Yoshiyuki Hosokai

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There is no consensus with regard to the clinical and neuroimaging characteristics of prodromal dementia in Parkinson's disease (PD). To delineate functional neuroimaging features of PD with mild cognitive impairment (PDMCI) and with no cognitive impairment (PDNC), we compared regional cerebral glucose metabolism (CMRglc) amongst 13 patients with PDMCI, 27(More)
Dementia is one of the most debilitating symptoms of Parkinson's disease. A recent longitudinal study suggests that up to 80% of patients with Parkinson's disease will eventually develop dementia. Despite its clinical importance, the development of dementia is still difficult to predict at early stages. We previously identified olfactory dysfunction as one(More)
Parkinson's disease is a common neurodegenerative disorder with both motor symptoms and cognitive deficits such as executive dysfunction. Over the past 100 years, a growing body of literature has suggested that patients with Parkinson's disease have characteristic personality traits such as industriousness, seriousness and inflexibility. They have also been(More)
Prader-Willi syndrome (PWS) is a genetically determined neurodevelopmental disorder presenting with behavioral symptoms including hyperphagia, disinhibition, and compulsive behavior. The behavioral problems in individuals with PWS are strikingly similar to those in patients with frontal pathologies, particularly those affecting the orbitofrontal cortex(More)
The attentional set-shifting deficit that has been observed in Parkinson's disease (PD) has long been considered neuropsychological evidence of the involvement of meso-prefrontal and prefrontal-striatal circuits in cognitive flexibility. However, recent studies have suggested that non-dopaminergic, posterior cortical pathologies may also contribute to this(More)
BACKGROUND Prader-Willi syndrome (PWS) is a genetically determined neurodevelopmental disorder and is generally regarded as a genetic model of obesity. Individuals with PWS exhibit behavioral symptoms including temper tantrums, rigid thinking, and compulsive behavior. The most striking feature of PWS is abnormal eating behavior, including hyperphagia,(More)
Hyposmia is one of the cardinal early symptoms of Parkinson disease (PD). Accumulating clinical and pathological evidence suggests that dysfunction of the olfactory-related cortices may be responsible for the impaired olfactory processing observed in PD; however, there are no clear data showing a direct association between altered brain metabolism and(More)
Idiopathic Parkinson's disease (PD) is associated with documented impairments in various visual functions. However, there have been only a limited number of studies that have reported on the brain regions responsible for impairment of visual recognition in PD. In our study, we evaluated the performance of PD patients and 24 healthy controls on the(More)
Language is fairly well preserved in most patients with mild Alzheimer's disease, but writing ability seems to be impaired even in the early stages of the disease. To investigate the neural bases of writing impairments in Alzheimer's disease (AD), we examined the correlation between writing ability and regional cerebral blood flow (rCBF) in 52 Japanese(More)
A patient developed frontal-lobe syndrome and psychotic symptoms after infarction in the pontomesencephalic junction. Stereotaxic lesion localization on magnetic resonance imaging and statistical analyses of regional cerebral blood flow (rCBF) disclosed an involvement of the rostral brainstem dopaminergic nuclei and hypoperfusion in the frontal-subcortical(More)