Biomedical subjects

R J Frerichs

Publications and source records attributed to R J Frerichs.

3 recordsLinked to original sources

PubMed2001

Cognitive impairment, no dementia: concepts and issues.

This article reviews the concept of mild cognitive impairment in groups of people whose cognitive impairment does not warrant a diagnosis of dementia (cognitive impairment, no dementia; CIND). Problems with the application of existing sets of criteria to the Canadian Study of Health and Aging (CSHA) data sets are addressed and a procedure for identifying a subgroup presumed "at risk" for developing dementia is presented. Application of an informant's report of changes in cognitive functioning and neuropsychologists' ratings of mild to severe deficits in any of eight cognitive domains results in approximately half of the CIND cases being identified as "at risk." The rationale for the collection of specific information related to CIND in CSHA-2 is provided. A minority of people identified with CIND at CSHA-2 showed only memory impairment, and most demonstrated cognitive loss over the preceding five-year interval. This article provides a conceptual basis for procedures to identify people with cognitive impairment most likely to decline to dementia.

Activities of Daily Living↗

PubMed2000

Cognitive impairment with no dementia (CIND): longitudinal studies, the findings, and the issues.

Identification of persons at risk for developing dementia is of increasing importance as the proportion of persons over the age of 65 years grows globally. This review examines the neuropsychological literature specifically addressing the concept of impaired cognitive functioning of insufficient magnitude to warrant a diagnosis of dementia and its meaning with respect to the development of dementia. Although the most obvious finding in the literature is that persons with impaired cognitive functioning have varied outcomes, it is clear that a significant proportion of persons with mild cognitive impairment progress to dementia over a 1- to 2-year interval and approximately 50% progress to dementia by 5 years. The best and most commonly identified predictors of decline to dementia include age and lower baseline performance on neuropsychological measures (e.g., measures of memory). In discussing these findings, issues related to sample definition, sample selection, and methodology are identified and recommendations for future research are provided.

Aged↗

PubMed1999

Visual localization in dyslexia.

Individuals with specific reading disability (SRD) may exhibit visual psychophysical abnormalities that include prolonged visual persistence, decreased luminance contrast sensitivity, lower flicker fusion thresholds, abnormal metacontrast masking, and lower motion detection sensitivity. These abnormalities could result from impairment of the magnocellular division of the visual afferent pathway to the cortex. The authors predicted that an impairment of this pathway would also cause abnormalities in ability to localize visual stimuli. This prediction was tested in 2 experiments. Results of both experiments showed that adults who reported a history of SRD and who currently had lower reading performance were less able than non-SRD participants to report the locations of small visual stimuli that were briefly flashed at positions similar to the ends of lines of text.

Adult↗