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H L Roediger

Publications and source records attributed to H L Roediger.

11 recordsLinked to original sources
PubMed1992

Depression and implicit memory: a commentary.

In this invited commentary, we review four studies in which the issue of whether depression affects priming on implicit memory tests was examined. We conclude that a depressive mood does not affect amount of priming on several implicit memory tests under conditions in which marked effects are shown on conscious recollection (explicit memory). The mood congruity effect (depressives remember depression-related words better than controls; controls remember other types of material better than depressives) also largely disappears on perceptual implicit memory tests. We speculate about reasons for discrepancies in the literature, relate the findings to some current theories of individual differences in memory, and suggest some directions for future research.

Affect↗
PubMed1992

Effects of exact repetition and conceptual repetition on free recall and primed word-fragment completion.

Experiments are reported in which effects of repeating words exactly (e.g., elephant, elephant) or repeating some meaningful aspect--a synonym (pachyderm), an associate (tusk), or a category coordinate (hippopotamus)--were examined on free recall and word-fragment completion. In free recall, large effects of both exact repetition and conceptual repetition were found; the magnitude of the latter was about half that of the former. In contrast, in primed word-fragment completion, repetition effects were rather small and there was no evidence of indirect (or conceptual) priming. Also, presentation of synonyms, associates, and coordinates in isolation failed to prime word-fragment completion. The results provide further evidence that the basis of primed word-fragment completion is different from that of free recall; the former seems to have a perceptual (or perhaps lexical) basis, whereas the latter relies more on meaningful processing.

Adult↗
PubMed1992

Direct comparison of two implicit memory tests: word fragment and word stem completion.

In 3 experiments, the implicit memory tests of word fragment and word stem completion showed comparable effects over several variables: Study of words produced more priming than did study of pictures, no levels-of-processing effect occurred for words, more priming was obtained from pictures when Ss imaged the pictures' names than when they rated them for pleasantness, and forgetting rates were generally similar for the tests. A different pattern of results for the first 3 variables occurred under explicit test conditions with the same word fragments or word stems as cues. We conclude that the 2 implicit tests are measuring a similar form of perceptual memory. Furthermore, we argue that both tests are truly implicit because they meet Schacter, Bowers, & Booker's (1989) retrieval intentionality criterion: Levels of processing of words have a powerful effect on explicit versions of the tests but no effect on implicit versions.

Adult↗
PubMed1992

The role of syllabic and orthographic properties of letter cues in solving word fragments.

The present research examined the role of phonological and orthographic properties of cues in mediating the retrieval of words from the mental lexicon. The task required subjects to resolve fragmented words when provided with semantically related cues (e.g., spiteful:---DIC----). Phonological properties of the letter cues were manipulated such that the letters either corresponded to the syllables (e.g., DIC in vindictive) or nonsyllables (NDI) in the word. Orthographic properties of the letter cues were manipulated by selecting letter groups that either co-occurred frequently in the language or did not. In two experiments, results revealed little or no effect of the phonological variable (syllables) but a reliable effect of the orthographic variable (letter-cue frequency). Letter cues with a low frequency of co-occurrence in the language led to better completion of the fragmented words. We interpret these findings as support for models of lexical representation that are based on orthographic properties (e.g., Seidenberg & McClelland, 1989) rather than those based on phonological constraints.

Adult↗
PubMed1990

Implicit memory. Retention without remembering.

Explicit measures of human memory, such as recall or recognition, reflect conscious recollection of the past. Implicit tests of retention measure transfer (or priming) from past experience on tasks that do not require conscious recollection of recent experiences for their performance. The article reviews research on the relation between explicit and implicit memory. The evidence points to substantial differences between standard explicit and implicit tests, because many variables create dissociations between these tests. For example, although pictures are remembered better than words on explicit tests, words produce more priming than do pictures on several implicit tests. These dissociations may implicate different memory systems that subserve distinct memorial functions, but the present argument is that many dissociations can be understood by appealing to general principles that apply to both explicit and implicit tests. Phenomena studied under the rubric of implicit memory may have important implications in many other fields, including social cognition, problem solving, and cognitive development.

Amnesia↗
PubMed1990

Specifying criteria for postulating memory systems.

We have examined four criteria commonly used to distinguish separate memory systems: functional dissociation, independent neural systems, stochastic independence, and functional incompatibility. Current evidence fails to jointly satisfy these criteria in establishing independent systems, at least by our assessment. However, the proposed criteria are not all weighted equally in the literature. Certainly dissociation experiments, especially of neuropsychological patients, are weighted strongly in most formulations relative to the other three criteria. If all four criteria are considered equally important, as they should be in our opinion, evidence for the putative systems is much less clear-cut at this point, as indicated in our review.

Brain↗
PubMed1989

The properties of retrieval cues constrain the picture superiority effect.

In three experiments, we examined why pictures are remembered better than words on explicit memory tests like recall and recognition, whereas words produce more priming than pictures on some implicit tests, such as word-fragment and word-stem completion (e.g., completing -l-ph-nt or ele----- as elephant). One possibility is that pictures are always more accessible than words if subjects are given explicit retrieval instructions. An alternative possibility is that the properties of the retrieval cues themselves constrain the retrieval processes engaged; word fragments might induce data-driven (perceptually based) retrieval, which favors words regardless of the retrieval instructions. Experiment 1 demonstrated that words were remembered better than pictures on both the word-fragment and word-stem completion tasks under both implicit and explicit retrieval conditions. In Experiment 2, pictures were recalled better than words with semantically related extralist cues. In Experiment 3, when semantic cues were combined with word fragments, pictures and words were recalled equally well under explicit retrieval conditions, but words were superior to pictures under implicit instructions. Thus, the inherently data-limited properties of fragmented words limit their use in accessing conceptual codes. Overall, the results indicate that retrieval operations are largely determined by properties of the retrieval cues under both implicit and explicit retrieval conditions.

Adult↗
PubMed1987

Hypermnesia occurs in recall but not in recognition.

Two experiments investigated the effect of encoding conditions and type of test (recall vs. recognition) on the phenomenon of hypermnesia (improved performance across repeated tests). Subjects in Experiment 1 studied a list of words using either imaginal or semantic elaboration strategies and then received three successive tests. Different groups of subjects received either free recall, four-alternative forced-choice recognition, or yes/no recognition tests. Reliable hypermnesia was found only in the recall conditions, with the recognition conditions showing either no change in performance levels across tests (forced-choice tests) or significant forgetting (yes/no tests). In Experiment 2, subjects studied a list of words, and encoding was manipulated using three orienting tasks. Once again, hypermnesia was found with the recall tests but not with the forced choice recognition tests. Finding hypermnesia in recall but not in recognition indicates that retrieval processes in recall play a major role in producing hypermnesia. Also, the finding that the magnitude of the recall hypermnesias increased with an increase in total cumulative recall levels across study conditions suggests that cumulative recall levels are an important factor in determining the presence or absence of recall hypermnesia.

Form Perception↗