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Biomedical subjects

B Rypma

Publications and source records attributed to B Rypma.

4 recordsLinked to original sources
PubMed1991

Age and inhibition.

Two experiments assess adult age differences in the extent of inhibition or negative priming generated in a selective-attention task. Younger adults consistently demonstrated negative priming effects; they were slower to name a letter on a current trial that had served as a distractor on the previous trial relative to one that had not occurred on the previous trial. Whether or not inhibition dissipated when the response to stimulus interval was lengthened from 500 ms in Experiment 1 to 1,200 ms in Experiment 2 depended upon whether young subjects were aware of the patterns across trial types. Older adults did not show inhibition at either interval. The age effects are interpreted within the Hasher-Zacks (1988) framework, which proposes inhibition as a central mechanism determining the contents of working memory and consequently influencing a wide array of cognitive functions.

Adolescent↗
PubMed1988

Clinical stages of dementia and the dexamethasone suppression test.

1. This study was undertaken to evaluate the relationship between clinical aspects of primary degenerative dementia and suppression or non-suppression in the dexamethasone suppression test. 2. We studied 34 male patients with primary degenerative dementia (as diagnosed by DSM-III criteria). Dexamethasone 1 mg p.o. was administered at 11:00 PM and blood was drawn for cortisol determination at 4:00 PM the next day. 3. CLINICAL FACTORS INCLUDED: age, age at onset, duration of dementia, history of psychiatric illness, severity as measured by Global Deterioration Scale (GDS) score, and "malignancy" of dementia (rated by years of onset to institutionalization and as a ratio of Global Deterioration Scale to duration of primary degenerative dementia). 4. RESULTS: 56% of primary degenerative dementia patients failed to suppress. The highest degree of non-suppression was seen in Global Deterioration Scale 5 and 6 subjects (Table). 5. An unexpected finding was that a large number of Global Deterioration Scale 7 patients demonstrated normal post-dexamethasone suppression of the hypothalamic-pituitary-adrenal axis. 6. Some contradictions in previously reported studies may be explained by this pattern.

Aged↗