The applied value of collaborative memory research in aging: Behavioral and neural considerations

Our aim in this paper is to bring attention to the applied value of collaborative memory research in aging. At this time, much collaborative memory research focuses on the negative effects of collaboration in younger adults, and is primarily basic in nature. Here, we highlight the positive effects of collaboration that have received less attention, with a particular emphasis on the applied value of these effects in older adults. We first review studies to show that recalling in a group improves later individual recall and reduces memory errors in older adults. We then outline a four-step approach towards bridging laboratory and applied collaborative memory research, which involves: (1) complementing traditional paradigms with more ecologically valid paradigms, (2) evaluating these paradigms in applied settings, (3) adapting these paradigms for use with cognitively intact and cognitively impaired populations, and (4) modifying these paradigms to examine the neural systems that operate during collaborative recall.     

Encoding strategy affects false recall and recognition: Evidence from categorical study material

The present research investigated memory vulnerability to distortions. Different encoding strategies were used when categorized lists were studied. The authors assumed that an imagery strategy would be responsible for decreasing false memories more than a word-whispering strategy, which is consistent with the model of semantic access and previous research in the Deese-Roediger-McDermott paradigm (the DRM paradigm; Deese, 1959; Roediger & McDermott, 1995). A normative study of category lists and 4 experiments were conducted to verify the memory vulnerability to different encoding strategies (imagery, word-whispering, control). Half of subjects recalled and half recognized previously studied words. The results revealed a marked reduction in false recognition and recall after imagery encoding, relative to after word-whispering encoding.     

Motor simulation in verbal knowledge acquisition

Recent research highlights the importance of motor processes for a wide range of cognitive functions such as object perception and language comprehension. It is unclear, however, whether the involvement of the motor system goes beyond the processing of information that is gathered through active action experiences and affects also the representation of knowledge acquired through verbal learning. We tested this prediction by varying the presence of motor interference (i.e., squeezing a ball vs. oddball detection task) while participants verbally acquired functional object knowledge and examined the effects on a subsequent object detection task. Results revealed that learning of functional object knowledge was only impaired when participants performed an effector-specific motor task while training. The present finding of an effector-specific motor interference effect on object learning demonstrates the crucial role of the motor system in the acquisition of novel object knowledge and provides support for an embodied account to perception and cognition.     

Generation disrupts memory for intrinsic context but not extrinsic context

Although generation typically enhances item memory, the effect is subject to a number of theoretically important limitations. One potential limitation concerns context memory but there has been debate about whether generation actually enhances or disrupts memory for contextual details. Five experiments assessed the effect of generation on context memory for perceptual attributes of the study stimulus (intrinsic context). The results indicate that despite enhancing item memory, generation disrupts memory for intrinsic context. This result generalized over different intrinsic details (print colour and font), different generation manipulations, and several methodological factors identified in earlier research as potential moderators of this negative generation effect. Despite the negative generation effect on intrinsic context, contextual details external to the target item (extrinsic context) are not disrupted. In a sixth experiment, a visually based generation task (letter transposition) enhanced context memory for the extrinsic detail of location. Coupled with earlier research, the results indicate that generation disrupts context memory for intrinsic details but either does not harm or enhances memory for extrinsic context.     

Consensus collaboration enhances group and individual recall accuracy

We often remember in groups, yet research on collaborative recall finds “collaborative inhibition”: Recalling with others has costs compared to recalling alone. In related paradigms, remembering with others introduces errors into recall. We compared costs and benefits of two collaboration procedures—turn taking and consensus. First, 135 individuals learned a word list and recalled it alone (Recall 1). Then, 45 participants in three-member groups took turns to recall, 45 participants in three-member groups reached a consensus, and 45 participants recalled alone but were analysed as three-member nominal groups (Recall 2). Finally, all participants recalled alone (Recall 3). Both turn-taking and consensus groups demonstrated the usual pattern of costs during collaboration and benefits after collaboration in terms of recall completeness. However, consensus groups, and not turn-taking groups, demonstrated clear benefits in terms of recall accuracy, both during and after collaboration. Consensus groups engaged in beneficial group source-monitoring processes. Our findings challenge assumptions about the negative consequences of social remembering.     

Bartlett's schema theory: The unreplicated “portrait d'homme” series from 1932

In 1932, Frederic Bartlett laid the foundation for the later schema theory. His key assumption of previous knowledge affecting the processing of new stimuli was illustrated in the famous “portrait d'homme” series. Sequenced reproductions of ambiguous stimuli showed progressive object-likeness. As Bartlett pointed out, activation of specific schemata, for instance “the face schema”, biases memory retrieval towards such schemata. In five experiments (Experiment 1, n?=?53; Experiment 2, n?=?177; Experiment 3, n?=?36; Experiment 4, n?=?6; Experiment 5, n?=?2), we tested several factors potentially influencing retrieval biases—for example, by varying the general procedure of reproduction (repeated vs. serial) and by omitting versus providing visual or semantic cues for activating face schemata. Participants inspected face-like stimuli with the caption “portrait of the human” and reproduced them repeatedly under specific conditions. None of the experiments revealed a systematic tendency towards Bartlett's described case, even when the participants were explicitly instructed to draw “a face” like the previously inspected one. In one of the “serial reproduction” experiments, we even obtained contrary effects with decreasing face-likeness over the reproduction generations. A close analysis of the original findings raises questions about the replicability of Bartlett's findings, qualifying the “portrait d'homme” series more or less as an illustrative example of the main idea of reconstructive memory.     

Visual working memory is enhanced by mixed strategy use and semantic coding

Visual working memory is enhanced by processes related to verbalisation. However, the mechanism underlying this enhancement is unclear. Experiment 1 investigated the potential contribution of the phonological loop of working memory, by assessing the effects of articulatory suppression on two versions of the Visual Patterns Test—one low and one high in availability of verbal coding. The lack of interaction suggested that the phonological loop is not responsible; however, active use of combined verbal and visual strategies, as well as activated semantic knowledge, both appear to be related to increased capacity. Experiment 2 assessed the role of central executive resources. Because central executive suppression removed the benefit of the high verbal coding task version, central executive resources, assumed to relate to the temporary maintenance of multimodal codes in the episodic buffer, appear to underlie the benefit associated with verbalisation.     

Temporal cue–target overlap is not essential for backward inhibition in task switching

Lag 2 repetition costs are a performance cost observed when participants return to a task after just one intervening trial of a different task, compared to returning after a longer interval (AB A vs. CB A sequences, where A, B, C are tasks). This effect is known as backward inhibition (BI) and is thought to reflect the need to overcome inhibition applied specifically to Task “A” during disengagement at trial n – 1. Druey and Hübner (2007) Druey, M. and Hübner, R. 2007. The role of temporal cue–target overlap in backward inhibition under task switching. Psychonomic Bulletin & Review, 14: 749–754. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar] have suggested that employment of such a specific inhibitory mechanism relies upon the cue and the target of the task overlapping temporally. We provide evidence across three experiments (including a direct replication attempt) that this is not the case, and that the presence of task-specific BI relies to some extent on the need to translate the cue–target relationship into working memory. Additionally, we provide evidence that faster responses in no overlap conditions are driven by low-level perceptual differences between target displays across overlap conditions. We conclude that BI is an effective sequential control mechanism, employed equally in cases of temporally overlapping and temporally separated cues and targets.