Posterior cortical atrophy with prominent alexia without agraphia in a Tourette syndrome.

We report for the first time a patient with childhood-onset Tourette's syndrome (TS) who developed alexia without agraphia, acalculia, visual agnosia for objects and faces, and preserved mnesic functions in older age. Neuroimaging studies demonstrated temporo-parieto-occipital cortical atrophy and fronto-temporo-parieto-occipital hypometabolism, both more prominent on the left side. This case fulfils the diagnostic criteria of posterior cortical atrophy (PCA). The possible link between TS and PCA is discussed.

Frontal dysfunction contributes to the genesis of hallucinations in non-demented Parkinsonian patients.

BACKGROUND: Hallucinations occur in patients with Parkinson's disease (PD) with reported prevalence ranging from 8% to 40%. Hallucinations are significantly associated with dementia in PD, but little is known about possible distinctive cognitive features of non-demented PD patients who develop hallucinations. OBJECTIVE: The aim of the study was to assess selected cognitive abilities in non-demented PD patients with and without hallucinations in order to identify specific neuropsychological correlates of such phenomena. METHODS: Forty-eight consecutive patients with PD and Mini Mental State Examination (MMSE) > or = 23 were examined for the presence of hallucinations and assessed on standardized neuropsychological tasks for semantic and phonological fluency, verbal learning and logical abstract thinking; disease severity was staged according to Hoehn and Yahr scale. RESULTS: Fourteen (29.2%) of 48 patients experienced hallucinations. There was no difference between hallucinators and non-hallucinators on demographic variables, disease severity and dose of any pharmacological treatment. Disease duration was significantly longer in hallucinator vs non-hallucinator patients (p = 0.02). Patients with hallucinations scored significantly lower than patients without hallucinations only on verbal learning-immediate recall task (p = 0.0324), and semantic and phonological fluency tasks (p = 0.0005 and p = 0.0036, respectively). CONCLUSIONS: Our results suggest that PD patients with hallucinations show reduced performance on tasks that explore executive functioning as compared with non-hallucinators. Therefore, executive dysfunction may be considered as a risk factor for the development of hallucinations in non-demented PD patients.

Do visuospatial and constructional disturbances differentiate frontal variant of frontotemporal dementia and Alzheimer's disease? an experimental study of a clinical belief.

BACKGROUND: In recent years several attempts have been made to distinguish frontotemporal dementia (FTD) from Alzheimer's disease (AD) on neuropsychological grounds; in particular, it has been suggested that FTD patients show spared spatial abilities with respect to AD patients. OBJECTIVE: We aimed at verifying whether patients with the frontal variant of frontotemporal dementia (fv-FTD) and AD patients perform differently on visuospatial and constructional tasks. METHODS: We assessed a wide range of visuospatial abilities and provided a qualitative analysis of constructional performances in 14 fv-FTD patients and 11 AD patients, matched for general cognitive abilities. RESULTS: The two groups of patients achieved similar scores on two copying tasks, presented similar drawing procedures in copying Rey complex figure and made a similar quantitative and qualitative pattern of errors in copying simple geometrical drawings. Moreover, no significant difference was found between fv-FTD and AD patients on a specific battery for visuospatial abilities. CONCLUSIONS: Our data and a review of the literature suggest that basic visuospatial and constructional skills cannot be taken as a reliable diagnostic criterion for distinguishing fv-FTD and AD at a mild to moderate disease stage and that the clinical belief of spared spatial abilities in fv-FTD has to be referred to the lack of topographic disorientation in comparison to AD.