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Biomedical subjects

J M Gardiner

Publications and source records attributed to J M Gardiner.

At least 19 recordsLinked to original sources

Involuntary conscious memory and the method of opposition.

Priming in an indirect test of stem completion should reflect involuntary memory, but can be accompanied by conscious awareness of the past (involuntary conscious memory) or unaccompanied by such awareness (involuntary unconscious memory). We adapted the method of opposition developed by Jacoby, Woloshyn, and Kelley (1989) to obtain a measure of stem-completion priming that should reflect only involuntary unconscious memory. Subjects completed stems with the first word coming to mind, but wrote down a different word if the word that came to mind first had been previously encountered. Facilitatory priming was expected only when involuntary unconscious influences outweighed inhibitory effects of involuntary conscious memory, or of intentional retrieval. We observed a facilitation effect for items processed graphemically at encoding, in conjunction with an inhibition effect for items processed semantically at encoding. In contrast, a standard indirect test showed similar levels of priming following graphemic and semantic encoding, whereas a direct test showed a strong advantage of semantic over graphemic encoding. We argue that the two encoding activities produced approximately equivalent involuntary influences of memory, but that items encoded semantically were associated with involuntary conscious memory to a greater extent than were items encoded graphemically. Comparing indirect and opposition test performance can provide a quantitative index of relative levels of involuntary conscious and involuntary unconscious memory.

Analysis of Variance

Mathematical constraints and the Tulving-Wiseman law: a rejoinder.

Hintzman (1991; 1992) has claimed that the reason data points approximate the recognition failure function discovered by Tulving and Wiseman (1975) is that they are mathematically constrained to do so, and the reason that a few data points do not approximate the function, but are exceptions to it, is that these data points are less subject to mathematical constraints. He has additionally argued that such exceptions are more likely with low levels of recall and strong underlying sources of positive covariance. We provide empirical evidence relevant to this mathematical model using 301 observations from a database of all relevant experimental conditions published between 1973 and 1992 (Nilsson & Gardiner, 1993). We conclude that mathematical constraints have only a minor influence on the function, not the causal role assigned to them in Hintzman's (1992) model. By our account, both the function and exceptions to it reflect a single psychological principle, the functional effectiveness of contextual cues.

Cues

Forgetting in recognition memory with and without recollective experience.

Retention interval was manipulated in two recognition-memory experiments in which subjects indicated when recognizing a word whether its recognition was accompanied by some recollective experience ("remember") or whether it was recognized on the basis of familiarity without any recollective experience ("know"). Experiment 1 showed that between 10 min and 1 week, "remember" responses declined sharply from an initially higher level, whereas "know" responses remained relatively unchanged. Experiment 2 showed that between 1 week and 6 months, both kinds of responses declined at a similar, gradual rate and that despite quite low levels of performance after 6 months, both kinds of responses still gave rise to accurate discrimination between target words and lures. These findings are discussed in relationship to current ideas about multiple memory systems and processing accounts of explicit and implicit measures of retention.

Adult

Priming and aging: further evidence of preserved memory function.

Priming effects in word-stem completion were compared with cued recall in young and older adults. Cued recall showed large effects of age and also of levels of processing, but these variables had little influence on priming in word-stem completion. Free recall showed large effects of age as well as superior recall for words that had been generated rather than read at study, but priming in word-stem completion was little influenced by age, and it was greater for words that had been read at study rather than generated. These findings were interpreted as providing further evidence that age-related impairments in memory performance are greatly reduced in implicit compared with explicit tests. They also provide convergent evidence for classifying word-stem completion as a data-driven rather than conceptually driven task.

Adolescent

Attention and recollective experience in recognition memory.

The functional relation between recognition memory and conscious awareness was assessed in an experiment in which undivided attention at study was compared with two divided attention conditions, one more demanding than the other. When recognizing a word from the study list, subjects indicated whether they could consciously recollect its prior occurrence or recognized it on some other basis, in the absence of conscious recollection. Divided attention at study progressively impaired word recognition accompanied by conscious recollection. Recognition in the absence of conscious recollection was not affected by divided attention. These findings are interpreted as providing further support for the idea that recognition memory entails two distinct components, one based on associative and contextual information, the other based on a "traceless" awareness of familiarity.

Adult

The Tulving-Wiseman law and the recognition of recallable music.

Memory for well-known musical phrases was tested first for recognition in the absence of any specific musical context and then for recall given the preceding musical phrase as a contextual cue. Recognition and recall were found to be largely, but not completely, independent. Moreover, there was no evidence of any greater dependency between recognition and recall than that previously observed in the relation between word recognition and recall, as summarized by the Tulving-Wiseman law. These findings significantly extend the range of applicability of this law.

Adult

Recollective experience in word and nonword recognition.

The functional relationship between memory and consciousness was investigated in two experiments in which subjects indicated when recognizing an item whether they could consciously recollect its prior occurrence in the study list or recognized it on some other basis, in the absence of conscious recollection. Low-frequency words, relative to high-frequency words, enhanced recognition accompanied by conscious recollection but did not influence recognition in the absence of conscious recollection. By contrast, nonwords compared with words enhanced recognition in the absence of conscious recollection and reduced recognition accompanied by conscious recollection. A third experiment showed that confidence judgments in recognizing nonword targets corresponded with recognition performance, not with recollective experience. These measures of conscious awareness therefore tap qualitatively different components of memory, not some unitary dimension such as "trace strength." The findings are interpreted as providing further support for the distinction between episodic memory and other memory systems, and also as providing more qualified support for theories that assume that recognition memory entails two components, one of which may also give rise to priming effects in implicit memory.

Adult

Membrane lipids and enzymes of cultured high- and low-metastatic B16 melanoma variants.

B16 melanoma cell variants were used to determine if the metastatic properties of these cells could be correlated to distinct plasma membrane, microsome, and mitochondrial membrane lipid compositions and membrane-bound enzyme activities in high- and low-metastatic cell variants, respectively. The high-metastatic B16-F10 melanoma cell membranes had lower cholesterol/phospholipid ratios, lower arachidonic acid content, lower polyunsaturated fatty acid content, higher phosphatidylcholine/phosphatidylethanolamine ratios, and higher succinate cytochrome c reductase activity than those of B16-F1 melanoma cell membranes. No differences in cholesterol/phospholipid ratio were noted in the mitochondria. Na+-K+-adenosinetriphosphatase activity and solubility of 5'-nucleotidase activity were also similar. The data indicate that the membrane lipid composition of B16-F10 melanoma cells is distinct from that of B16-F1 melanoma cells and may help to elucidate the molecular basis for the different metastatic properties of these cell lines in vivo.

Adenosine Triphosphatases

On recency and echoic memory.

In short-term memory, the tendency for the last few (recency) items from a verbal sequence to be increasingly well recalled is more pronounced if the items are spoken rather than written. This auditory recency advantage has been quite generally attributed to echoic memory, on the grounds that in the auditory, but not the visual, mode, sensory memory persists just long enough to supplement recall of the most recent items. This view no longer seems tenable. There are now several studies showing that an auditory recency advantage occurs not only in long-term memory, but under conditions in which it cannot possibly be attributed to echoic memory. Also, similar recency phenomena have been discovered in short-term memory when the items are lip-read, or presented in sign-language, rather than heard. This article provides a partial review of these studies, taking a broad theoretical position from which these particular recency phenomena are approached as possible exceptions, to a general theory according to which recency is due to temporal distinctiveness. Much of the fresh evidence reviewed is of a somewhat preliminary nature and it is as yet unexplained by any theory of memory. The need for additional, converging experimental tests is obvious; so too is the need for further theoretical development. Several alternative theoretical resolutions are mentioned, including the possibility that enhanced recency may reflect movement, from sequentially occurring stimulus features, and the suggestion that it may be associated with the primary linguistic mode of the individuals concerned. But special weight is attached to the conjecture that all these recency phenomena might be accounted for in terms of distinctiveness or discriminability. On this view, the enhanced recency effects observed with certain modes, including the auditory mode, are attributed to items possessing greater temporal discriminability in those modes.

Auditory Perception

Further evidence of interference between lipreading and auditory recency.

In both free and backward recall, it is shown that auditory but not visual recency is greatly disrupted when subjects have to lipread, rather than read, a series of numbers in a distractor task interpolated between list presentation and recall. This selective interference effect extends the generality of a finding reported by Spoehr and Corin (1978) and adds to an accumulating body of evidence that seems inconsistent with acoustic or echoic memory interpretations of the enhanced recency recall typically observed in comparing auditory with visual presentation. Alternative interpretations are briefly considered.

Humans

Influences of delayed distraction on the modality effect in free recall.

The free recall recency items is better following lists presented auditorily rather than visually. This modality effect was eliminated by a 30-second, but not a three-second, period of auditory distraction delayed by 15 seconds following list presentation. It is argued that these findings are entirely consistent with the notion that the modality effect in free recall arises from the direct use of persistent modality-specific information, and not from the use of acoustic information which has been recoded into modality-independent memory.

Attention