Opposing patterns of abnormal D1 and D2 receptor dependent cortico-striatal plasticity explain increased risk taking in patients with DYT1 dystonia.

Patients with DYT1 dystonia caused by the mutated TOR1A gene exhibit risk neutral behaviour compared to controls who are risk averse in the same reinforcement learning task. It is unclear whether this behaviour can be linked to changes in cortico-striatal plasticity demonstrated in animal models which share the same TOR1A mutation. We hypothesised that we could reproduce the experimental risk taking behaviour using a model of the basal ganglia under conditions where cortico-striatal plasticity was abnormal. As dopamine exerts opposing effects on cortico-striatal plasticity via different receptors expressed on medium spiny neurons (MSN) of the direct (D1R dominant, dMSNs) and indirect (D2R dominant, iMSNs) pathways, we tested whether abnormalities in cortico-striatal plasticity in one or both of these pathways could explain the patient's behaviour. Our model could generate simulated behaviour indistinguishable from patients when cortico-striatal plasticity was abnormal in both dMSNs and iMSNs in opposite directions. The risk neutral behaviour of the patients was replicated when increased cortico-striatal long term potentiation in dMSN's was in combination with increased long term depression in iMSN's. This result is consistent with previous observations in rodent models of increased cortico-striatal plasticity at in dMSNs, but contrasts with the pattern reported in vitro of dopamine D2 receptor dependant increases in cortico-striatal LTP and loss of LTD at iMSNs. These results suggest that additional factors in patients who manifest motor symptoms may lead to divergent effects on D2 receptor dependant cortico-striatal plasticity that are not apparent in rodent models of this disease.

Neuropsychological and Neuropsychiatric Features of Idiopathic and DYT1 Dystonia and the Impact of Medical and Surgical treatment.

Dystonia is a hyperkinetic movement disorder, characterized by sustained or intermittent muscle contractions causing abnormal, often repetitive, movements, postures, or both. Executive dysfunction is a feature of cognitive function in idiopathic and DYT1 dystonia. Psychiatric morbidity is increased in dystonia, and depression, anxiety, obsessive compulsive disorders are the most common disorders. Sleep problems and pain are also frequently experienced. Evidence suggest that mood and anxiety disorders are intrinsic to the neurobiology of dystonia, but also that psychiatric co-morbidity can be secondary to pain experience and the psychosocial functioning and quality of life of the patients. Medical treatment of dystonia with botulinum toxin injections into affected muscles or with deep brain stimulation surgery improves the symptoms as well as mood and the quality of the patients and does not produce any adverse effects on cognitive function.

[Cognitive functions in patients with primary torsion dystonia treated with pallidal deep brain stimulation].

Forty-three patients with primary dystonia underwent neuropsychological assessment according to the method of A.R. Luria. Twenty-three patients with generalized dystonia and 20 with local forms (cervical and craniocervical) were included in the study. All patients were evaluated before pallidal deep brain stimulation (DBS GPi), 32 patients were examined 3-6 days after surgery, and 26 patients - during the first two years of the postoperative follow-up. The evaluation before surgery revealed cognitive impairment in 41 patients. The most common were mnemonic impairment, inertness and preservation in different tests, and spatial function decline. Thus, patients with local forms more frequently had troubles with performance memory tests, whereas spatial function disorders were more common in patients with generalized forms. The deterioration of cognitive functions was observed in 28 patients in the early postoperative period. Moreover, the group of patients with local forms had poorer results. The neuropsychological evaluation after 3-6 months of the postoperative follow-up showed the restoration of cognitive functions to the preoperative level. Neuropsychological syndrome observed in patients with dystonia was generally similar to that found in patients with lesions of the frontal lobe, the caudate nucleus, and the cerebellum.

Temporal discrimination thresholds in adult-onset primary torsion dystonia: an analysis by task type and by dystonia phenotype.

Adult-onset primary torsion dystonia (AOPTD) is an autosomal dominant disorder with markedly reduced penetrance. Sensory abnormalities are present in AOPTD and also in unaffected relatives, possibly indicating non-manifesting gene carriage (acting as an endophenotype). The temporal discrimination threshold (TDT) is the shortest time interval at which two stimuli are detected to be asynchronous. We aimed to compare the sensitivity and specificity of three different TDT tasks (visual, tactile and mixed/visual-tactile). We also aimed to examine the sensitivity of TDTs in different AOPTD phenotypes. To examine tasks, we tested TDT in 41 patients and 51 controls using visual (2 lights), tactile (non-painful electrical stimulation) and mixed (1 light, 1 electrical) stimuli. To investigate phenotypes, we examined 71 AOPTD patients (37 cervical dystonia, 14 writer's cramp, 9 blepharospasm, 11 spasmodic dysphonia) and 8 musician's dystonia patients. The upper limit of normal was defined as control mean +2.5 SD. In dystonia patients, the visual task detected abnormalities in 35/41 (85%), the tactile task in 35/41 (85%) and the mixed task in 26/41 (63%); the mixed task was less sensitive than the other two (p = 0.04). Specificity was 100% for the visual and tactile tasks. Abnormal TDTs were found in 36 of 37 (97.3%) cervical dystonia, 12 of 14 (85.7%) writer's cramp, 8 of 9 (88.8%) blepharospasm, 10 of 11 (90.1%) spasmodic dysphonia patients and 5 of 8 (62.5%) musicians. The visual and tactile tasks were found to be more sensitive than the mixed task. Temporal discrimination threshold results were comparable across common adult-onset primary torsion dystonia phenotypes, with lower sensitivity in the musicians.

Temporal discrimination threshold: VBM evidence for an endophenotype in adult onset primary torsion dystonia.

Familial adult-onset primary torsion dystonia is an autosomal dominant disorder with markedly reduced penetrance. Most adult-onset primary torsion dystonia patients are sporadic cases. Disordered sensory processing is found in adult-onset primary torsion dystonia patients; if also present in their unaffected relatives this abnormality may indicate non-manifesting gene carriage. Temporal discrimination thresholds (TDTs) are abnormal in adult-onset primary torsion dystonia, but their utility as a possible endophenotype has not been examined. We examined 35 adult-onset primary torsion dystonia patients (17 familial, 18 sporadic), 42 unaffected first-degree relatives of both familial and sporadic adult-onset primary torsion dystonia patients, 32 unaffected second-degree relatives of familial adult-onset primary torsion dystonia (AOPTD) patients and 43 control subjects. TDT was measured using visual and tactile stimuli. In 33 unaffected relatives, voxel-based morphometry was used to compare putaminal volumes between relatives with abnormal and normal TDTs. The mean TDT in 26 control subjects under 50 years of age was 22.85 ms (SD 8.00; 95% CI: 19.62-26.09 ms). The mean TDT in 17 control subjects over 50 years was 30.87 ms (SD 5.48; 95% CI: 28.05-33.69 ms). The upper limit of normal, defined as control mean + 2.5 SD, was 42.86 ms in the under 50 years group and 44.58 ms in the over 50 years group. Thirty out of thirty-five (86%) AOPTD patients had abnormal TDTs with similar frequencies of abnormalities in sporadic and familial patients. Twenty-two out of forty-two (52%) unaffected first-degree relatives had abnormal TDTs with similar frequencies in relatives of sporadic and familial AOPTD patients. Abnormal TDTs were found in 16/32 (50%) of second-degree relatives. Voxel-based morphometry analysis comparing 13 unaffected relatives with abnormal TDTs and 20 with normal TDTs demonstrated a bilateral increase in putaminal grey matter in unaffected relatives with abnormal TDTs. The prevalence of abnormal TDTs in sporadic and familial AOPTD patients and their first-degree relatives follows the rules for a useful endophenotype. A structural correlate of abnormal TDTs in unaffected first-degree relatives was demonstrated using voxel-based morphometry. Voxel-based morphometry findings indicate that putaminal enlargement in AOPTD is a primary phenomenon. TDTs may be an effective tool in AOPTD research with particular relevance to genetic studies of the disorder.

Increased risk for recurrent major depression in DYT1 dystonia mutation carriers.

BACKGROUND: Prior studies suggest that dystonia is comorbid with affective disorders. This comorbidity could be a reaction to a chronic debilitating disorder or expression of a predisposing gene. The authors took advantage of the identification of a gene for dystonia, DYT1, to test these alternative explanations. METHODS: The authors administered a standardized psychiatric interview to members of families with an identified DYT1 mutation. The authors classified family members into three groups: mutation carriers with dystonia (manifesting carriers; n = 96), mutation carriers without dystonia (non-manifesting carriers; n = 60), and noncarriers (n = 65). RESULTS: The risk for recurrent major depressive disorder was increased in both non-manifesting carriers (RR = 4.95, CI = 1.72 to 14.29) and manifesting carriers (RR = 3.62, CI = 1.00 to 10.53) compared with noncarriers. Mutation carriers also had earlier age at onset of recurrent major depressive disorder than noncarriers. The severity of motor signs was not associated with the likelihood of recurrent depression. Mutation carriers did not have an increased risk for other affective disorders, such as single major depression or bipolar disorder. CONCLUSIONS: Early-onset recurrent major depression is associated with the DYT1 GAG mutation and this association is independent of motor manifestations of dystonia. These findings suggest that early-onset recurrent depression is a clinical expression of the DYT1 gene mutation.

A novel quality of life instrument for deep brain stimulation in movement disorders.

OBJECTIVE: To develop a short instrument to examine quality of life (QoL) which specifically addresses patients with movement disorders treated by deep brain stimulation (DBS). DESIGN: The instrument was developed within an existing concept of a modular questionnaire (questions on life satisfaction: "general life satisfaction" QLS(M)-A, and "satisfaction with health" QLS(M)-G), in which each item is weighted according to its relative importance to the individual. METHODS: Items were generated by interviews with 20 DBS patients, followed by item reduction and scale generation, factor analysis to determine relevant and final questionnaire items, estimation of reliability, and validation based on the medical outcome study 36 item short form health survey (SF-36) and the EuroQol (EQ-5D) (data from 152 patients with Parkinson's disease, essential tremor, or idiopathic torsion dystonia, including 75 patients with DBS). RESULTS: Initial questionnaires were reduced to 12 items for a "movement disorder module" (QLS(M)-MD), and five items for a "deep brain stimulation module" (QLS(M)-DBS). Psychometric analysis revealed Cronbach's alpha values of of 0.87 and 0.73, and satisfactory correlation coefficients for convergent validity with SF-36 and EQ-5D. CONCLUSIONS: QLS(M)-MD and QLS(M)-DBS can evaluate quality of life aspects of DBS in movement disorders. Psychometric evaluation showed the questionnaires to be reliable, valid, and well accepted by the patients.

Hereditary non-progressive torsion dystonia with intellectual disturbance.

Three siblings of a consanguineous parents with involuntary movements are reported. The mother had only a very slight neck tremor, without any other neurological abnormality, and the father had died. The 38-year-old son (Case 1) complained of involuntary movements at the age of 6. His involuntary movements were observed in the tongue, perioral region and upper and lower extremities: jerky movements with dystonic features. The 46-year-old elder brother (Case 2) experienced involuntary movements at the age of 18. Involuntary movements were observed in the upper extremities; he also had torticollis and tremulous movements in the neck, and jerky movements in the perioral region. They showed gait disturbance and dysarthria. The 35-year-old sister (Case 3) also experienced involuntary movements. When she was writing, her involuntary movements were obvious: dystonia and myoclonic jerks. Tremor in the neck was also seen. Their intelligence was below average. We concluded that this family had hereditary torsion dystonia, with myoclonus, and low intelligence. This condition may be associated with an autosomal recessive gene.

[The dynamic mental status of patients who have undergone stereotaxic destruction of the ventrolateral thalamic nuclei]. / Dinamika psikhicheskogo sostoianiia bol'nykh, perenesshikh stereotaksicheskuiu destruktsiiu ventrolateral'nykh iader talamusa.

Examined were 80 patients with parkinsonism and 20 patients torsional dystonia before and after stereotaxic cryodestruction of the ventrolateral thalamic nuclei. A set of tests was used to evaluate attention, memory, associative processes, generalization, comprehension to examine these patients. Only in the group of parkinson patients a reduction of these findings was noted (memory, perception, comprehension). All other mental activity types suffered similarly in all patients after the operations.

Does neurology inform psychoanalysis? A case report.

In these days of malpractice suits it has become increasingly important that the psychoanalyst make correct diagnoses and institute appropriate treatment. The significance of this statement is enhanced by the fact that the opinion is being increasingly enunciated that there is no such disorder as conversion hysteria. Accordingly the psychoanalyst needs to keep up to date about relevant neurological matters. The present article reports a case of a young women who had been treated psychoanalytically for many years without the organic nature of her disorder being grasped. Appropriate pharmacological therapy produced prolonged remission of her symptoms.

Behavioral covariation in the treatment of chronic pain.

The successful use of operant procedures to alter behaviors associated with various medical conditions suggests that such behaviors may be learned and that the principles of learning may be applied not only to treatment but also to the study of the pathogenesis of illness behavior. The present study, conducted within an ongoing neuromuscular research project, assessed the covariation of behaviors associated with chronic pain within and across behavioral and drug approaches to treatment. Problems of screaming and five other behaviors (including self-reports of pain) were measured across conditions of varying behavioral contingencies (noncontingent reinforcement vs the removal of reinforcement contingent upon screaming) and varying administration (time since medication and dosage) of Parsidol during attempts to treat the muscle pain of a 24-year-old male with a severe, chronic neuromuscular disorder diagnosed as dystonia musculorum deformans (DMD). Results indicated that: (a) pain behaviors covaried during behavioral and drug conditions even though the behavioral intervention only targeted screaming; (b) effects were greater on nontargeted behaviors during periods that followed rather than preceded drug administration; (c) in contrast to behavioral observation data, physiological measures of neuromuscular activity (EMG) did not differ across conditions. These results suggest that functional response-response relationships exist in patients as the result of their illness experience.

[Dystonia musculorum deformans. Elements of a favorable development]. / Dystonie musculaire déformante. Eléments d'une évolution favorable.

The therapeutic benefits of a concomitant approach to the disease and to the patient's identity experienced by the authors is illustrated by this case of a child presenting with dystonia musculorum deformans and severe disturbances of identity. This work was part of a research program concerning the function of these approaches and the operative modalities of their combinations.

MMPI characteristics associated with cerebral palsy and dystonia musculorum deformans.

The origins of dystonia musculorum deformans are now considered to be organic. However, misdiagnosis of dystonia as a functional psychiatric disorder--usually conversion reaction--has persisted. The present study describes personality traits as measured by the Minnesota Multiphasic Personality Inventory in 30 persons with dystonia and in a control group of 37 persons with cerebral palsy. The data, examined by diagnosis, level of disability, and sex, showed no differences for diagnostic groups or levels of disability. Males scored in the direction of greater psychopathology than did females. The male dystonics showed the highest elevations of MMPI scales of all the groups. Although only one person with dystonia musculorum deformans and none with cerebral palsy produced the profile usually associated with conversion reaction, 36% of all profiles showed two scales above a T score of 70. This finding suggested that young adults with a physically disabling disease may be at higher risk for developing maladaptive personality traits.