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M S Weldon

Publications and source records attributed to M S Weldon.

10 recordsLinked to original sources
PubMed2000

Group remembering: does social loafing underlie collaborative inhibition?

When people collaborate to recall information, they experience collaborative inhibition, a deficit in recall relative to nominal groups (the pooled, nonredundant recall of individuals working alone). That is, people recalling in groups do not perform up to their potential. Collaborative inhibition may be due to retrieval interference (e.g., B. H. Basden, D. R. Basden, S. Bryner, & R. L. Thomas, 1997) or to motivational factors such as social loafing in the group situation. Five experiments examined the role of motivational factors by varying monetary incentives, recall criterion, personal accountability, group cohesion, and group gender. Increasing motivation sometimes increased the overall level of recall but failed to eliminate the collaborative inhibition effect. The results suggest that collaboration interferes with an individual's ability to reconstruct his or her knowledge.

Adolescent↗
PubMed1996

Integration of orthographic, conceptual, and episodic information on implicit and explicit tests.

An experiment was conducted to determine how orthographic and conceptual information are integrated during incidental and intentional retrieval. Subjects studied word lists with either a shallow (counting vowels) or deep (rating pleasantness) processing task, then received either an implicit or explicit word fragment completion (WFC) test. At test, word fragments contained 0, 1, 2, or 4 letters, and were accompanied by 0, 1, 2, or 3 semantically related words. On both the implicit and explicit tests, performance improved with increases in the numbers of letters and words. When semantic cues were presented with the word fragments, the implicit test became more conceptually drive. Still, conceptual processing had a larger effect in intentional than in incidental retrieval. The Fuzzy Logical Model of Perception (FLMP) provided a good description of how orthographic, semantic, and episodic information were combined during retrieval.

Adult↗
PubMed1996

Remembering the earthquake: direct experience vs. hearing the news.

Three groups of informants--two in California, one in Atlanta--recalled their experiences of the 1989 Loma Prieta earthquake shortly after the event and again 11/2 years later. The Californians' recalls of their own earthquake experiences were virtually perfect. Even their recalls of hearing the news of an earthquake-related event were very good: much higher than Atlantan recalls of hearing about the quake itself. Atlantans who had relatives in the affected area remembered significantly more than those who did not. These data show that personal involvement in the quake led to greatly improved recall, but do not show why. Many Californian informants reported low levels of stress/arousal during the event; arousal ratings were not significantly correlated with recall. The authors suggest that repeated narrative rehearsals may have played an important role.

Affect↗
PubMed1993

The time course of perceptual and conceptual contributions to word fragment completion priming.

Two experiments examined the time course of the availability of perceptual and conceptual information in priming on the word fragment completion test. Subjects encoded primes as either visual words, auditory words, or pictures. In Experiment 1, word fragments were exposed for either 500 ms, 1 s, 5 s, or 12 s. Only the visual words produced priming at the 500-ms and 1-s exposure times. In Experiment 2, subjects were allowed up to 20 s to solve each fragment; response latencies were recorded and cumulative response curves were generated. Visually primed fragments were solved at a faster rate than either auditorily or pictorially primed fragments. The results suggest that although conceptual processing can contribute to word fragment priming, perceptual processes are recruited earlier and at a faster rate.

Attention↗
PubMed1993

Why do pictures produce priming on the word-fragment completion test? A study of encoding and retrieval factors.

Three experiments examined why pictures produce priming on the word-fragment completion test, despite the fact that there is no match between the physical features of the picture and the word fragment. Pictures and words were presented as primers, and performance on the word-fragment completion test was measured; encoding and retrieval conditions were varied. Experiments 1 and 2 examined the role of picture labeling by increasing the presentation rate and by introducing a shadowing task during encoding; labeling appears to play a role in priming. In Experiment 3, the word fragments were presented for 500 msec, and subjects were required to provide a solution immediately. Word priming was unaffected, but picture priming was eliminated, suggesting that word fragments enable efficient recovery of perceptually similar primes (i.e., words), but slower and less direct recovery of conceptually similar but physically dissimilar primes (i.e., pictures).

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↗
PubMed1991

Integration of orthographic and semantic information in memory retrieval.

Our central goal was to determine how multiple sources of information are evaluated and integrated during memory retrieval. An expanded factorial design was used to vary two sources of information independently of one another and to present each source alone. Subjects solved crossword-like puzzles with varying numbers of orthographic and semantic cues. The results of the experiment indicated that (a) performance is better given two sources of information relative to just one; (b) evaluation of each source of information provides continuous rather than just categorical (all-or-none) information; and (c) the two sources are integrated multiplicatively rather than simply used independently of one another as claimed by nonintegration models. A fuzzy logical model of perception (FLMP)-taken from the pattern recognition domain--gave a good description of the memory results. A single channel model, an averaging model, and an adding model produced poor descriptions of the results.

Adult↗
PubMed1991

Mechanisms underlying priming on perceptual tests.

Four experiments examined perceptual, lexical, and conceptual processing effects in priming on word fragment completion (WFC) and perceptual identification (PID). In Experiment 1, visual words produced more priming than auditory or generated words, and pictures produced the least priming, suggesting that the effects of different encoding processes can be distinguished. In Experiments 2 and 3, Ss studied anagrams (e.g., tripocs), but only Ss instructed to think of the original words by mentally interchanging the vowels exhibited significant priming. Thus, lexical access is more important than surface similarity in priming. In Experiment 4, Ss studied compounds that either preserved the target's meaning (e.g., scotch bottle) or altered its meaning (e.g., scotch tape). Encoded meaning affected priming on WFC but not on PID, suggesting that conceptual processing plays a larger role in WFC. Overall the results suggest that priming must be understood in terms of multiple processes.

Attention↗
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↗