Biomedical subjects

M L Chaves

Publications and source records attributed to M L Chaves.

4 recordsLinked to original sources

PubMed1992

Differential diagnosis between dementia and depression: a study of efficiency increment.

A battery of neuropsychological tests was examined to establish its value in differentiating mild dementia from depression. The battery was applied to 84 subjects: 31 dementia patients of several etiologies, 31 patients with major depression and 22 volunteers whose age and educational level was similar to that of the patients. The battery consisted of tests for immediate, recent and remote memory, the Mini Mental State examination, a screening test for language disorders, and tests measuring abstraction, calculation, judgement, praxic and gnosic functions. The results showed significant differences among the three groups in all memory tests. Deficits of abstraction, calculation, praxis and language functions were strongly associated with dementia. The epidemiological analysis of efficiency increment, with determination of sensitivity and specificity, showed a highly significant enhancement of efficiency for diagnostic purposes when the results of the tests were combined. These findings suggest that the entire battery of neuropsychological tests should be applied, and their results compared using the efficiency increment procedure, in order to establish a firm differential diagnosis between dementia and depression, and/or to detect the former when it is at a mild early stage.

Adult↗

PubMed1992

[Cognitive changes in workers at a data processing company].

A study of 191 data processing workers undertaken in Porto Alegre, Brazil, in 1989, is presented. The relationship between complaints of loss of memory and their respective scores on cognitive testing in three groups of workers, one with automatized repetitive activities and two others with diversified activities, is analysed. The scores and complaints are compared with the results of a screening test for psychiatric disorders in order to verify the influence of this confounding factor. No significant evidence of cognitive problems was found despite the high prevalence of complaints of memory loss in this population (65.4%). There is a significant statistical association between these complaints and the scores of the psychiatric testing. It is suggested that futures studies should emphasize psychiatric analysis with a view to clarifying the complaints of Data Processing workers.

Adult↗

PubMed1990

Diazepam inhibits retroactive interference of memory in humans: pretreatment with naltrexone does not alter this effect.

1. In a double-blind study of the effects of diazepam and naltrexone on retroactive memory interference, 88 healthy human volunteers were asked to study a text on the 1954 World Soccer Cup and were submitted to a written questionnaire on the material 48 h later. Three hours after reading the text, 58 of the subjects were exposed to a non-factual, derogatory comment on the World Cup. 2. All subjects were given either placebo or naltrexone (50 mg) before reading the text, and either placebo or diazepam (5 mg), per os, 2 h after reading the text (1 h prior to the comment). Subjects were assigned to the different treatment groups by a double-blind design. 3. Exposure to the derogatory comment caused retroactive memory interference with the retention of material from the text. Diazepam blocked the retroactive interference and had no effect of its own on retention of the text. Pretreatment with naltrexone did not influence retention, retrograde interference, or the effect of diazepam on these variables. 4. The results obtained here extend to healthy adult humans observations made on rats and mice in which diazepam blocked retroactive memory interference.

Adolescent↗

PubMed1990

The use of a new non-verbal test in the evaluation of recent memory.

A test for recent memory was developed using non-verbal material. The present report describes a series of experiments conducted to evaluate its reproducibility and the influences of changes in the interval between acquisition and retrieval, and age and level of instruction, and its sensitivity to the integrity of memory function. A total of 114 subjects participated in 5 experiments. The test of recent memory is reproducible over a period of at least 5 months and can be used with training-testing intervals of 24 to 48 h. The performance of the test is affected by age and level of instruction. Moreover, the memory test is sensitive to differences in the integrity of memory function. Thus, the memory test developed in this study may be used to evaluate the effects of behavioral and/or pharmacological manipulations on recent memory in homogeneous groups of subjects.

Adolescent↗