Assessment of semantic processing in patients with Alzheimer's type dementia: The release-of-proactive-inhibition paradigm.

Abstract

This study investigated memory functioning in patients with dementia of Alzheimer's type by using the release-from-proactive-interference paradigm. Two fivelist series of words were presented, one with a shift (on the last list of the series) in the taxonomic category (semantic condition) of the presented items, and one with a shift in the rhyming category (acoustic condition). Subjects were 10 patients who met clinical research criteria for probable dementia of Alzheimer's type and 20 matched normal controls. Across conditions, Alzheimer's patients exhibited lower correct recall and higher intrusion rates than did normal controls. More important, the Alzheimer's patients did not show the expected build-up and release from proactive interference when correct recall was considered, but they did show the expected pattern when intrusion rate was considered. Normal controls showed evidence of semantic processing on both measures. These results are discussed in relation to the defects in semantic memory hypothesized in Alzheimer's disease.

An Evaluation of Deficits in Semantic Cueing and Proactive and Retroactive Interference as Early Features of Alzheimer's Disease

“…Other investigations have shown the presence of PI in mild AD patients (21, 22,23, 24, 25). In contrast, other studies evaluating the build-up and release from PI have suggested lack of PI effects (26, 27) or even less vulnerability to PI (28) in AD patients as compared to cognitively normal subjects or Parkinson disease subjects (29, 30). It has been suggested that sufficient global memory impairment in certain AD groups may simply preclude the detection of semantic interference effect in this population.…”

Semantic interference deficits and the detection of mild Alzheimer's disease and mild cognitive impairment without dementia

“…The subsequent presentation of a dissimilar list should theoretically result in a recovery of performance (i.e., release from proactive interference). However, studies on build-up and release from proactive interference with AD patients have been mixed (Bellenville et al, 1992;Binnetti et al, 1995;Cushman et al, 1988). A potential limitation of these paradigms in AD is that deficits in initial encoding and recall for items presented for only one trial may result in floor effects, making it difficult to evaluate decrements in recall when other semantically related targets are presented.…”

Encoding processes in social anxiety

“…oXner, Rockstroh, Cohen, Wagner, & Elbert, 1999) with various patient populations. Whereas a number of experiments that used patients with dementia failed to show PI and RPI (e.g., Belleville et al, 1992), other studies involving patients with schizophrenia did report RPI effects (Traupmann, Berzofsky, & Kesselman, 1976). These effects have previously been interpreted as evidence to suggest that individuals encode the attributes of the word category in memory, and that decreased recall performance is not the result of an encoding deficiency (Traupmann et al, 1976).…”

“…The phenomenon of release of PI has also been examined in other fields of psychology, including developmental psychology (e.g., Bjorklund, Smith, & Ornstein, 1982;Dobbs, Aubrey, & Rule, 1989) and neuropsychology (e.g., Belleville et al, 1992;Binetti et al, 1996;R . oXner, Rockstroh, Cohen, Wagner, & Elbert, 1999) with various patient populations.…”

“…The absence of RPI effects seems to imply that the encoding dimensions in question were irrelevant for semantic processing (Wickens, 1972). In studies examining individual differences, a lack of RPI is typically attributed to a semantic encoding deficit (e.g., Belleville et al, 1992).…”