From Short-term Memory to Working Memory

The concept of primary memory (PM) in the levels-of-processing (LOP) framework is described and illustrated. The history of the short-term/long-term memory (STM/LTM) distinction is reviewed. Early studies of STM in the Craik laboratory are described, including work on dichotic listening, the negative recency effect, and the surprising finding of long-lasting auditory information in STM. The distinction between PM and secondary memory is reviewed, and their respective roles in short-term retention discussed. Some experiments on release from proactive interference are described. The theoretical evolution of the construct of PM to that of working memory (WM) is described. The proposal that WM is equivalent to “attention paid to information in conscious awareness” is evaluated. It is argued that PM and WM are not separate entities, but are on a descriptive continuum. Further topics include the role of secondary memory in WM, and the possibility of LOP effects in WM (explored in experiments carried out by Craik and Nathan Rose). Further topics include a consideration of WM as a set of separable abilities, hierarchical views of WM, and a final integrated view of short-term retention.

The effect of sign language rehearsal on deaf subjects' immediate and delayed recall of English word lists

ABSTRACTThe relationship between sign language rehearsal and written free recall was examined by having deaf college students overtly rehearse the sign language equivalents of printed English words. In studies of both immediate and delayed memory, word recall was found to increase as a function of total rehearsal frequency and frequency of appearance in rehearsal sets. The serial recall curves in both memory experiments evidenced a primacy effect, which was interpreted as resulting from increased rehearsal of the words in the initial positions over the course of the list. In contrast to findings from previous short- and long-term memory studies with normally hearing subjects, neither a recency nor a negative recency effect was found. High imagery words were rehearsed and recalled slightly more frequently in immediate memory, but there was no effect resulting from the different imagery values of the stimuli in delayed recall. These results are discussed in relation to current conceptualizations of memory and of linguistic processing by deaf individuals.

Memory for Pictures and Words, and the Negative Recency Effect

This experiment investigated performance in a final, cumulative test of a subject's ability to recall a series of lists. No negative recency effect was found with either pictures of objects or their names. This supports the suggestion of earlier research that the negative recency effect stems from failure to employ mental imagery as a mnemonic code on terminal serial positions and that visual presentation promotes the use of imagery throughout a list.

Mental Imagery and the Distinction between Primary and Secondary Memory

Previous research has shown that the imageability of stimulus material affects the secondary memory (SM) component of free recall, but not the primary memory (PM) component, and that a negative recency effect is only observed for material of high imageability. It was found that interactive imagery instructions affected the SM component, but not the PM component; separative imagery instructions led to an increased PM component and a reduced SM component. A negative recency effect can be observed in an initial, delayed recall test. However, it is removed by imagery mnemonic instructions. This supports the idea that the negative recency effect is caused by the fact that subjects do not normally image the last few words presented in a free-recall task.

Sequential Effects in a Two-Choice Serial Reaction Task

Twenty-four subjects performed a symbolic two-choice serial reaction task under four conditions. These were with a delay from previous response to onset of next stimulus of 100 millisec, 600 millisec., 2 sec., and a fourth condition of 2 sec. delay with verbal prediction of the next stimulus. A positive recency or repetition effect occurred at 100 millisec. delay where RTs to repeated stimuli were faster than RTs to alternate stimuli. At 600 millisec. this effect was still present, though much reduced. The 2 sec. delay gave a negative recency effect where RTs were slower to repeated than to alternate stimuli. This effect increased significantly with simultaneous prediction of the next stimulus. The verbal predictions themselves displayed negative recency. Run analysis of the four conditions revealed striking differences. These results emphasize the need for analysing the microstructure of choice RT situations and reveal deficiencies in present models.