Biomedical subjects

K Murnane

Publications and source records attributed to K Murnane.

7 recordsLinked to original sources

PubMed1998

Measuring memory for source: some theoretical assumptions and technical limitations.

Henkel and Franklin (1998) present a series of well-designed experiments in support of the conclusion that memory for the source of an item is affected by the similarity between the item and other information in memory. Their principle analyses use an empirical measure of source memory that is a variant of a measure evaluated by Murnane and Bayen (1996). We point out an important assumption that underlies the use of this measure and question additional arguments and analyses that Henkel and Franklin offer in support of their conclusions. The problems discussed illustrate the need for careful consideration of the technical characteristics of measures and the theoretical assumptions on which measures rest when one is conducting research on source memory.

Cognitive Science↗

PubMed1996

Aging and the use of perceptual and temporal information in source memory tasks.

A number of studies have reported age differences in memory for the source of information. S.A. Ferguson, S. Hashtroudi, and M.K. Johnson (1992) suggested that older adults do not efficiently use multiple distinctive characteristics of sources to distinguish between sources in source memory tasks. In the study reported here, participants heard information from 2 sources and later decided whether test items had been presented by Source A, by Source B, or were new. The distinctiveness of both perceptual and temporal characteristics of sources were independently manipulated. Older adults benefited more than young adults from multiple distinctive characteristics of sources. These results question the generality of S.A. Ferguson et al.'s hypothesis.

Adolescent↗

PubMed1996

An evaluation of empirical measures of source identification.

Source identification refers to memory for the origin of information. A consistent nomenclature is introduced for empirical measures of source identification which are then mathematically analyzed and evaluated. The ability of the measures to assess source identification independently of identification of an item as old or new depends on assumptions made about how inconsistencies between the item and source components of a source-monitoring task may be resolved. In most circumstances, the empirical measure that is used most often when source identification is measured by collapsing across pairs of sources (sometimes called "the identification-of-origin score") confounds item identification with source identification. Alternative empirical measures are identified that do not confound item and source identification in specified circumstances. None of the empirical measures examined provides a valid measure of source identification in all circumstances.

Association Learning↗

PubMed1994

When does a different environmental context make a difference in recognition? A global activation model.

The effects on recognition of changes in environmental context between learning and test are examined. A context effect occurs when memory tests that take place in an environmental context that is different from the learning context produce consistent differences in performance. A formal model of context-dependent recognition within a global activation framework is presented. The model generates the predictions that (1) context effects will be present when items are tested in a new context that was not seen during learning and (2) context effects will be absent or very small when items are tested in a context that was experienced during learning but that differs from the context in which the test item was learned. Both predictions were verified in an experiment that varied the nature of the different-context test within subjects. Implications for research concerned with context-dependent recognition are discussed.

Adult↗

PubMed1993

TODAM and the list-strength and list-length effects: comment on Murdock and Kahana (1993a).

B. B. Murdock and M. J. Kahana (1993a) presented a continuous memory version of the theory of distributed associative memory (TODAM) model; they claimed that this model predicts list-strength and list-length findings, including those reported by R. Ratcliff, S. E. Clark, and R. M. Shiffrin (1990) and K. Murnane and R. M. Shiffrin (1991a). This model is quite similar to one discussed by R. M. Shiffrin, R. Ratcliff, and S. Clark (1990), who rejected the model on the basis of its inability to predict both an absent or negative list-strength effect (when strength is varied by repetitions) and a present list-length effect. In this comment we elaborate the earlier discussion and demonstrate that the version of TODAM proposed by B. B. Murdock and M. J. Kahana (1993a) indeed fails for this reason. We show this first for a somewhat simplified version of the model for which derivations are obvious and then in a simulation of the complete version using the parameter values suggested by B. B. Murdock and M. J. Kahana (1993a).

Female↗

PubMed1991

Interference and the representation of events in memory.

Most current models of memory predict that the presence of increasingly well-learned, or strong, items in memory will cause increasing interference. This phenomenon, the list-strength effect, occurs as predicted when memory is tested by free recall but not when a recognition test is used. Four experiments use end-of-session testing to demonstrate that redistribution of storage time or effort from strong to weak items on mixed lists does not occur and therefore cannot be masking interference by strong items. Delay between study and test is found to cause memory loss independent of the basic list-strength findings. It is concluded that the presence of strong items in memory does not interfere with recognition performance and that interference is due to failures of retrieval rather than to composition or other forms of destructive interaction during storage.

Analysis of Variance↗

PubMed1991

Word repetitions in sentence recognition.

When some items on a list are strengthened by extra study time or repetitions, recognition of other, unrelated, list items is not harmed (Ratcliff, Clark, & Shiffrin, 1990). Shiffrin, Ratcliff, and Clark (1990) accounted for this list-strength finding with a model assuming that different items are stored separately in memory, but that repetitions are accumulated together into a single stronger memory trace. Repeating words in the context of different sentences might cause separate storage of the repetitions of a given word, because either word or sentence traces are stored separately. Separate storage would, in effect, convert a list-strength manipulation into a list-length manipulation and thereby induce a positive list-strength effect. In Experiment 1, this result was produced for single-word recognition and for two types of sentence recognition. In Experiment 2, both words and sentences were repeated together, which should have caused repetitions to be stored in a single, stronger, trace. As expected, the list-strength effect was eliminated. A sentence trace model was fit to the data, supporting the account of Shiffrin et al. (1990) and supporting an account of word and sentence recognition in which activation is summed for representations of all list items. The results from the two studies are inconsistent with most current models of memory (as shown by the theoretical analyses of Shiffrin et al., 1990) and pose an additional challenge for theory.

Cognition↗