Is Huntington's disease associated with deficits in theory of mind?

OBJECTIVES: People with Huntington's disease (HD) can exhibit interpersonal difficulties and deficits in recognizing emotional facial expressions. We investigated whether individuals with HD exhibit impairments in the understanding of other people's mental states, an aspect of Theory of Mind (ToM). MATERIALS AND METHODS: Sixteen patients with HD and sixteen healthy controls completed two ToM tasks. One task involved recognising socially inappropriate behaviour and the other task required participants to judge complex mental states from photographs of people's eyes alone. To assess relationships between executive function and ToM, participants completed measures of verbal fluency, working memory and inhibition. The Problem Behaviours Assessment-short form (Neuropsychiatry Neuropsychol Behav Neurol, 14, 2001and 219) was completed twice using information from patients and their close relatives (where possible) to identify relationships between ToM impairment and behavioural problems. RESULTS: Patients with HD made significantly more errors on ToM tasks than controls, exhibiting difficulties in judging the social appropriateness of story character's behaviour and problems inferring complex mental states from photographs of people's eyes. Patients with HD also exhibited executive dysfunction. However, there was little evidence that executive impairments were related to ToM deficits. No correlations were apparent between problem behaviours and ToM errors. CONCLUSIONS: HD is associated with deficits in ToM. Furthermore, some of patients' ToM difficulties appear independent of executive dysfunction.

Thalamic deep brain stimulation for treatment-refractory Tourette syndrome: two-year outcome.

BACKGROUND: Eighteen patients with severe and refractory Tourette syndrome (TS) underwent bilateral thalamic deep brain stimulation (DBS). OBJECTIVE: To assess the long-term outcome on tics, behavioral symptoms, and cognitive functions in the largest case series of thalamic DBS for TS to date. METHODS: In this prospective cohort study, 15 of the original 18 patients were evaluated before and after surgery according to a standardized protocol that included both neuropsychiatric and neuropsychological assessments. RESULTS: In addition to marked reduction in tic severity (p = 0.001), 24-month follow-up ratings showed improvement in obsessive-compulsive symptoms (p = 0.009), anxiety symptoms (p = 0.001), depressive symptoms (p = 0.001), and subjective perception of social functioning/quality of life (p = 0.002) in 15 of 18 patients. There were no substantial differences on measures of cognitive functions before and after DBS. CONCLUSIONS: At 24-month follow-up, tic severity was improved in patients with intractable Tourette syndrome (TS) who underwent bilateral thalamic deep brain stimulation. Available data from 15 of 18 patients also showed that neuropsychiatric symptoms were improved and cognitive performances were not disadvantaged. Controlled studies on larger cohorts with blinded protocols are needed to verify that this procedure is effective and safe for selected patients with TS. LEVEL OF EVIDENCE: This study provides class IV evidence that bilateral thalamic deep brain stimulation reduces global tic severity measured 24 months after implantation in patients with severe intractable Tourette syndrome.

Huntington's disease patients show impaired perception of disgust in the gustatory and olfactory modalities.

Patients with Huntington's disease show deficits in recognizing disgust in the facial expressions and vocal intonations of others. In this study, the authors demonstrate that these disgust-related deficits extend to foul-smelling olfactory stimuli and inappropriate combinations of taste stimuli.

Systematic review of antidepressant therapies in Parkinson's disease.

Depression is the most common psychiatric disturbance in Parkinson's disease. We conducted a Cochrane systematic review to assess the efficacy and safety of antidepressant therapies in idiopathic Parkinson's disease. Relevant trials were identified from electronic databases, reference lists and queries to antidepressant manufacturers. Three randomised controlled trials examined oral antidepressants in 106 patients with Parkinson's disease. No eligible trials of electroconvulsive or behavioural therapy were found. In the first arm of the crossover trial by Andersen et al. (n=22), nortriptyline treated patients showed a larger improvement than placebo in a unique depression rating scale after 16 weeks although significance levels were not provided. A parallel group trial by Wermuth et al. (n=37) did not show any significant difference between citalopram and placebo in Hamilton score after 52 weeks. Rabey et al. (n=47) performed an open-label trial comparing fluvoxamine with amitriptyline. Similar numbers in each group had a 50% reduction in Hamilton score after 16 months. Major side effects including visual hallucinations and confusion were reported with fluvoxamine and amitriptyline. Insufficient data on the effectiveness and safety of antidepressant therapies in Parkinson's disease are available on which to make recommendations for their use. Large scale randomised controlled trials are urgently required.

Proprioceptive sensory function in Parkinson's disease and Huntington's disease: evidence from proprioception-related EEG potentials.

In both Parkinson's disease and Huntington's disease, proprioceptive sensory deficits have been suggested to contribute to the motor manifestations of the disease. Here, proprioceptive sensory function was investigated in Parkinson's disease patients, Huntington's disease patients, and healthy control subjects (each group n=8), using proprioception-related evoked potentials. Proprioception-related potentials were elicited by passive index finger movements and measured with high-density EEG. Conventional median nerve somatosensory evoked potentials (mnSEPs) were recorded in the same session. Analysis included amplitude and latency measures from selected scalp electrodes and dipole source reconstruction. We found a proprioception-related N90 component of normal latency in both Parkinson's disease and Huntington's disease. The source strength of the underlying cortical generator was normal in Parkinson's disease, but marginally reduced in Huntington's disease. Using the source location of the N20-P20 component of the mnSEP as a landmark for postcentral area 3b, the N90 was localized to the precentral motor cortex. At a latency around 170-180 ms proprioception-related potentials were explained by bilateral sensory cortex activation with an altered distribution in Parkinson's disease and a reduction of ipsilateral activation in Huntington's disease. Together, the results show largely normal early proprioception-related potentials, but changes in the cortical processing of kinaesthetic signals at longer latencies in both diseases.

Catatonia. 2: Diagnosis, management and prognosis.

This is the second of two articles reviewing catatonia. In the first, catatonia was described as an under-recognized syndrome with a potentially fatal outcome. It was suggested that treatment with neuroleptics may exacerbate the syndrome. The differential diagnosis, management and prognosis of catatonia are reviewed below.

Catatonia. 1: History and clinical features.

Catatonia is commonly encountered in psychiatric and medical practice but is under-recognized. It occurs in association with a wide range of disorders and drugs. Psychiatric education and textbooks mistakenly only consider catatonia as a subtype of schizophrenia. This article, the first of two, reviews the development of the concept of catatonia, its epidemiology, clinical features and pathophysiology.

Vomiting and retching in Gilles de la Tourette syndrome: a report of ten cases and a review of the literature.

Retching and vomiting are common symptoms in childhood. We describe the cases of 10 patients with Gilles de la Tourette syndrome (GTS) for whom vomiting or retching tics were part of the clinical picture, and discuss other instances where retching and vomiting occur with neuropsychiatric or movement disorders.

Postprandial changes in superoxide dismutase activity in subjects with Gilles de la Tourette syndrome and controls.

Erythrocyte measures of copper-zinc superoxide dismutase (CuZnSOD) were performed on 11 subjects with a clinical diagnosis of Gilles de la Tourette syndrome (GTS) and 6 healthy controls at specified intervals throughout the day. There were no significant differences between GTS subjects and controls but in both subjects and controls there was a significant increase in SOD, 75 min postprandially, which decreased to baseline 135 min postprandially. This has implications for the timing of biological samples in future studies of SOD. Possible reasons for the increase are discussed.