Testing the Idea of Distinct Storage Mechanisms in Memory

Abstract

This paper sets out quantitative foundati ons for testing the idea that memory is served by two distinct storage mechanis ms, a short-term and a separate long-te rm store, using data fro m the single-trial free-recall experiment by M urdock and Oka da (1970). In single-trial free recall one can observe which word is recalled next and how long that recall takes, but that is all. So justi® cation for two separate stores must turn either on the probabilities of recall, or on the latencie s, for pa rticular serial position s in the stimulus list.(a) Nearly one-thir d of all recalls after the ® rst are successors (Word n+1 im mediately follow ing recall of Word n). So recall is do minated, not by absolute serial position (as a short-term store would require), but by position relative to the preceding recall.(b) To a ® rst approximation, all ® rst recalls have the same latency distribu tion except for Word 1. A co mmon latency distribution is co mpatible with a single store. A n exp lanation is offered why Word 1 should take longer, in which Word 1 is the second retrieval fro m a co m mon store.The idea of two separate stores appears to lack experimental support.Cet article propose un test quantita tif de l' ide e selon la quelle la me moire co mprendrait deux me canis mes distincts d' em magasinage, un me canis me a Á court ter me et un me canis me a Á long terme. Les donne es d' une expe rience de M urdock et Okada (1970), dans laquelle un seul essai de rappel libre e tait pre sente , sont utilise es. D ans cette taà che, il est possible de ve ri® er quel mot est rappele apre Á s un autre mot et co mbien de te mps prend ce rappel, mais ce sont la Á les deux seules mesures disponibles. D ans ces conditio ns, la justi® cation de l' existence de deux syste Á mes se pa re s doit eà tre base e soit sur les probabilite s de rappel ou sur le te mps de latence pour des position s se rielles spe ci® ques.(a) Pre Á s d' un tiers de tous les mots rappele s apre Á s le premier sont des successeurs (M ot n+1 suit im me diate ment le rappel du M ot n). Le rappel est donc do mine par la positio n relative de l' ite m rappele pre ce dem ment et non pas par la pos ition se rielle absolue (co mme l' exigerait l' hypothe Á se d' un syste Á me a Á court terme).(b) Tous les premiers rappels ont approximative ment la meà me distribu tion de latence, excepte le M ot 1. Cette distribu tion de latence est co mpatible avec un syste Á me unitaire de me moire. Le te mps de latence plus long pour le M ot 1 serait attribuable au fait que celui-c i est le second a Á eà tre re cupe re d' un syste Á me co m mun.L' ide e de deux syste Á mes se pare s de me moire semble manquer de appui empirique.IN TERNAT IO NAL JOU RNA L OF PSYCH OLOGY, 1999 , 34 (5/6), 419± 426Request s for reprints should be addresse d to D onald La ming,

The Temporal Context Model in Spatial Navigation and Relational Learning: Toward a Common Explanation of Medial Temporal Lobe Function Across Domains.

“…The last column in Table 2 gives the probability that the first item re-called with t T as a cue will be A, B or C. These values add up to one, which is consistent with the definition of the probability of first recall (Laming, 1999;Howard & Kahana, 1999). It is important to note that while TCM has been applied extensively to free recall, it does not contain any of the sampling and recovery rules that would be necessary to produce a complete description of the task (such as those specified by SAM Raaijmakers & Shiffrin, 1980,1981.…”

The role of rehearsal on the output order of immediate free recall of short and long lists.

“…Not only are the recency items the most likely to be recalled, but they are also those most likely to be recalled first from a long list of words (e.g., Beaman & Morton, 2000;Farrell, 2010;Hogan, 1975;Howard & Kahana, 1999;Laming, 1999), and subsequent recalls are most likely to be from neighboring input serial positions (e.g., Howard & Kahana, 1999; 5 Kahana, 1996) and / or neighboring rehearsals (e.g., Laming, 2010;Ward, Woodward, Stevens, & Stinson, 2003).…”

“…A related idea is that participants might try to retrieve the "Get Ready" warning signal that is typically used prior to the presentation of the first list item (Laming, 1999(Laming, , 2010, in order to gain privileged initial access to serial position 1. Finally, the participants' internal contextual state could be the functional first item on the list (Metcalfe & Murdock, 1981) to which subsequent items are 36 associated.…”

“…They confirmed that for longer lists of 10 or more words, participants tended to initiate their recall with one of the last four list items (cf. Hogan, 1975;Howard & Kahana, 1999;Laming, 1999), and on these trials, the serial position curves were dominated by extended recency effects and smaller primacy effects. Critically, they also found that for the IFR of shorter lists of words, participants tended to initiate output with the very first list item and, when this occurred, the resultant serial position curves showed elevated levels of recall of the early list items and greatly reduced recency.…”

“…Although there are some models that attempt to explain both tasks (e.g., Anderson, Bothell, Lebiere & Matessa, 1998; Farrell, in press;Grossberg & Pearson, 2008), the majority of accounts of IFR say little about ISR (e.g., Davelaar, et al, 2005;Howard & Kahana, 2002;Laming, 2006Laming, , 2008Laming, , 2009Laming, , 2010Polyn et al, 2009;Raaijmakers & Shiffrin, 1981;Sederberg et al, 2008;Tan & Ward, 2000;Unsworth & Engle, 2007), and the majority of the accounts of ISR say little about IFR (e.g., Baddeley, 1986Baddeley, , 2000Baddeley, , 2007Baddeley & Hitch, 1974;Botvinick & Plaut, 2006;Brown, Preece, & Hulme, 2000;Burgess & Hitch, 1992, 1999, 2006Farrell & Lewandowsky, 2002;Lewandowsky & Farrell, 2008;Nairne, 1990;Oberauer & Lewandowsky, 2008;Page & Norris, 1998). Moreover, a common theoretical framework for the two tasks remains controversial (for different views on this issue, see e.g., Brown, Chater, & Neath 2008;Murdock, 2008).…”