Biomedical subjects

H Buschke

Publications and source records attributed to H Buschke.

11 recordsLinked to original sources

PubMed1992

Implicit and explicit memory in young, old, and demented adults.

Previous study of scopolamine and memory (Grober et al., 1989) showed that young adults given moderate or high doses of scopolamine maintained maximum cued recall in spite of a dose-dependent decrement in free recall when memory was assessed by cued selective reminding (CSR), a procedure which circumvents inattention and induces semantic processing. Intact recall by CSR indicates either that scopolamine impairs memory indirectly through effects on attention and information processing or that it impairs explicit memory but not implicit memory. In the present study which was done to determine if CSR reflects explicit or implicit memory, a free association test was used to estimate implicit memory after CSR was administered; explicit memory was estimated with a final trial of cued recall. Data from young, nondemented, and demented adults indicate that CSR reflects explicit memory supporting the interpretation of the previous study that scopolamine does not produce direct impairment of explicit memory.

Adolescent↗

PubMed1988

Screening for dementia by memory testing.

Enhanced cued recall provides a simple and clinically useful memory test for identifying dementia in the elderly. Because this test induces semantic processing and coordinates encoding and retrieval for maximum recall, genuine memory deficits due to impairment of specific memory processes can be distinguished from apparent memory deficits due to use of inefficient strategies or impairment of other cognitive processes. Since genuine memory deficits in the elderly are usually associated with dementia, their identification is highly predictive of clinical dementia. The present study validates the use of enhanced cued recall as a screening test for dementia in 70 aged subjects. All but one person with a pure amnesia were correctly classified. Enhanced cued recall correctly classified 97% of the 120 subjects in this and the previous study. Enhanced cued recall shows learning not revealed by free recall, providing more accurate measurement of memory, and distinguishes demented from nondemented elderly more accurately than either free recall or recognition.

Aged↗

PubMed1985

Impaired ranking of semantic attributes in dementia.

The present work explored the loss of semantic attributes that is said to occur in dementia. In the first two experiments, subjects had to select attributes that went with concepts like airplane and church. The finding that demented subjects maintained high levels of accuracy when selecting attributes suggested that the semantic content of their concepts was relatively well preserved. The organization of the content was explored in a third experiment by having subjects order attributes according to their relative importance in defining concepts. While demented subjects performed better than chance, they did not rank attributes as well as healthy aged subjects, suggesting a disruption in organization whereby the importance of central attributes is reduced. The hypothesized disruption in organization is viewed in relation to the learning and memory deficit that is the hallmark of the dementias.

Aged↗

PubMed1984

Cued recall in amnesia.

Use of a search procedure to control processing during learning results in apparently normal cued recall by some amnesic patients with impaired free-recall learning. This suggests that their ability to encode and retrieve may be relatively intact when they are induced to carry out effective processing during learning. When processing is controlled during learning, cued recall should be useful for neuropsychological evaluation of residual learning and memory capacity.

Aged↗

PubMed1983

Age differences in cognitive effort in recall.

A secondary task methodology was used to investigate age differences in the amount of cognitive effort demanded by free recall. Aged and young adults performed a reaction time task while simultaneously retrieving a list of items in multitrial free-recall learning. RTs were slower in aged than young adults on each trial, suggesting that free recall is more demanding for older persons. In addition, the secondary task did not interfere with recall by older adults, suggesting that this technique is feasible in older persons. These results are consistent with the cognitive-effort hypotheses which postulate age differences in the demands of memory processing to be one factor underlying age-related deficits. An additional finding suggested that age differences in retrieval effort may also be related to differences in list organization.

Adolescent↗

PubMed1975