Peripheral dysgraphia: dissociations of lowercase from uppercase letters and of print from cursive writing.

Clinical analyses of patients with acquired dysgraphia provide unique opportunities to understand the cognitive and neural organization of written language production. We report J.B.

A comparison of letter and digit processing in letter-by-letter reading.

The extent to which letter-by-letter reading results from a specific orthographic deficit, as compared with a nonspecific disturbance in basic visuoperceptual mechanisms, is unclear. The current study directly compared processing of letters and digits in a letter-by-letter reader, G.M.

Progressive anomia without semantic or phonological impairment.

We describe a 59-year-old woman, M.T., with a progressive language impairment and neuroimaging findings of decreased perfusion (SPECT) and focal atrophy (MRI) in the left temporal region.

Preclinical vascular cognitive impairment and Alzheimer disease: neuropsychological test performance 5 years before diagnosis.

Background And Purpose: Neuropsychological changes that precede a diagnosis of vascular cognitive impairment (VCI) and the differences between preclinical VCI and Alzheimer disease (AD) are not well understood. We compared the neuropsychological performances of people with incident VCI, incident AD, and no cognitive impairment (NCI) 5 years before their clinical diagnoses.

Methods: The Canadian Study of Health and Aging is a prospective, cohort study of 10,263 randomly selected persons age 65 years or older.

Temporal processing deficits in letter-by-letter reading.

Theories of the cognitive impairment underlying letter-by-letter reading vary widely, including prelexical and lexical level deficits. One prominent prelexical account proposes that the disorder results from difficulty in processing multiple letters simultaneously. We investigated whether this deficit extends to letters presented in rapid temporal succession.

Disconnection of language and memory in semantic dementia: a comparative and theoretical analysis.

In this paper, we present an illustrative case of Semantic Dementia (SD) and we review the literature on this relatively rare progressive neurodegenerative disorder. After reviewing the clinical, neuroimaging, neuropathological, and genetic features of SD, we propose a theoretical framework that addresses features of SD and relates them to features of other well known neuropsychiatric syndromes. Our 'on-line / off-line disconnection' model seeks to conceptualize SD as a syndrome of disconnection between two large distributed cortical networks, namely, between those networks that subserve language function and those that subserve memory function.

Five-year outcomes for dementia defined solely by neuropsychological test performance.

Cognitive impairment that does not meet criteria for dementia is common and progresses to dementia at a high rate. It is not clear how best to define this type of cognitive impairment. We assessed the predictive validity of different case definitions for cognitive impairment and dementia by comparing rates of adverse outcomes for individuals who did not meet dementia criteria but had neuropsychological test results indicating dementia (NPDementia), those who had traditional dementia diagnoses (mild and moderate-severe severity), those who had other cognitive impairment but no dementia (CIND), and those with no cognitive impairment (NCI).

Neuropsychological predictors of incident dementia in patients with vascular cognitive impairment, without dementia.

Background: Vascular cognitive impairment that does not fulfill dementia criteria (ie, vascular cognitive impairment, no dementia [CIND]) is common. Although progression to dementia is frequent, little is known about factors that predict progression. We examined whether performance on neuropsychological tests administered at baseline could predict incident cases of dementia in patients with vascular CIND after 5 years.