Parkinsonism & related disorders
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Parkinsonism Relat. Disord. · Jun 2015
Pareidolia in Parkinson's disease without dementia: A positron emission tomography study.
Pareidolia, which is a particular type of complex visual illusion, has been reported to be a phenomenon analogous to visual hallucinations in patients with dementia with Lewy bodies. However, whether pareidolia is observed in Parkinson's disease (PD) or whether there are common underlying mechanisms of these two types of visual misperceptions remains to be elucidated. ⋯ Our study suggests that PD patients without dementia experience pareidolia more frequently than healthy controls and that posterior cortical dysfunction could be a common neural mechanism of pareidolia and visual hallucinations. Pareidolia could represent subclinical hallucinations or a predisposition to visual hallucinations in Lewy body disease.
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Parkinsonism Relat. Disord. · May 2015
Randomized Controlled TrialDopaminergic denervation severity depends on COMT Val158Met polymorphism in Parkinson's disease.
Catecholamine-O-methyl-tranferase (COMT) initiates dopamine degradation. Its activity is mainly determined by a single nucleotide polymorphism in the COMT gene (Val158Met, rs4680) separating high (Val/Val, COMT(HH)), intermediate (Val/Met, COMT(HL)) and low metabolizers (Met/Met, COMT(LL)). We investigated dopaminergic denervation in the striatum in PD patients according to COMT rs4680 genotype. ⋯ Striatal denervation differs according to COMT-Val158Met polymorphism. COMT activity may play a role as a compensatory mechanism in PD motor symptoms.
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Parkinsonism Relat. Disord. · May 2015
Editorial Biography Historical ArticleIn memoriam: Paul J. Bedard, MD PhD (1942-2014).
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Parkinsonism Relat. Disord. · May 2015
Apathy and striatal dopamine transporter levels in de-novo, untreated Parkinson's disease patients.
Apathy is a neuropsychiatric symptom in Parkinson's Disease (PD) which has a negative impact on quality of life and might be related in part to damage of presynaptic dopaminergic system. Little is known about relationship between striatal dopamine levels and apathy in PD patients without dementia and/or depression. The aim of the present study was to investigate the relationship between "pure apathy" and striatal dopamine uptake in untreated, drug-naïve PD patients without clinically significant dementia and/or depression. ⋯ Apathy is associated with reduced striatal dopamine transporter levels, independent of motor disability and depression in non-demented PD patients. These findings suggest that dysfunction of dopaminergic innervation in the striatum and particularly in the right caudate may contribute to development of apathy in early PD.
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Parkinsonism Relat. Disord. · May 2015
Diffusion tensor imaging and tract-based spatial statistics analysis in Friedreich's ataxia patients.
Friedreich's ataxia (FRDA) is the most common hereditary ataxia and thinning of the cervical spinal cord is a consistent observation in Magnetic resonance imaging (MRI), although neuropathological examination in FRDA reveals neuronal loss in gray matter (GM) nuclei and degeneration of white matter (WM) tracts in the spinal cord, brainstem and cerebellum. Using diffusion-tensor (DTI) imaging and tract-based spatial statistics (TBSS) we tested the hypothesis that WM damage in FRDA is more extensive than previously described and probably involves normal-appearing WM. ⋯ DTI and TBSS techniques clearly demonstrate the extensive cerebral and cerebellar involvement in FRDA, partially explaining the clinical phenotype of the disease. Further studies are needed with larger samples to correlate clinical, genetic findings and ataxia scores.