PubMed Health⌕ Search

Biomedical subjects

I Litvan

Publications and source records attributed to I Litvan.

At least 19 recordsLinked to original sources

Herbicide exposure modifies GSTP1 haplotype association to Parkinson onset age: the GenePD Study.

BACKGROUND: Polymorphisms in the glutathione S-transferase pi gene (GSTP1), encoding GSTP1-1, a detoxification enzyme, may increase the risk of Parkinson disease (PD) with exposure to pesticides. Using the GenePD Study sample of familial PD cases, we explored whether GSTP1 polymorphisms were associated with the age at onset of PD symptoms and whether that relation was modified by exposure to herbicides. METHODS: Seven single-nucleotide polymorphisms (SNPs) were genotyped and tested for association with PD onset age in men in three strata: no exposure to herbicides, residential exposure to herbicides, and occupational exposure to herbicides. Haplotypes were similarly evaluated in stratified analyses. RESULTS: Three SNPs were associated with PD onset age in the group of men occupationally exposed to herbicides. Three additional SNPs had significant trends for the association of PD onset age across the herbicide exposure groups. Haplotype results also provided evidence that the relation between GSTP1 and onset age is modified by herbicide exposure. One haplotype was associated with an approximately 8-years-earlier onset in the occupationally exposed group and a 2.8-years-later onset in the nonexposed group. CONCLUSIONS: Herbicide exposure may be an effect modifier of the relation between glutathione S-transferase pi gene polymorphisms and onset age in familial PD.

Disease Susceptibility↗

Measuring quality of life in PSP: the PSP-QoL.

OBJECTIVE: To develop a new patient-reported outcome measure for progressive supranuclear palsy (PSP) and to test its psychometric properties. METHODS: First, the authors generated a pool of potential scale items from in-depth patient interviews. Second, the authors administered these items, in the form of a questionnaire, to a sample of people with PSP and traditional psychometric methods were used to develop a rating scale satisfying standard criteria for reliability and validity. Third, the authors examined the psychometric properties of the rating scale in a second sample. RESULTS: In stage 1, a pool of 87 items was generated from 27 patient interviews. In stage 2, a scale with two subscales (physical, 22 items; mental, 23 items), satisfying standard criteria for reliability and validity, was developed from the response data of 225 patients with PSP. In stage 3, the scale was examined in 188 people with PSP. Missing data were low, scores in both subscales were evenly distributed, floor and ceiling effects were small. Reliability was high (Cronbach's alpha 0.93, 0.95; test-retest 0.95, 0.92). Validity was supported by the interscale intercorrelation (0.60), factor analysis, and the magnitude and pattern of correlations with four other rating scales, disease severity, and disease duration. The psychometric properties of the new scale were similar in the United Kingdom and North America, and in clinic- and community-based samples studied. CONCLUSIONS: The Progressive Supranuclear Palsy Quality of Life scale (PSP-QoL) may be a helpful patient-reported scale for clinical trials and studies in PSP.

Aged↗

BDNF genetic variants are associated with onset age of familial Parkinson disease: GenePD Study.

Brain-derived neurotrophic factor (BDNF) stimulates neuronal growth and protects nigral dopamine neurons in animal models of Parkinson disease (PD). Therefore, BDNF is a candidate gene for PD. The authors investigated five single-nucleotide polymorphisms in 597 cases of familial PD. Homozygosity for the rare allele of the functional BDNF G196A (Val66Met) variant was associated with a 5.3-year older onset age (p = 0.0001). These findings suggest that BDNF may influence PD onset age.

Age of Onset↗

Diagnosis and management of dementia with Lewy bodies: third report of the DLB Consortium.

The dementia with Lewy bodies (DLB) Consortium has revised criteria for the clinical and pathologic diagnosis of DLB incorporating new information about the core clinical features and suggesting improved methods to assess them. REM sleep behavior disorder, severe neuroleptic sensitivity, and reduced striatal dopamine transporter activity on functional neuroimaging are given greater diagnostic weighting as features suggestive of a DLB diagnosis. The 1-year rule distinguishing between DLB and Parkinson disease with dementia may be difficult to apply in clinical settings and in such cases the term most appropriate to each individual patient should be used. Generic terms such as Lewy body (LB) disease are often helpful. The authors propose a new scheme for the pathologic assessment of LBs and Lewy neurites (LN) using alpha-synuclein immunohistochemistry and semiquantitative grading of lesion density, with the pattern of regional involvement being more important than total LB count. The new criteria take into account both Lewy-related and Alzheimer disease (AD)-type pathology to allocate a probability that these are associated with the clinical DLB syndrome. Finally, the authors suggest patient management guidelines including the need for accurate diagnosis, a target symptom approach, and use of appropriate outcome measures. There is limited evidence about specific interventions but available data suggest only a partial response of motor symptoms to levodopa: severe sensitivity to typical and atypical antipsychotics in approximately 50%, and improvements in attention, visual hallucinations, and sleep disorders with cholinesterase inhibitors.

Brain↗

"Applause sign" helps to discriminate PSP from FTD and PD.

The "applause sign" is a simple test of motor control that helps to differentiate PSP from frontal or striatofrontal degenerative diseases. It was found in 0/39 controls, 0 of 24 patients with frontotemporal dementia (FTD), 0 of 17 patients with Parkinson disease (PD), and 30/42 patients with progressive supranuclear palsy (PSP). It discriminated PSP from FTD (p < 0.001) and PD (p < 0.00). The "three clap test" correctly identified 81.8% of the patients in the comparison PSP and FTD and 75% of the patients in the comparison of PSP and PD.

Aged↗

Bilateral subthalamotomy in Parkinson's disease: initial and long-term response.

We conducted an open label pilot study of the effect of bilateral subthalamotomy in 18 patients with advanced Parkinson's disease. In seven patients, the first subthalamotomy pre-dated the second by 12-24 months ('staged surgery'). Subsequently, a second group of 11 patients received bilateral subthalamotomy on the same day ('simultaneous surgery'). Patients were assessed according to the CAPIT (Core Assessment Program for Intracerebral Transplantation) protocol, a battery of timed motor tests and neuropsychological tests. Evaluations were performed in the 'off' and 'on' drug states before surgery and at 1 and 6 months and every year thereafter for a minimum of 3 years after bilateral subthalamotomy. Compared with baseline, bilateral subthalamotomy induced a significant (P < 0.001) reduction in the 'off' (49.5%) and 'on' (35.5%) Unified Parkinson's Disease Rating Scale (UPDRS) motor scores at the last assessment. A blind rating of videotape motor exams in the 'off' and 'on' medication states preoperatively and at 2 years postoperatively also revealed a significant improvement. All of the cardinal features of Parkinson's disease as well as activities of daily living (ADL) scores significantly improved (P < 0.01). Levodopa-induced dyskinesias were reduced by 50% (P < 0.01), and the mean daily levodopa dose was reduced by 47% at the time of the last evaluation compared with baseline (P < 0.0001). Dyskinesias occurred intraoperatively or in the immediate postoperative hours in 13 patients, but were generally mild and short lasting. Three patients developed severe generalized chorea that gradually resolved within the next 3-6 months. Three patients experienced severe and persistent postoperative dysarthria. In two, this coincided with the patients exhibiting large bilateral lesions also suffering from severe dyskinesias. No patient exhibited permanent cognitive impairment. The motor benefit has persisted for a follow-up of 3-6 years. This study indicates that bilateral subthalamotomy may induce a significant and long-lasting improvement of advanced Parkinson's disease, but the clinical outcome was variable. This variability may depend in large part on the precise location and volume of the lesions. Further refinement of the surgical procedure is mandatory.

Activities of Daily Living↗

Cognitive and behavioral aspects of PSP since Steele, Richardson and Olszewski's description of PSP 40 years ago and Albert's delineation of the subcortical dementia 30 years ago.

Although researchers are now familiar with progressive supranuclear palsy (PSP) and its characteristic "subcortical" dementia, this was not the case prior to seminal descriptions by Steele, Richardson, Olszewski and Albert. In fact, the first three authors identified this disorder, and the last one introduced the classification of the dementias according to the anatomical involvement. This paper is in honor of their contributions, and will also outline the changes that have occurred since their seminal works.

Behavior↗

Yes/no reversals as neurobehavioral sequela: a disorder of language, praxis, or inhibitory control?

This study identifies a linguistic phenomenon suggestive of damage to fronto-subcortical circuitry. Our objective was to determine the occurrence and neuroradiological/neurobehavioral correlates of yes/no reversals in corticobasal degeneration (CBD), and document occurrence of reversals in other neurological conditions. In a prospective study, we evaluated 34 CBD patients using a neuropsychologic battery and magnetic resonance imaging. Patients were subdivided into two groups: those with (n = 11) and without (n = 23) yes/no reversals. In a retrospective study conducted during the period of 1991-2001, we identified 33 patients for whom yes/no reversals occurred to compare correlates with prospective study findings. In the prospective study, 11 patients (32.3%) had yes/no reversals. Significant between-group differences were found in scores of lexical fluency (P = 0.02) and prehension (P = 0.03). Prehension scores correlated with facial praxis (P < 0.0001) and upper limb praxis scores (P < 0.0001) in the yes/no reversal group only. In the retrospective study, nine CBD patients and 24 non-CBD patients had yes/no reversals, with damage to fronto-subcortical areas present in all patients. Results suggest an association with deficits in mental flexibility and inhibitory control. High within-group correlations of lexical fluency and prehension with praxis scores suggest a relationship of yes/no reversals with multiple factors.

Aged↗

Performance on the dementia rating scale in Parkinson's disease with dementia and dementia with Lewy bodies: comparison with progressive supranuclear palsy and Alzheimer's disease.

BACKGROUND: The relation between dementia with Lewy bodies (DLB) and Parkinson's disease with dementia (PDD) is unknown. OBJECTIVES: To compare the cognitive profiles of patients with DLB and PDD, and compare those with the performance of patients with a subcortical dementia (progressive supranuclear palsy) and a cortical dementia (Alzheimer's disease). DESIGN: Survey of cognitive features. SETTING: General community in Rogaland county, Norway, and a university dementia and movement disorder research centre in the USA. PATIENTS: 60 patients with DLB, 35 with PDD, 49 with progressive supranuclear palsy, and 29 with Alzheimer's disease, diagnosed by either standardised clinical procedures and criteria (all PDD and Alzheimer cases and 76% of cases of progressive supranuclear palsy), or necropsy (all DLB cases and 24% of cases of progressive supranuclear palsy). Level of dementia severity was matched using the total score on the dementia rating scale adjusted for age and education. MAIN OUTCOME MEASURES: Dementia rating scale subscores corrected for age. RESULTS: No significant differences between the dementia rating scale subscores in the PDD and DLB groups were found in the severely demented patients; in patients with mild to moderate dementia the conceptualisation subscore was higher in PDD than in DLB (p = 0.03). Compared with Alzheimer's disease, PDD and DLB had higher memory subscores (p < 0.001) but lower initiation and perseveration (p = 0.008 and p=0.021) and construction subscores (p = 0.009 and p = 0.001). DLB patients had a lower conceptualisation subscore (p = 0.004). Compared with progressive supranuclear palsy, PDD and DLB patients had lower memory subscores (p < 0.001). CONCLUSIONS: The cognitive profiles of patients with DLB and PDD were similar, but they differed from those of patients with Alzheimer's disease and progressive supranuclear palsy. The cognitive pattern in DLB and PDD probably reflects the superimposition of subcortical deficits upon deficits typically associated with Alzheimer's disease.

Aged↗

Office of Rare Diseases neuropathologic criteria for corticobasal degeneration.

A working group supported by the Office of Rare Diseases of the National Institutes of Health formulated neuropathologic criteria for corticobasal degeneration (CBD) that were subsequently validated by an independent group of neuropathologists. The criteria do not require a specific clinical phenotype, since CBD can have diverse clinical presentations, such as progressive asymmetrical rigidity and apraxia, progressive aphasia, or frontal lobe dementia. Cortical atrophy, ballooned neurons, and degeneration of the substantia nigra have been emphasized in previous descriptions and are present in CBD, but the present criteria emphasize tau-immunoreactive lesions in neurons, glia, and cell processes in the neuropathologic diagnosis of CBD. The minimal pathologic features for CBD are cortical and striatal tau-positive neuronal and glial lesions, especially astrocytic plaques and thread-like lesions in both white matter and gray matter, along with neuronal loss in focal cortical regions and in the substantia nigra. The methods required to make this diagnosis include histologic stains to assess neuronal loss, spongiosis and ballooned neurons, and a method to detect tau-positive neuronal and glial lesions. Use of either the Gallyas silver staining method or immunostains with sensitive tau antibodies is acceptable. In cases where ballooned neurons are sparse or difficult to detect, immunostaining for phospho-neurofilament or alpha-B-crystallin may prove helpful. Methods to assess Alzheimer-type pathology and Lewy body pathology are necessary to rule out other causes of dementia and Parkinsonism. Using these criteria provides good differentiation of CBD from other tauopathies, except frontotemporal dementia and Parkinsonism linked to chromosome 17, where additional clinical or molecular genetic information is required to make an accurate diagnosis.

Atrophy↗

Traumatic brain injury as a risk factor for Alzheimer disease. Comparison of two retrospective autopsy cohorts with evaluation of ApoE genotype.

BACKGROUND AND PURPOSE: The impact of traumatic brain injury (TBI) on the pathogenesis of Alzheimer disease (AD) is still controversial. The aim of our retrospective autopsy study was to assess the impact of TBE and ApoE allele frequency on the development of AD. MATERIAL AND METHODS: We examined 1. the incidence of AD pathology (Braak stageing, CERAD, NIA-Reagan Institute criteria) in 58 consecutive patients (mean age +/- SD 77.0 +/- 6.8 years) with residual closed TBI lesions, and 2. the frequency of TBI residuals in 57 age-matched autopsy proven AD cases. In both series, ApoE was evaluated from archival paraffin-embedded brain material. RESULTS: 1. TBE series: 12.1 % showed definite and 10.3% probable AD (mean age 77.6 and 75.2 years), only 2/13 with ApoEepsilon3/4. From 45 (77.6%) non-AD cases (mean age 78.2 years), 3 had ApoEepsilon3/4. The prevalence of 22.4% AD in this small autopsy cohort was significantly higher than 3.3% in a recent large clinical series and 14% in the general population over age 70. 2. In the AD cohort with ApoEepsilon4 allele frequency of 30% similar to other AD series, residuals of closed TBI were seen in 4 brains (7%) (mean age +/- SD 78.2 +/- 6.4), all lacking the ApoEepsilon4 allele. TBI incidence was slightly lower than 8.5% in the clinical MIRAGE study. CONCLUSIONS: The results of this first retrospective autopsy study of TBI, ApoEepsilon allele frequency, and AD confirm clinical studies suggesting severe TBI to be a risk factor for the development AD higher in subjects lacking ApoEepsilon4 alleles. Further studies in larger autopsy series are needed to elucidate the relationship between TBI, genetic predisposition, and AD.

Aged↗

Randomized placebo-controlled trial of donepezil in patients with progressive supranuclear palsy.

OBJECTIVE: There is no effective treatment for progressive supranuclear palsy (PSP). Because results of immunochemical and pharmacologic studies suggest that the cholinergic system may play a role in the cognitive and motor features of PSP, the authors investigated the effects of donepezil (10 mg/day), an acetylcholinesterase inhibitor, in 21 patients with PSP (mean age +/- SD; 65.7 +/- 4.7 years) by a randomized, double-blind, placebo-controlled crossover trial. METHODS: Donepezil and placebo were administered for 6 weeks each with a 1-month washout period. Patients were evaluated before and at the end of each treatment phase. Outcome measures evaluated neuropsychiatric, global cognitive, frontal, memory, motor, and activities of daily living (ADL) status. RESULTS: Two patients withdrew during the washout phase because of unrelated medical problems. Donepezil-induced systemic side effects were transient and generally mild. Because of worsening of motor function, three patients received 5 mg/day of donepezil. All patients achieved blood and CSF therapeutic levels of donepezil. While the patients were taking donepezil, their Double Memory Test scores improved, whereas their ADL/mobility scores significantly worsened. CONCLUSION: The findings suggest that acetylcholinesterase inhibitors such as donepezil have at best selective, modest effects on cognition in patients with PSP. In light of its deleterious effects on ADL/mobility, donepezil is not recommended for this patient population.

Aged↗

Tau genotype: no effect on onset, symptom severity, or survival in progressive supranuclear palsy.

Genetic studies have shown that progressive supranuclear palsy (PSP) is associated with inheritance of a specific genotype (H1/H1) in the tau gene. The authors investigated whether the H1/H1 genotype or A0/A0 genotype independently or in conjunction with selected environmental risk factors influences the age at onset, severity, or survival in patients with PSP. Our findings suggest that tau genotyping does not predict the prognosis of PSP.

Age of Onset↗

Corticobasal degeneration and progressive supranuclear palsy share a common tau haplotype.

OBJECTIVE: To analyze the association of polymorphisms in the tau gene with pathologically confirmed corticobasal degeneration (CBD). BACKGROUND: The authors previously described an extended tau haplotype (H1) that covers the human tau gene and is associated with the development of progressive supranuclear palsy (PSP). The authors now extend this analysis to CBD, a neurodegenerative condition with clinical and neuropathologic similarities to PSP. Like PSP, CBD is associated with accumulation of aggregates containing the 4-repeat isoforms of tau. Because of difficulty in diagnosis of CBD, the authors only analyzed cases with pathologically confirmed CBD. METHODS: The authors collected 57 unrelated, neuropathologically confirmed cases of CBD. Tau sequencing in these cases failed to show the presence of pathogenic mutations. Polymorphisms that spanned the tau gene were analyzed in all CBD cases and controls. RESULTS: Analyzing tau polymorphisms in CBD cases showed that the frequency of H1 and H1/H1 was significantly increased when analyzing all cases and when separating by country of origin. H1 frequency in all CBD cases was 0.921, compared with a control frequency of 0.766 (X(2) = 9.1, p = 0.00255 [1df], OR 3.56 [8.43 > CI 95% > 1.53]). The H1/H1 frequency was also significantly higher at 0.842 compared with 0.596 in age-matched controls (X(2) = 17.42, p = 0.00016, 2df), OR 3.61 [7.05 > CI 95% > 1.85]). CONCLUSIONS: The CBD tau association described here suggests that PSP and CBD share a similar cause, although the pathogenic mechanism behind the two diseases leads to a different clinical and pathologic phenotype.

Genotype↗

Comparison of apraxia in corticobasal degeneration and progressive supranuclear palsy.

OBJECTIVE: To describe ideomotor apraxia in patients with corticobasal degeneration and those with progressive supranuclear palsy, two parkinsonian disorders that are often misdiagnosed due to the overlap in their clinical features, and to determine whether systematic apraxia testing is useful for differential diagnosis. METHODS: Fourteen patients fulfilling National Institute of Neurological Disorders and Stroke-Society for Progressive Supranuclear Palsy clinical criteria for progressive supranuclear palsy, 13 patients fulfilling modified Lang criteria for corticobasal degeneration, and 12 normal healthy control subjects were given the Test of Oral and Limb Apraxia, which was scored according to the Florida Apraxia Battery for occurrence of various types of apraxic errors. RESULTS: Both patients with progressive supranuclear palsy and corticobasal degeneration committed a greater number of apraxic errors than normal healthy control subjects on both transitive and intransitive tasks (p < 0.001 in both cases), but apraxia was much more severe in patients with corticobasal degeneration than progressive supranuclear palsy (p < 0.001). The index of apraxia severity, in combination with the assessment of the two key features of progressive supranuclear palsy (falls and vertical gaze palsy), correctly classified all patients. CONCLUSIONS: Patients with corticobasal degeneration show more severe ideomotor apraxia than patients with progressive supranuclear palsy, and systematic assessment of ideomotor apraxia facilitates the differential diagnosis between patients with progressive supranuclear palsy and those with corticobasal degeneration.

Aged↗

Progression of dysarthria and dysphagia in postmortem-confirmed parkinsonian disorders.

BACKGROUND: Dysarthria and dysphagia are known to occur in parkinsonian syndromes such as Parkinson disease (PD), dementia with Lewy bodies (DLB), corticobasal degeneration (CBD), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Differences in the evolution of these symptoms have not been studied systematically in postmortem-confirmed cases. OBJECTIVE: To study differences in the evolution of dysarthria and dysphagia in postmortem-confirmed parkinsonian disorders. PATIENTS AND METHODS: Eighty-three pathologically confirmed cases (PD, n = 17; MSA, n = 15; DLB, n = 14; PSP, n = 24; and CBD, n = 13) formed the basis for a multicenter clinicopathological study organized by the National Institute of Neurological Disorders and Stroke, Bethesda, Md. Cases with enough clinicopathological documentation for the purpose of the study were selected from research and neuropathological files of 7 medical centers in 4 countries (Austria, France, England, and the United States). RESULTS: Median dysarthria latencies were short in PSP and MSA (24 months each), intermediate in CBD and DLB (40 and 42 months), and long in PD (84 months). Median dysphagia latencies were intermediate in PSP (42 months), DLB (43 months), CBD (64 months), and MSA (67 months), and long in PD (130 months). Dysarthria or dysphagia within 1 year of disease onset was a distinguishing feature for atypical parkinsonian disorders (APDs) (specificity, 100%) but failed to further distinguish among the APDs. Survival time after onset of a complaint of dysphagia was similar in PD, MSA, and PSP (15 to 24 months, P =.7) and latency to a complaint of dysphagia was highly correlated with total survival time (rho = 0.88; P<.001) in all disorders. CONCLUSIONS: Latency to onset of dysarthria and dysphagia clearly differentiated PD from the APDs, but did not help distinguish different APDs. Survival after onset of dysphagia was similarly poor among all parkinsonian disorders. Evaluation and adequate treatment of patients with PD who complain of dysphagia might prevent or delay complications such as aspiration pneumonia, which in turn may improve quality of life and increase survival time.

Aged↗

Impairment of eyeblink classical conditioning in progressive supranuclear palsy.

In a previous study we showed that learning in eyeblink classical conditioning (EBCC) is normal in Parkinson's disease (PD) and that the serial reaction time task (SRTT) is only marginally impaired. Since pathological lesions are more widespread in the atypical parkinsonian disorder of progressive supranuclear palsy (PSP) than in PD, we hypothesized that PSP patients may show more profound deficits in the EBCC and SRTT learning tasks. We therefore investigated EBCC with a delay and two trace paradigms, an SRTT and the California Verbal Learning Test (CVLT) in eight patients with PSP and an age-matched control group. In all EBCC paradigms, we found a significant difference between groups with no significant learning in PSP patients. In the SRTT, implicit learning may have been impaired, but verbal and manual sequence recall were only marginally impaired. Verbal memory was significantly worse in PSP patients than in the control group. Our study shows a dissociated pattern of learning abilities in PSP, where the EBCC as a measure of implicit learning is impaired, the explicit sequence detection in the SRTT is relatively preserved, and the verbal memory impaired. We hypothesize that the PSP patients' deficits in EBCC learning may be due to lesions of deep cerebellar nuclei. There may be a clinical role for EBCC in distinguishing PD and PSP patients.

Aged↗

Neuropsychiatric assessment of Gilles de la Tourette patients: comparative study with other hyperkinetic and hypokinetic movement disorders.

The role of the basal ganglia in conditions with co-occurring movement disorders and neuropsychiatric symptoms is not well known. It has been hypothesized that hyperkinesia -disinhibited behaviors and hypokinesia-inhibited behaviors result from an imbalance between the direct and indirect striatal output pathways, and that differential involvement of these pathways could account for the concurrent abnormalities in movement and behavior observed in these disorders. This study aimed to evaluate whether the pattern and the extent of the neuropsychiatric manifestations of patients with GTS, a hyperkinetic movement disorder of basal ganglia origin, differs from that of patients with other basal ganglia hyperkinetic (e.g., HD) or hypokinetic (e.g., PSP) movement disorders, and to determine whether patients with GTS show a greater frequency of hyperactive behaviors (e.g., agitation, irritability, euphoria, or anxiety) than PSP patients, and are comparable to patients with HD. The Neuropsychiatric Inventory (NPI), a scale with established validity and reliability, was administered to 26 patients with GTS (mean age, 30.2 +/- 2.2 years), and the results were compared with that of 29 patients with HD (mean age, 43.8 +/- 2 years) and 34 with PSP (mean +/- S.D. age, 66.6 +/- 1.2 years). There was no difference between the groups in the total NPI scores. However, there was a double dissociation in behaviors: patients with hyperkinetic disorders (HD and GTS) exhibited significantly more agitation, irritability, anxiety, euphoria, and hyperkinesia, whereas hypokinetic patients (PSP) exhibited more apathy. Patients with GTS showed greater scores than HD patients in all those scores differentiating HD and GTS from PSP patients (e.g., agitation, irritability, anxiety and euphoria), and were differentiated in a logistic regression analysis from both HD and PSP patients in having significantly more anxiety. We found that patients with GTS manifested predominantly hyperactive behaviors similar but more pronounced than those presented by patients with HD, while those with PSP manifested hypoactive behaviors. Based on our findings and the proposed models of basal ganglia dysfunction in these disorders, we suggest that the hyperactive behaviors in GTS are comparable to those observed in HD, being both secondary to an excitatory subcortical output through the medial and orbitofrontal cortical circuits, while in PSP the hypoactive behaviors are secondary to hypostimulation of these circuits. Abnormalities of other brain structures (e.g., amygdala, brainstem nuclei) may account for the significantly higher anxiety scores differentiating GTS from HD patients.

Adult↗