The Atkinson-Shiffrin model is ill-defined and does not correctly describe the Murdock free recall data

Tarnow, Dr. Eugen (2009) The Atkinson-Shiffrin model is ill-defined and does not correctly describe the Murdock free recall data. [Preprint]

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The Atkinson-Shiffrin (1968) model, the de facto standard model of short term memory cited thousands of times, fits the characteristically bowed free recall curves from Murdock (1962) well. However, it is long overdue to note that it is not a theoretically convincing explanation and that it does not fit all of the experimental relationships in the Murdock data. To obtain a qualitatively correct fit of the bowing I show that four model concepts have to work together. “Long term memory” is needed in the short term memory experiment, conscious or subconscious rehearsal of four items has to take place, this “rehearsal buffer” has to drop items randomly rather than according to a first-in firstout model, and the rehearsal buffer has to be empty before the experiment starts. Beyond the qualitative fit to the bowed recall curves, other relationships in the data are not borne out by the model. First, the “primacy strength”, the ratio of the probability of recall of the first item to the smallest probability of recall of an intermediate item, shows a significant experimental variation with presentation rate but no such variation is predicted by theory. Second, randomly emptying the rehearsal buffer predicts incorrectly that the number of recalled items should be the highest when the first recalled item is the last list item. Third, a simplified Atkinson-Shiffrin model is found to predict exact relationships between the recall probabilities of the initial items which do not seem to be borne out by the Murdock data. Fourth, the theory predicts a discontinuity in the differences between free recall graphs with different presentation rates for early list items which is probably not found in the Murdock data.

Item Type:Preprint
Keywords:Short term memory, atkinson, shiffrin
Subjects:Psychology > Cognitive Psychology
ID Code:6744
Deposited By: Tarnow, Dr. Eugen
Deposited On:19 Dec 2009 11:49
Last Modified:11 Mar 2011 08:57

References in Article

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Atkinson, R.C. and Shiffrin, R.M. (1968) Human memory: a proposed system and its control processes. In:

Spence K.W. and Spence J.T. (Eds.), The Psychology of Learning and Motivation: Advances in Research and

Theory, Vol. 2. Academic Press, New York, pp. 89–195.

Cowan N. (2000). The magical number 4 in short-term memory: A reconsideration of mental storage capacity.-

Behavioral and Brain Sciences 24(1):87-114.

Cowan N, Rouder JN, Stadler MA, (2000) “Conjuring a Work From the Dream Time of Cognitive Psychology”

The American Journal of Psychology, Vol. 113, No. 4 (Winter, 2000), pp. 639-648

Cowan N. Saults JS, Elliott EM, Moreno MV (2002). Deconfounding serial recall. Journal of Memory and

Language 46, 153-177.

Craik, F. I. M. (1969). Modality effects in short-term storage. Journal of Verbal Learning and Verbal Behavior, 8,


Kandel, E.R. (2001). The Molecular Biology of Memory Storage: A Dialogue Between Genes and Synapses.

Science, pp. 1030-1038.

Murdock Jr., Bennet B. The serial position effect of free recall. Journal of Experimental Psychology. Vol 64(5),

Nov 1962, 482-488.

Raaijmakers, J.G.W. & Shiffrin, R.M. (1981). Order effects in recall. In J.B. Long and A.D. Baddeley (Eds),

Attention and Performance IX (Pp. 403-415). Hillsdale, N.J.: Erlbaum.

Rubin DC, Hinton S, Wenzel A.(1999). The Precise Time Course of Retention. Journal of Experimental

Psychology: Learning, Memory and Cognition, Vols. 25:1161-1176.

Shiffrin, R,M. (1968). Search and retrieval process in long-term memory. Technical Report No. 137, Institute for

Mathematical Studies in the Social Sciences, Stanford University.

Shiffrin, R.M. (1970). Memory search. In D.A. Norman (Ed.), Models of human memory. (Pp. 375-447). New

York: Academic Press.

E. Tarnow. (2008). Response probability and response time: a straight line, the Tagging/Retagging interpretation

of short term memory, an operational definition of meaningfulness and short term memory time decay and

search time. Cognitive Neurodynamics, 2 (4) p. 347-353.


E Tarnow. (2009) Short term memory may be the depletion of the readily releasable pool of presynaptic

neurotransmitter vesicles of a metastable long term memory trace pattern. Cognitive Neurodynamics 3:3 263-


E Tarnow. (2009b) Short term memory decays and high presentation rates hurry this decay: The Murdock free

recall experiments interpreted in the Tagging/Retagging model. Accepted to Cognitive Neurodynamics.


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