulation (DBS) in the subthalamic nucleus (STN) has been shown to be efficacious in the treatment of Tremor. However, in most studies Tremor is quantified using clinical scales such as the Unified Parkinson Disease Rating Scale (UPDRS). In this paper a pilot study is described in which the effect of DBS on rest and Action Tremor was investigated using inertial sensors for the quantification of Tremor.
Stanley Fahn - One of the best experts on this subject based on the ideXlab platform.
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case study first reported case of interferon alpha induced postural and Action Tremor p4 074
Neurology, 2014Co-Authors: David Rydz, Madeleine Sharp, Stanley FahnAbstract:OBJECTIVE: Our goal is to report a previously unknown side effect of pegylated interferon-alpha causing Action and postural Tremor during treatment for hepatitis C. BACKGROUND: Interferon alpha is associated with many neurological complications. Even though a variety of movement disorders, such as Parkinsonism, chorea, restless leg syndrome and dystonia, have been described with interferon use, to our knowledge, this is the first described case of both rest and Action Tremor. DESIGN/METHODS/RESULTS: We present a case study of a 58 year-old male who developed titubation and upper extremity resting and Action Tremor 20 weeks after initiation of therapy with pegylated interferon-alpha. The Tremor progressively worsened with ongoing therapy and stabilized but did not resolve when therapy was discontinued 8 weeks later. CONCLUSIONS: Tremor should be recognized as a possible side-effect of interferon-alpha and should be a consideration for therapy cessation as the sequelae may be protracted (as in our case) or even permanent. Disclosure: Dr. Rydz has nothing to disclose. Dr. Fahn has received personal compensation for activities with Merz Pharma, AstraZeneca Pharmaceuticals, and IMPAX Pharmaceuticals as a consultant; and Sun Pharmaceuticals as a teacher. Dr. Fahn has received personal compensation in an editorial capacity for Current Neurology and Neurosurgery Report, and Principles and Practice of Movement Disorders.
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risk of Action Tremor in relatives of Tremor dominant and postural instability gait disorder pd
Neurology, 2003Co-Authors: Elan D. Louis, Lucien J. Cote, Gilberto Levy, Helen Mejiasantana, Howard Andrews, Juliette Harris, Cheryl Waters, Blair Ford, Steven J Frucht, Stanley FahnAbstract:Background: Action Tremor may be more prevalent in relatives of patients with Parkinson’s disease (PD) than in relatives of control subjects. This Tremor could represent mild PD or essential Tremor. An estimate of the risk of this condition in families of patients with PD is important when studying the genetics of PD. Objectives: To determine the risk of Action Tremor in first-degree relatives of probands with Tremor-dominant PD (TD-PD) and postural instability gait disorder PD (PIGD-PD) compared with first-degree relatives of control probands. Methods: PD and control probands participated in a familial aggregation study of PD. The presence of Action Tremor in their relatives was ascertained from reports of one or more informants. Relatives who met diagnostic criteria for PD were excluded. Cox proportional hazards models adjusting for gender, education, race, and vital status (dead vs alive) of the relatives were used to assess the relative risk (RR) of Action Tremor in first-degree relatives of PD probands vs first-degree relatives of control probands. Results: There were 487 PD probands, 409 control probands, and 5,563 relatives. The risk of Action Tremor was higher in the relatives of TD-PD probands than in the relatives of control probands (RR = 2.14; 95% CI = 1.53 to 2.98) but not in the relatives of PIGD-PD probands compared with the relatives of control probands (RR = 1.81; 95% CI = 0.66 to 5.02). Conclusion: The risk of Action Tremor was increased in the relatives of PD probands, particularly when they had TD-PD. Whether the Tremor in these relatives represents essential Tremor or an isolated manifestation of PD requires further investigation.
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Clinical correlates of Action Tremor in Parkinson disease.
Archives of Neurology, 2001Co-Authors: Elan D. Louis, Lucien J. Cote, Gilberto Levy, H. Mejia, Stanley Fahn, Karen MarderAbstract:Background Action Tremor is often noted in patients with Parkinson disease (PD), yet the clinical correlates of this type of Tremor have been the focus of few studies. It is not clear whether this Action Tremor is a manifestation of the underlying basal ganglia disease. Objective To determine whether the severity of Action Tremor in PD is associated with age, age at disease onset, disease duration, levodopa dose, severity of rest Tremor, or other motor (ie, bradykinesia, rigidity) and nonmotor manifestations of PD. Methods Patients with PD (N = 197) were ascertained as part of a familial aggregation study. All patients underwent a neurological examination. Rest Tremor was rated with the Unified Parkinson Disease Rating Scale; and Action Tremor, with the Washington Heights–Inwood Genetic Study of Essential Tremor Rating Scale. Results Action Tremor was present in 184 (93.4%) of 197 patients. Four patients (2%) met criteria for definite essential Tremor. The Action Tremor score was not associated with age, age at onset, or disease duration. The Action Tremor score was associated with the rest Tremor score ( r = 0.37; P r = 0.21, P Conclusions Action Tremor was associated with rest Tremor in PD, suggesting that, at least in part, Action Tremor is a manifestation of the underlying basal ganglia disease. Neither Tremor was associated with other motor and nonmotor manifestations of PD. This in turn suggests that Tremor in PD may represent an underlying pathophysiological process different from these other manifestations.
Paul J Hagerman - One of the best experts on this subject based on the ideXlab platform.
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the primary cognitive deficit among males with fragile x associated Tremor ataxia syndrome fxtas is a dysexecutive syndrome
Journal of Clinical and Experimental Neuropsychology, 2008Co-Authors: Angela G Brega, Glenn K Goodrich, Rachael E Bennett, David R Hessl, Karen Engle, Maureen A Leehey, Lanee S Bounds, Marsha J Paulich, Randi J Hagerman, Paul J HagermanAbstract:Fragile X-associated Tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder associated with a premutation trinucleotide repeat expansion in the fragile X mental retardation 1 gene. Symptoms include gait ataxia, Action Tremor, and cognitive impairment. The objectives of the study were to clarify the nature of the dysexecutive syndrome observed in FXTAS and to assess the contribution of executive impairment to deficits in nonexecutive cognitive functions. Compared to controls, men with FXTAS demonstrated significant executive impairment, which was found to mediate group differences in most other cognitive abilities. Asymptomatic premutation carriers performed similarly to controls on all but two measures of executive functioning. These findings suggest that the impairment of nonexecutive cognitive skills in FXTAS is in large part secondary to executive dysfunction.
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intention Tremor parkinsonism and generalized brain atrophy in male carriers of fragile x
Neurology, 2001Co-Authors: Randi J Hagerman, Maureen A Leehey, W Heinrichs, Flora Tassone, Rebecca Wilson, J Hills, Jim Grigsby, B Gage, Paul J HagermanAbstract:The authors report five elderly men with the fragile X premutation who had a progressive Action Tremor associated with executive function deficits and generalized brain atrophy. These individuals had elevated fragile X mental retardation 1 gene (FMR1) messenger RNA and normal or borderline levels of FMR1 protein. The authors propose that elevations of FMR1 messenger RNA may be causative for a neurodegenerative syndrome in a subgroup of elderly men with the FMR1 premutation.
