Gains and losses in action memory

When motion improves working memory

In the present study, we used a complex span task to explore how memory traces resulting from Self-Performed Task (SPT) and Verbal Task (VT) are maintained in working memory. Participants memorised series of five sentences describing an action either through SPT or VT. Between pairs of sentences, participants performed a concurrent task that varied according to its nature and its cognitive load. The concurrent task was either a verbal task, a low cognitive load motor task or a high cognitive load motor task. A control condition served as a baseline. First, we observed that performance in SPT and VT did not decrease with verbal or motor suppression, but was lower with an increase of the cognitive load. This suggests that memory traces are maintained through attentional refreshing whatever the encoding (SPT or VT). Second, while the enactment effect was replicated in the control condition, it tended to vanish with a verbal concurrent task; moreover, it was reversed with motor concurrent tasks. Surprisingly, the latter effect resulted from an increase of VT memory performance when participants repeated the same gesture between sentences. Finally, our results provide additional evidence that the enactment effect does not rely on attention.

Evaluating the subject-performed task effect in healthy older adults: relationship with neuropsychological tests

Background

An enhancement in recall of simple instructions is found when actions are performed in comparison to when they are verbally presented – the subject-performed task (SPT) effect. This enhancement has also been found with older adults. However, the reason why older adults, known to present a deficit in episodic memory, have a better performance for this type of information remains unclear. In this article, we explored this effect by comparing the performance on the SPT task with the performance on other tasks, in order to understand the underlying mechanisms that may explain this effect.

Objective

We hypothesized that both young and older adult groups should show higher recall in SPT compared with the verbal learning condition, and that the differences between age groups should be lower in the SPT condition. We aimed to explore the correlations between these tasks and known neuropsychological tests, and we also measured source memory for the encoding condition.

Design

A mixed design was used with 30 healthy older adults, comparing their performance with 30 healthy younger adults. Each participant was asked to perform 16 simple instructions (SPT condition) and to only read the other 16 instructions (Verbal condition – VT). The test phase included a free recall task. Participants were also tested with a set of neuropsychological measures (speed of processing, working memory and verbal episodic memory).

Results

The SPT effect was found for both age groups; but even for SPT materials, group differences in recall persisted. Source memory was found to be preserved for the two groups. Simple correlations suggested differences in correlates of SPT performance between the two groups. However, when controlling for age, the SPT and VT tasks correlate with each other, and a measure of episodic memory correlated moderately with both SPT and VT performance.

Conclusions

A strong effect of SPT was observed for all but one, which still displayed the expected aging deficit. The correlations and source memory data suggest that the SPT and VT are possibly related in respect to their underlying processes, and SPT, instead of being an isolated process, is in connection with both the episodic memory and executive function processes. Under these circumstances, the SPT seems to contribute to an enhancement of the episodic memory trace, presumably from the multimodality it provides, without involving a separated set of cognitive mechanisms. Future research using more pure measures of other cognitive processes that could be related to SPT is necessary.

Enactment versus observation: item-specific and relational processing in goal-directed action sequences (and lists of single actions)

What are the memory-related consequences of learning actions (such as "apply the patch") by enactment during study, as compared to action observation? Theories converge in postulating that enactment encoding increases item-specific processing, but not the processing of relational information. Typically, in the laboratory enactment encoding is studied for lists of unrelated single actions in which one action execution has no overarching purpose or relation with other actions. In contrast, real-life actions are usually carried out with the intention to achieve such a purpose. When actions are embedded in action sequences, relational information provides efficient retrieval cues. We contrasted memory for single actions with memory for action sequences in three experiments. We found more reliance on relational processing for action-sequences than single actions. To what degree can this relational information be used after enactment versus after the observation of an actor? We found indicators of superior relational processing after observation than enactment in ordered pair recall (Experiment 1A) and in emerging subjective organization of repeated recall protocols (recall runs 2-3, Experiment 2). An indicator of superior item-specific processing after enactment compared to observation was recognition (Experiment 1B, Experiment 2). Similar net recall suggests that observation can be as good a learning strategy as enactment. We discuss possible reasons why these findings only partly converge with previous research and theorizing.

Retrieval-Induced Forgetting of Performed and Observed Bizarre and Familiar Actions

To investigate whether people show retrieval-induced forgetting (RIF) for bizarre and familiar actions that they performed or observed, three experiments were conducted. In Experiment 1, participants performed bizarre and familiar actions with different objects during learning (e.g., pencil: balance the pencil across the cup, sharpen the pencil). They repeatedly performed a set of the bizarre or familiar actions during retrieval practice. After a distracter task, participants’ cued recall was tested. Participants showed RIF for both bizarre and familiar actions. In Experiment 2, half of the participants performed the bizarre and familiar actions themselves; the other half observed the experimenter performing the actions. Replicating the results of Experiment 1, participants who performed the actions showed RIF for bizarre and familiar actions. In contrast, participants who observed the actions did not show RIF for either action type. Experiment 3 examined whether this lack of RIF for observed actions occurred due to a lack of active recall during retrieval practice; it did. Overall, the three experiments demonstrated RIF for both bizarre and familiar performed and observed actions. A distinctiveness account of the results is provided.

Hypermnesia and total retrieval time

Recall performance sometimes improves over repeated recall attempts, a phenomenon dubbed hypermnesia. A critical theoretical issue is whether hypermnesia is due to repeated testing per se or increased retrieval time. The present experiments investigated by contrasting five testing conditions. All participants were presented with the same study list followed by either two shorter recall tests or a single longer test. In the multiple test conditions, the tests were either separated by a (filled) 7-minute interval (the multiple-split condition), or presented consecutively, with no break (the multiple-immediate condition). In the single test conditions, the test either began at the start of the recall session, after a (filled) 7-minute delay, or with a 7-minute interruption inserted in the middle. The multiple-split condition produced more reminiscence and hypermnesia than the multiple-immediate condition. More importantly, the multiple-split condition produced greater cumulative recall than any of the other conditions (which did not differ among themselves). That is, single and repeated recall tests of equal total duration are not functionally equivalent.

Decomposing retrieval and integration in memory for actions: a multinomial modeling approach

Typically, action phrases are recalled better if participants are asked to enact the phrases than if they are just asked to remember them. When investigating which processes constitute this enactment effect a difficulty is that observable effects in standard memory tests are ambiguous because such tests require several processes. In the present article, we introduce a multinomial model that decomposes observable memory performance into a retrieval parameter and a parameter concerning the item-specific processing and integration of an action phrase. These parameters are estimated from free recall and cued recall performance. The model fitted the data of two experiments designed to test it. Experiment 1 demonstrated the basic usefulness of the model by showing expected differences in the integration parameter in the absence of unexpected differences in the retrieval parameter. Experiment 2 extended the conditions under which the model is useful by showing expected differences in the retrieval parameter even in the presence of unexpected differences in the integration parameter. Together, these findings support our theoretical framework according to which enactment generally boosts integration of action phrases, but increases retrieval only for phrases with context cues.

An item gains and losses analysis of false memories suggests critical items receive more item-specific processing than list items

In a repeated testing paradigm, list items receiving item-specific processing are more likely to be recovered across successive tests (item gains), whereas items receiving relational processing are likely to be forgotten progressively less on successive tests. Moreover, analysis of cumulative-recall curves has shown that item-specific processing produces a slower, but steadier rate of recall than relational processing. The authors relied on these findings to determine the type of processing that both list items and critical lures receive in the Deese-Roediger-McDermott false memory procedure. The first 2 experiments revealed that critical lures produced more item gains, but only the list items resulted in a decrease in item losses across successive tests. The critical lures also produced slower but steadier cumulative recall. In Experiments 3 and 4, the critical items were physically presented during study, which resulted in the lures producing progressively fewer losses across successive tests. The authors concluded that critical items receive more item-specific processing than list items but that unless they are presented in the list, they do not become part of participants' organized retrieval scheme.

Differential relational encoding of categorical information in memory for action events

Memory for action phrases is better if the actions are enacted in subject-performed tasks (SPTs) than if they are only listened to in verbal tasks (VTs). This effect is ascribed to better item-specific encoding of SPTs than of VTs. The role of interitem relational information is controversial, and the findings of clustering with categorically structured lists are inconsistent (see Engelkamp, 1998). The present study contributes to clarifying these effects by demonstrating that intentional relational encoding can be used more efficiently in VTs than in SPTs and influences the degree of clustering. If the list structure is not obvious, inducing intentional encoding by presenting the category labels prior to list presentation and asking subjects to use this preinformation increases clustering in VTs but not in SPTs. Without preinformation, clustering scores of VTs and SPTs did not differ, with preinformation, clustering of VTs was stronger than that of SPTs. The authors suggest how the inconsistent findings with regard to clustering effects can be explained.

Lexical, conceptual and motor information in memory for action phrases: a multi-system account

According to the multi-system account [J. Engelkamp, H.D. Zimmer, The Human Memory: A Multi-Modal Approach, Hogrefe & Huber, Seattle, 1994], the enactment effect in free recall of action phrases (e.g. break the stick) is independent of inter- and intra-phrase associations because it emerges from the nonverbal encoding processes under enactment. Two experiments have been reported which tested these and further assumptions of the multi-system account of the enactment effect. In both experiments, inter- and intra-phrase (verb-object) associations were varied simultaneously in addition to enactment. In Experiment 1, the memory test was free recall, and in Experiment 2, it was cued recall. Independent effects of all three factors were observed in free recall. Enacted phrases were recalled better than phrases learned only verbally. Phrases with high-associated objects and verbs were better recalled than phrases with low-associated objects and verbs, and categorically related phrases were better recalled than unrelated phrases. In cued recall, there was no effect of categorical list structure. The effects of intra-phrase structure and enactment corresponded to those in free recall. All interactions were nonsignificant. The findings were interpreted as support for the multi-system account.