Biomedical subjects

L Bernardin

Publications and source records attributed to L Bernardin.

6 recordsLinked to original sources

PubMed1991

Automatic memory processes in patients with multiple sclerosis.

To better understand the nature of the memory deficit in patients with multiple sclerosis, we designed a study to compare automatic vs effortful memory processes. Forty-one patients with definite multiple sclerosis and 45 demographically matched normal control subjects were administered two tasks designed to assess both automatic (monitoring frequency and modality) and effortful (free and cued-recall) processing. Results indicated that patients with multiple sclerosis, as expected, were significantly impaired on memory measures requiring effort, but performed normally on automatic measures. Performance on the memory indexes did not correlate with self-reported depression. The implications of these findings for delineating the locus of the memory impairment in multiple sclerosis is discussed.

Adult↗

PubMed1991

Cognitive dysfunction in multiple sclerosis. I. Frequency, patterns, and prediction.

Previous frequency estimates of cognitive dysfunction in multiple sclerosis have ranged from 54 to 65 percent. These studies may overestimate the frequency in the general MS population, since the patients in these studies were recruited from clinic populations. In the present study, we administered a comprehensive neuropsychological test battery to 100 community-based MS patients and 100 demographically matched healthy controls. Of 31 cognitive test indices examined, 48 MS patients and five controls were impaired on four or more test indices, yielding an overall frequency rate of 43% for the MS group. The pattern of cognitive decline was not uniform: MS patients were more frequently impaired on measures of recent memory, sustained attention, verbal fluency, conceptual reasoning, and visuospatial perception, and less frequently impaired on measures of language and immediate and remote memory. We developed a brief (20-minute) screening battery empirically by selecting the four most sensitive test indices from the comprehensive battery. The brief battery yielded a sensitivity value of 71% and a specificity value of 94% in discriminating cognitively intact from impaired MS patients, as defined by the comprehensive battery. Cognitive impairment was not significantly associated with illness duration, depression, disease course, or medication usage, but was significantly (albeit weakly) correlated with physical disability.

Adult↗

PubMed1991

Cognitive dysfunction in multiple sclerosis. II. Impact on employment and social functioning.

We designed a study to assess the specific contribution of cognitive dysfunction to multiple sclerosis patients' problems in daily living. Based on the results of a comprehensive neuropsychological test battery, we classified 100 MS patients as either cognitively intact (N = 52) or cognitively impaired (N = 48). In addition to a neurologic examination, MS patients completed questionnaires on mood and social functioning, underwent a comprehensive in-home occupational therapy evaluation, and were rated by a close relative or friend regarding specific personality characteristics. While there were no significant differences between the two groups on measures of physical disability and illness duration, patients in the cognitively impaired group were less likely to be working, engaged in fewer social and avocational activities, reported more sexual dysfunction, experienced greater difficulty in performing routine household tasks, and exhibited more psychopathology than cognitively intact patients. These findings suggest that cognitive dysfunction is a major factor in determining the quality of life of patients with MS.

Activities of Daily Living↗

PubMed1989

Neuropsychological test findings in subjects with leukoaraiosis.

Focal periventricular white-matter changes (leukoaraiosis) have been identified incidentally on brain imaging in normal healthy individuals and more commonly in the elderly and in hypertensive individuals. It has been suggested that leukoaraiosis represents the early stages of Binswanger's leukoencephalopathy, a dementing process thought to be related to hypertensive cerebrovascular disease. To test this hypothesis, extensive neuropsychological tests were administered to 50 consecutive normotensive, middle-aged, healthy volunteers. Ten subjects (20%) had white-matter changes on magnetic resonance scans; 40 subjects (80%) had normal scans. The differences observed on neuropsychological testing between subjects with and without leukoaraiosis were not significant. While this study argues against a link between leukoaraiosis and dementia, prospective longitudinal studies are needed to determine the value of leukoaraiosis in predicting future cognitive decline.

Adult↗

PubMed1989

Cerebral disconnection in multiple sclerosis. Relationship to atrophy of the corpus callosum.

Left ear suppression to dichotically presented verbal stimuli has been observed in patients with multiple sclerosis (MS). Rubens and coworkers have suggested that a disconnection of the auditory callosal pathways may account for this finding. To examine this proposal, we compared the performance of 28 MS patients with significant corpus callosum atrophy (CCA) on midsagittal magnetic resonance scans, 16 MS patients without significant CCA, and 64 demographically matched normal control subjects on two laterality tasks: verbal dichotic listening (consonant-vowel syllables) and tachistiscopic object-naming latency. Results indicated that left ear suppression was found only in the MS patients with CCA. Likewise, patients in the MS group with CCA were slow in responding to stimuli presented in the left visual field; this effect was not observed in patients without CCA. These findings support the hypothesis that efficiency of cross-callosal information flow is reduced in MS patients with CCA.

Adult↗

PubMed1989

Correlation of magnetic resonance imaging with neuropsychological testing in multiple sclerosis.

Previous research has suggested that cerebral lesions observed on magnetic resonance imaging (MRI) of MS patients are clinically "silent." We examined the validity of this assertion by correlating neuropsychological test performance with MRI findings in 53 MS patients. We used a semiautomated quantitation system to measure three MRI variables: total lesion area (TLA), ventricular-brain ratio (VBR), and size of the corpus callosum (SCC). Stepwise multiple regression analyses indicated that TLA was a robust predictor of cognitive dysfunction, particularly for measures of recent memory, abstract/conceptual reasoning, language, and visuospatial problem solving. SCC predicted test performance on measures on mental processing speed and rapid problem solving, while VBR did not independently predict cognitive test findings. These findings suggest that cerebral lesions in MS produce cognitive dysfunction and that MRI may be a useful predictor of cognitive dysfunction.

Brain↗