Memory of self-performed tasks: Self-performing during recognition

Two experiments focused on whether performing actions described by to-be-remembered phrases during recognition enhances recognition compared with results of a standard verbal recognition test. The enhancement was predicted when the actions described by the phrases had been performed during study, but not when the phrases were verbally encoded by simply listening to and memorizing the material. Both experiments showed that enactment prior to recognition improved memory performance, but only when subjects had encoded by enactment. Experiment 1 also demonstrated that this test-procedure effect was independent of a bizarreness effect, which was observed only with the verbal encoding task. Experiment 2 showed that the effect of enactment during recognition was reduced when subjects used different hands for performing the actions during study and recognition- The findings support the assumption that some kind of motor memory record underlies the enactment effect that occurs when actions are performed during recognition.     

Signing enhances memory like performing actions

In three experiments, we investigated the influence of the overt performance of signs on memory. Deaf and hearing participants studied lists of action phrases (Experiment 1) or nouns (Experiment 2) under standard verbal instruction, under the instructions to sign the verbal phrase, to symbolically perform the denoted action, or to carry out a prototypical action corresponding to each noun. Higher recall and recognition performances were observed when actions were performed than in the verbal encoding condition, and signing was as effective for memory as was enactment. Thus, overt signing can induce an enactment effect. In contrast, Experiment 3 demonstrated that performing an unrelated action did not. A unique but unrelated action was not memory efficient.     

Negative Cueing Effects with Weak and Strong Intralist Cues

In three experiments, we studied cueing effects of relational and itemspecific information after enacted and non-enacted encoding of short sentences (e.g. lift the pen, fold the paper). In Experiment 1, all subjects were instructed at encoding to remember only the nouns of these sentences; half of the subjects were informed about the categorical nature of the nouns, whereas the other half were not. At retrieval, all subjects were given a free recall test and a cued recall test with the verb of each sentence as the cue. In Experiment 2, all subjects were instructed at encoding to remember the whole sentence; as in Experiment 1, half of the subjects were informed about the categorical nature of the nouns and half were not. At test, all subjects were given two cued recall tests, one categorical cue for each noun in the first test and one verb cue and one categorical cue for each noun in the second test. In Experiment 3, at encoding, all subjects were informed about the categorical nature of nouns and were instructed to remember the whole sentence. In this experiment, the actions were performed with imaginary objects; free recall and cued recall tests were given to different subjects. In all three experiments, there was a negative effect of intralist cueing with verbs. This finding is at odds with the Encoding Specificity Principle, which assumes facilitation of cueing at retrieval if the cues were encoded together with the to-be-remembered information at encoding. Also, the effect of intralist cueing was different after encoding with enactment than after encoding without enactment; this difference holds true for enactment with real objects but not for enactment with imaginary objects. Enactment increased both the relational and the item-specific cueing efficiency. The results are discussed in terms of encoding interference between cues and targets and between item-specific processing and relational processing. Enacted encoding is conceived as integrating episodic information both with respect to item specificity and relational aspects of the information.     

The effect of enactment on memory for order

The effect of enactment on memory for serial order was investigated in two experiments. In both experiments a reconstruction task was used to separate order from item information. In Experiment 1 enactment and test information was manipulated between groups. For subjects who had not been informed about the reconstruction test, performance of verbal and motor groups was similar with regard to both serial-position curves and overall performance. For subjects who knew beforehand that they would be tested for memory of the order of the action events, performance in the verbal condition was significantly better than in the motor condition. In Experiment 2, the reversed enactment effect for test-informed subjects was replicated with a within-subjects design. The results agree with Engelkamp and Zimmer's (1984, 1994) position that enactment serves exclusively to enhance item information, and indicate that subjects have less control over the encoding processes when they are enacting than during verbal encoding (cf. Cohen, 1981).     

Memory of action events: the role of objects in memory of self- and other-performed tasks.

Encoding action phrases by enactment produces better recall than hearing or reading the action phrase. This study examined whether enactment enhances memory relative to observing another perform the same action. Theories of the enactment effect suggest that the complexity of the action, here manipulated by varying the number of objects involved in an action, may determine whether enactment enhances memory relative to observation. The results revealed a consistent subject-performed task advantage across all object conditions; the size of the effect did not vary with increasing task complexity. Additionally, items that included the use of an object were recalled better than those without objects. The results are consistent with the views of Engelkamp and Zimmer (1997) and Backman, Nilsson, & Kormi-Nouri (1993), who argued that the SPT effect is due to motor and/or sensory encoding.     

The effect of childhood bilingualism on episodic and semantic memory tasks

Kormi-Nouri, Moniri and Nilsson (2003) demonstrated that Swedish-Persian bilingual children recalled at a higher level than Swedish monolingual children, when they were tested using Swedish materials. The present study was designed to examine the bilingual advantage of children who use different languages in their everyday life but have the same cultural background and live in their communities in the same way as monolingual children. In four experiments, 488 monolingual and bilingual children were compared with regard to episodic and semantic memory tasks. In experiments 1 and 2 there were 144 boys and 144 girls in three school groups (aged 9-10 years, 13-14 years and 16-17 years) and in three language groups (Persian monolingual, Turkish-Persian bilingual, and Kurdish-Persian bilingual). In experiments 3 and 4, there were 200 male students in two school groups (aged 9-10 years and 16-17 years) and in two language groups (Persian monolingual and Turkish-Persian bilingual). In the episodic memory task, children learned sentences (experiments 1-3) and words (Experiment 4). Letter and category fluency tests were used as measures of semantic memory. To change cognitive demands in memory tasks, in Experiment 1, the integration of nouns and verbs within sentences was manipulated by the level of association between verb and noun in each sentence. At retrieval, a recognition test was used. In experiments 2 and 3, the organization between sentences was manipulated at encoding in Experiment 2 and at both encoding and retrieval in Experiment 3 through the use of categories among the objects. At retrieval, free recall or cued recall tests were employed. In Experiment 4, the bilingual children were tested with regard to both their first and their second language. In all four experiments, a positive effect of bilingualism was found on episodic and semantic memory tasks; the effect was more pronounced for older than younger children. The bilingual advantage was not affected by changing cognitive demands or by using first/second language in memory tasks. The present findings support the cross-language interactivity hypothesis of bilingual advantage.     

Limits on the role of retrieval cues in memory for actions: Enactment effects in the absence of object cues in the environment

Verb-object phrases (open the umbrella, knock on the table) are usually remembered better if they have been enacted during study (also called subject-performed tasks) than if they have merely been learned verbally (verbal tasks). This enactment effect is particularly pronounced for phrases for which the objects (table) are present as cues in the study and test contexts. In previous studies with retrieval cues for some phrases, the enactment effect in free recall for the other phrases has been surprisingly small or even nonexistent. The present study tested whether the often replicated enactment effect in free recall can be found if none of the phrases contains context cues. In Experiment 1, we tested, and corroborated, the suppression hypothesis: The enactment effect for a given type of phrase (marker phrases) is modified by the presence or absence of cues for the other phrases in the list (experimental phrases). Experiments 2 and 3 replicated the enactment effect for phrases without cues. Experiment 2 also showed that the presence of cues either at study or at test is sufficient for obtaining a suppression effect, and Experiment 3 showed that the enactment effect may disappear altogether if retrieval cues are very salient.     

Memory for action events: findings in neurological patients

Encoding action phrases by enacting leads normally to better memory performance than verbal encoding. In order to gain additional insight into the representational basis of the enactment effect, neurological patients are contrasted with healthy participants. Persons suffering from Parkinson's disease, which primarily impairs the motor system, and patients suffering from Frontal Lobe Syndrome, which primarily affects action-related planning processes, were involved. We investigated whether the enactment effect would be differentially affected by these disorders. In addition, the characteristics of information processing after encoding by enacting was analyzed by varying memory material (unrelated versus clusterable actions) and by adding an encoding condition that included obligatory action planning (director condition). The findings indicate that the impact of motor information for the enactment effect is not dominant compared to the role of action-related cognitive and motivational processes, in particular planning processes. The findings of the two experiments are explained within traditional conceptual memory theories.     

Memory for goal-directed sequences of actions: Is doing better than seeing?

Verb-object phrases are usually remembered better if they have been enacted during study than if theyhave been learned verbally or if one has observed another person enact the phrases. Researchers have explained this well-established enactment effect by assuming that enactment leaves an additional motor code enhancing memory. We assume instead that enactment provokes excellentitem-specific processing at t he expense of processing relations between items. Thus, if recall were to depend on this relational processing that is hindered by enactment, enactment should not be a more effective encoding strategy than observation. We tested this hypothesis by analyzing the recall of sequences of related actions. In two experiments, we found no recall advantage of enactment over observing another person perform, though both encoding tasks were superior to verbal learning. Organization was best after observation. These findings imply that learning by viewing is not inferior to learning by doing.     

动作记忆SPT优势效应的理论探讨

操作条件下的记忆效果好于语词条件下记忆效果的现象被称为动作记忆SPT效应。以往研究先后提出非策略加工、多通道加工、动作编码及情景整合理论来解释SPT效应,但这些理论解释仍存在矛盾和分歧,并阻碍了当前动作记忆领域的研究进展。为了解决目前的理论困境,本文详细地阐述了各理论的核心内容、发展历程及其存在矛盾和分歧的原因,并提出应以加工过程与加工对象相结合的视角来建立新的理论模型,以进一步促进实证研究的展开。     

Gesturing helps memory encoding in aMCI

Encoding in episodic memory is a step often impaired in patients with amnestic Mild Cognitive Impairment (aMCI). However, procedural memory processes are still relatively preserved. In line with previous research on the enactment effect, we investigated the potential benefit of encoding words combined with imitative gestures on episodic memory. Based on the Grober and Buschke’s free/cued recall procedure, we developed the Symbiosis test in which 13 patients with aMCI and 16 healthy elderly participants learned 32 words belonging to 16 different semantic categories either in a verbal encoding (A) or a bimodal (B; verbal and motor imitation) condition, using a blocked ABBA/BAAB procedure. Overall, memory retrieval was better in healthy participants than in patients with aMCI, and better for cued retrieval in the bimodal encoding (gesture cues) than the verbal encoding (category cues) condition, but there was no interaction effect between group and encoding conditions. These results show that performing concomitant gestures can enhance cued episodic memory retrieval in patients with aMCI and in healthy elderly controls. The Symbiosis test broadens the scope of the enactment effect, from action phrases to isolated words learning in patients with aMCI. Future work should investigate how bimodal encoding provides novel perspectives for memory rehabilitation in patients with aMCI.     

Memory for actions: Self-performed tasks and the reenactment effect

Encoding action phrases by enactment (self-performed tasks, or SPTs) leads to better memory than does observing actions (experimenter-performed tasks, or EPTs) or hearing action phrases (Engelkamp, 1998). In addition, recognition memory for SPTs is enhanced when test items are reenacted. Experiment 1 demonstrated a reenactment effect for EPTs, as well as for SPTs, indicating that the effect can be based on visual, as well as motoric, feedback. However, the reenactment effect in SPTs was found even when the participants were blindfolded at test (Experiment 2), indicating that the basis for the reenactment effect differs across SPTs and EPTs. Experiments 3 and 4 provided additional evidence that visual feedback is not critical for reenactment recognition in the case of SPTs. In addition, these experiments failed to show a hand congruency effect (enhanced recognition when the same hand enacts at study and at test), indicating that this effect is not as generalizable as the reenactment effect. These results have important implications for the motor-encoding hypothesis of the enactment effect.     

The role of enactment in implicit and explicit memory

Enactment during the encoding of simple imperatives has been found to improve substantially performance on conceptually driven explicit-memory tests. In two experiments the effect of this manipulation on a conceptually driven implicit test (category association) was studied. A conceptually driven explicit test (free recall) was also included. In Experiment one three different study conditions (enactment with real objects, reading, and generation) were considered. In Experiment two there were two study conditions (enactment with imaginary objects and reading). Compared to reading, generation was found to improve the performance on both free recall and category association, whereas enactment affected free recall only. In a final experiment subjects imagined that they performed the tasks, and this manipulation was found to improve the memory performance on both tests. Taken together, this pattern of results is interpreted as suggesting that free recall and category association have a process in common that is sensitive to semantic processing at study (promoted by generation and imagery, but not by enactment), and that free recall involves a retrieval process in addition that is facilitated by a rich encoding environment (provided by enactment).     

Failures of retrieval and comparison constrain change detection in natural scenes

In a change detection paradigm, a target object in a natural scene either rotated in depth, was replaced by another object token, or remained the same. Change detection performance was reliably higher when a target postcue allowed participants to restrict retrieval and comparison processes to the target object (Experiment 1). Change detection performance remained excellent when the target object was not attended at change (Experiment 2) and when a concurrent verbal working memory load minimized the possibility of verbal encoding (Experiment 3). Together, these data demonstrate that visual representations accumulate in memory from attended objects as the eyes and attention are oriented within a scene and that change blindness derives, at least in part, from retrieval and comparison failure.     

Structuring the Acquisition and Retrieval Environment to Facilitate Learning in Individuals with Dementia of the Alzheimer Type

Three experiments using variations of the Subject Performed Task (SPT) paradigm examined whether structuring the learning and retrieval environment would improve learning in individuals with mild to moderate dementia of the Alzheimer type (DAT). Experiment 1 examined the role of enactment at encoding and retrieval, and found that with appropriate retrieval support DAT volunteers do benefit from enactment at encoding. Experiment 2 showed that recall was further enhanced when the list of SPTs formed a cohesive, goal-directed sequence of actions. In Experiment 3, DAT subjects acquired a more complex action-based sequence and maintained it accurately over a short period of time. It is concluded that the provision of contextual support at encoding and at retrieval can enhance residual memory in individuals with DAT.     

Encoding information for future action: Memory for to-be-performed tasks versus memory for to-be-recalled tasks

What is the nature of the representation underlying memory for future tasks such as calling the doctor or buying milk? If this representation consists of a verbal instruction that is translated into action at the time of retrieval, then memory should be better when tested via verbatim recall of the instruction than when tested via actual performance. Three experiments rejected this possibility, indicating better memory for a perform mode of report than for a recall mode of report. This was true in Experiment 1 in which subjects saw a series of verbal instructions (e.g., “move the eraser,” “lift the cup,” “touch the ashtray”), with advance information regarding the mode of report required during testing. In Experiment 2, the advance cue was valid only in 75% of the trials. Memory depended more heavily on the expected mode of report thanon the actual mode ofreport, suggesting that the perform superiority is due to processes that occur during encoding. In Experiment 3, subjects learned 20 phrases depicting minitasks were remembered by subjects tested via performance than by subjects tested via verbatim recall. A second part of Experiment 3 also indicated superior memory when a perform test was expected, regardless of which mode of report was actually required. The results were compared with the finding that subject-performed tasks are better remembered thanare their verbal instructions, which suggeststhat the representation underlying memory for future assignments-may-take advantage of the imaginal-enactive properties ofthe envisagedacts. Other possible differences between memory for to-be-recalled tasks and memory for to-be-performed tasks are discussed.     

A motor isolation effect: When object manipulability modulates recall performance

Previous studies suggested that the language production architecture is recruited during verbal retention, and others proposed that spatial memory relies on the oculomotor system. The objective of the present study was to investigate the role of the motor system in object memory, by examining the effect of objects' affordances on retention. In a serial recall task, we manipulated the manipulability of objects to retain in memory. We used an isolation paradigm where we isolated the manipulability level of one object from the list. We showed that recall performance improved for the isolated object (Experiment 1) and that this advantage was abolished when participants were required to perform motor suppression during the task (Experiment 2). In Experiment 3, we showed that the abolition of the motor isolation effect in Experiment 2 was not due to an effect of distraction since motor suppression was shown not to interfere with a semantic isolation effect. It is argued that motor affordances play a role in object memory, but only when the motor characteristics of an object allow discriminating it from the other objects in the list.     

Relevance of the listener’s motor system in recalling phrases enacted by the speaker

Memory for series of action phrases improves in listeners when speakers accompany each phrase with congruent gestures compared to when speakers stay still. Studies reveal that the listeners’ motor system, at encoding, plays a crucial role in this enactment effect. We present two experiments on gesture observation, which explored the role of the listeners’ motor system at recall. The participants listened to the phrases uttered by a speaker in two conditions in each experiment. In the gesture condition, the speaker uttered the phrases with accompanying congruent gestures, and in the no-gesture condition, the speaker stayed still while uttering the phrases. The participants were then invited, in both conditions of the experiments, to perform a motor task while recalling the phrases proffered by the speaker. The results revealed that the advantage of observing gestures on memory disappears if the listeners move at recall arms and hands (same motor effectors moved by the speaker, Experiment 1a), but not when the listeners move legs and feet (different motor effectors from those moved by the speaker, Experiment 1b). The results suggest that the listeners’ motor system is involved not only during the encoding of action phrases uttered by a speaker but also when recalling these phrases during retrieval.     

Improved episodic integration through enactment: implications for aging

Enactment may improve memory for verb phrases by facilitating episodic integration of object-action components into a unitized whole. It is unclear, however, whether the influence of enactment on episodic integration is related to or independent of the strength of the preexisting semantic relationship between components. To address this issue, the authors examined the influence of enactment on memory for lists of semantically related object-action phrases ("Put money in the wallet") and semantically unrelated phrases created by repairing these objects and actions to make phrases that were unusual but still were possible to perform ("String a thread through the wallet," "Put money in the napkin"). As such, phrases in the related and unrelated lists were matched for familiarity of the individual components and differed only in the associative strength of the object-action relationship. Although verbatim recall of unrelated lists was poorer under standard verbal encoding conditions, enactment succeeded in bringing performance to the level of related lists, indicating that enactment's influence on episodic integration was independent of the semantic relatedness of the object and action components. Analysis of partial recall errors (accurate recall of only one component) suggested that enactment benefited recall in the unrelated lists by improving memory for the action and reducing fragmentation of the association, providing further support for the unitization view. This pattern of results was replicated in normal older adults, a population that exhibits particular difficulty with episodic memory for unrelated associations. The cognitive mechanisms by which enactment may improve episodic integration in both younger and older adults are discussed.