Biomedical subjects

Keith D Horton

Publications and source records attributed to Keith D Horton.

3 recordsLinked to original sources

PubMed2006

Automatic retrieval in directed forgetting.

In two experiments, we investigated the role of automatic retrieval in directed forgetting, using a stem completion test. In each experiment, we compared the performance of an implicit group, a process dissociation procedure (PDP) group, and a group given a speeded response task. The response times of the speeded response group on the stem completion task replicated earlier data in suggesting that this group adopted a purely automatic retrieval strategy. Experiment 1 revealed a directed-forgetting effect on automatic retrieval with the item method, but Experiment 2 revealed no directed-forgetting effect on automatic retrieval with the list method, consistent with the lack of implicit effects with the list method throughout the literature. Both experiments showed lower automatic estimates for the PDP group than for the implicit and speeded response groups, which did not differ. The data are consistent with either a selective rehearsal or an inhibition account of directed forgetting with the list method. The comparison of methods for assessing automatic retrieval is consistent with earlier evidence suggesting that subjects may adopt a generate/recognize strategy when given direct retrieval instructions.

Automatism↗

PubMed2005

Measuring automatic retrieval: a comparison of implicit memory, process dissociation, and speeded response procedures.

Using the stem completion task, we compared estimates of automatic retrieval from an implicit memory task, the process dissociation procedure, and the speeded response procedure. Two standard manipulations were employed. In Experiment 1, a depth of processing effect was found on automatic retrieval using the speeded response procedure although this effect was substantially reduced in Experiment 2 when lexical processing was required of all words. In Experiment 3, the speeded response procedure showed an advantage of full versus divided attention at study on automatic retrieval. An implicit condition showed parallel effects in each study, suggesting that implicit stem completion may normally provide a good estimate of automatic retrieval. Also, we replicated earlier findings from the process dissociation procedure, but estimates of automatic retrieval from this procedure were consistently lower than those from the speeded response procedure, except when conscious retrieval was relatively low. We discuss several factors that may contribute to the conflicting outcomes, including the evidence for theoretical assumptions and criterial task differences between implicit and explicit tests.

Analysis of Variance↗

PubMed2002

Comparing techniques for estimating automatic retrieval: effects of retention interval.

Results from implicit memory (IM) tasks suggest that automatic retrieval remains stable or decreases over time. In contrast, results from the process dissociation approach (PDA) suggest that automatic retrieval may actually increase over time. One explanation for these discrepant results is that performance on IM tasks is contaminated by controlled retrieval strategies, thereby overestimating automatic retrieval, particularly at short retention intervals, when controlled retrieval strategies are high. An alternative explanation is that automatic and controlled retrieval are positively correlated, rather than independent as assumed by the PDA. If so, the PDA would underestimate automatic retrieval, particularly when controlled retrieval strategies are high. Results from a speeded IM task suggest that a standard IM task provided an accurate estimate of automatic retrieval, whereas the PDA underestimated automatic retrieval at a short retention interval. This pattern of underestimation by the PDA supports the conclusion that automatic and controlled retrieval were positively correlated rather than independent.

Automatism↗