PubMed HealthSearch

Biomedical subjects

G W Rebok

Publications and source records attributed to G W Rebok.

6 recordsLinked to original sources

Developmental epidemiologically based preventive trials: baseline modeling of early target behaviors and depressive symptoms.

Describes a conceptual framework for identifying and targeting developmental antecedents in early childhood that have been shown in previous work to predict delinquency and violent behavior, heavy drug use, depression, and other psychiatric symptoms and possibly disorders in late adolescence and into adulthood. Criteria are described that guided choices of targets for two epidemiologically based, randomized preventive trials carried out in 19 elementary schools in the eastern half of Baltimore, involving more than 2,400 first-grade children over the course of first and second grades. Baseline models derived from the first of two cohorts show the evolving patterns of concurrence among the target antecedents. The central role of concentration problems emerged. From Fall to Spring in first grade, concentration problems led to shy and aggressive behavior and poor achievement in both genders and to depressive symptoms among girls. There was evidence for reciprocal relationships in girls. For example, depressive symptoms led to poor achievement in both girls and boys, whereas poor achievement led to depressive symptoms in girls but not boys, at least over the first-grade year. These results provide important epidemiological data relevant to the developmental paths leading to the problem outcomes and suggest preventive trials.

Adolescent

Long-term retention of implicit learning in Huntington's disease.

Implicit learning was examined in 15 Huntington's disease (HD) patients and 15 control subjects (NC) using a semantic decision-making task. HD patients demonstrated only slightly reduced priming; like NC subjects, their decision times decreased over repeated presentations, though to a somewhat lesser degree. On explicit recognition testing, the HD group made significantly more false positive errors than did the control group, suggesting an impairment of effortful retrieval. The groups displayed equivalent retention of implicitly learned material after 6 months. The striatal neuronal loss of early Huntington's disease does not markedly affect priming or retention of primed stimuli, but may alter explicit memory judgements.

Adult

Dimensional preferences in middle and old age.

Dimensional preferences in 40 middle-aged (M = 41.62 years) and 40 elderly (M = 72.22 years) females were assessed using a dimensional choice task. Significant age differences in reaction times of choice but not in number of dimensional choices were obtained. There was a perfect rank-order correspondence between the two age groups in dimensional choices with form being the most preferred and color the least preferred perceptual dimension.

Adult

Effects of varying irrelevant information on adult age differences in problem solving.

Sixty young (M = 20.6), middle-aged (M = 52.4), and elderly (M = 72.6) men and women solved problems which required them to match one of two stimulus arrays to a standard. On each problem one dimension (color, form, number, or position) was relevant to correct matching, and three dimensions, which were either variable or constant, were irrelevant to solution. Age and the number of variable irrelevant dimensions were the best predictors of reaction time and error scores. Young were significantly faster than middle-aged and the middle-aged were faster than the elderly. The elderly made most errors, but the young and middle-aged were not significantly different from each other. Reaction times and errors increased as the number of variable irrelevant dimensions increased. For the elderly there was a disproportionate increase in both reaction times and errors as levels of irrelevancy increased. No reliable differences were found with regard to gender. The results were discussed in terms of an age-related decline in the ability to ignore irrelevant information.

Adult