Joan M. Swearer

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The amyloid cascade hypothesis suggests that the aggregation and deposition of amyloid-beta protein is an initiating event in Alzheimer's disease (AD). Using amyloid imaging technology, such as the positron emission tomography (PET) agent Pittsburgh compound-B (PiB), it is possible to explore the natural history of preclinical amyloid deposition in people(More)
The functional properties and topographic distribution of event-related potential (ERP) components elicited by visual discrimination of orientation, spatial frequency, spatial location, and color were investigated. ERPs were recorded from 28 electrode sites from 16 adult subjects. Five ERP components were measured: N1 (peak latency = 160 ms), P2 (250 ms),(More)
Alzheimer's disease (AD) is caused by multiple genetic and/or environmental etiologies. Because differences in the genetically determined pathogenesis may cause differences in the phenotype, we examined age at onset and age at death in 90 subjects with dominantly inherited AD due to different mutations (amyloid precursor protein, presenilin-1, and(More)
The relationship of P3 latency of the event-related potential (ERP) to psychometric performance was investigated in 41 subjects who ranged in age from 20 to 88 years. P3 responses were recorded from subjects using an auditory oddball paradigm with and without task-demands. Subjects also received psychometric tests of verbal performance, visuospatial(More)
Whether all etiologic forms of Alzheimer's disease (AD) share a final common pathway is a major issue. We determined the severity and regional distribution of neuronal loss, amyloid plaques, neuritic plaques (NPs), and neurofibrillary tangles (NFTs), and calculated the ratio of neuronal loss to NPs and NFTs in brains of 19 familial AD (FAD) patients with(More)
CSF amyloid beta-peptide 42 (Abeta42) levels in presymptomatic subjects with pathogenic mutations in the PS1 gene are significantly lower than in an age-matched control group. Consequently, in these subjects, there is a window of opportunity estimated as at least 4 to 12 years to evaluate the ability of any putative prophylactic therapy to decrease, arrest,(More)
OBJECTIVE The purpose of this study was to evaluate the performance of patients with schizophrenia on tests of visual discrimination and recognition of different stimulus features. METHOD Thirteen medicated male schizophrenic patients and 13 normal comparison subjects were tested on four stimulus features: spatial frequency, pattern, location, and(More)
Clinical features at the initial examination of 42 patients with probable Alzheimer's disease were tested for prognostic value at subsequent follow-up of 54 +/- 25 months. These potential prognostic features were of three types: degree of severity features (eg, IQ scores); variable clinical features (eg, extrapyramidal signs); and individual distinguishing(More)
Amyotrophic lateral sclerosis (ALS) is classically described as a pure motor disease; however, there is growing evidence of a range of cognitive impairment. Cognitive abnormalities include deficiencies in frontal executive skills, varying from mild deficits to meeting criteria for diagnosis of frontotemporal dementia (FTD). Cognitive impairment occurs in(More)
The exact nature of the relationship between Lewy body disease and Alzheimer's disease (AD) is unknown. To investigate this, we compared cases of pure Lewy body disease, mixed Lewy body disease with AD, and pure AD to see what pathological features were shared and how they differed. We counted neurons, Lewy bodies, diffuse and neuritic senile plaques,(More)