Memory as a scale of simulation depending on the trace distinctiveness.

It has been proposed that representations emerge from a single memory system organized along a continuum of specificity. This continuum is assumed to reflect a scale between the simulation of overlapping and specific features of the traces, which depends on trace distinctiveness. More specifically, higher trace distinctiveness facilitates the simulation of trace-specific features, which increase the discriminability of traces and lead to the emergence of a more specific representation. In two experiments, participants were asked to identify match (low task discrimination demand) or mismatch (high task discrimination demand) associations between actions and characters that were visually either highly or lowly distinctive. The results of Experiment 1 show that in the high-distinctiveness context, performance was better when identifying a mismatch rather than a match, while the opposite was true in the low-distinctiveness context. The results of Experiment 2 show that using a dynamic visual noise to interfere with the participants' ability to simulate the features of the characters also reduced the benefit of the high-distinctiveness context for the mismatch trials (Experiment 2a and 2b) and increased the benefit of the low-distinctiveness context for the match trials (Experiment 2b). Taken together, these results suggest that the simulation of trace-specific features underlies the emergence of specific representations, which can be beneficial when the discrimination demand of the task is high and detrimental when this demand is low. Memory might therefore be viewed as a scale of simulation between overlapping and specific trace features.

Temporal Predictions in Space: Isochronous Rhythms Promote Forward Projections of the Body.

A regular rhythmic stimulation increases people's ability to anticipate future events in time and to move their body in space. Temporal concepts are usually prescribed to spatial locations through a past-behind and future-ahead mapping. In this study, we tested the hypothesis that a regular rhythmic stimulation could promote the forward-body (i.e., toward the future) projections in the peri-personal space. In a Visual Approach/Avoidance by the Self Task (VAAST), participants (N = 24) observed a visual scene on the screen (i.e., a music studio with a metronome in the middle). They were exposed to 3 s of auditory isochronous or non-isochronous rhythms, after which they were asked to make as quickly as possible a perceptual judgment on the visual scene (i.e., whether the metronome pendulum was pointing to the right or left). The responses could trigger a forward or backward visual flow, i.e., approaching or moving them away from the scene. Results showed a significant interaction between the rhythmic stimulation and the movement projections (p < 0.001): participants were faster for responses triggering forward-body projections (but not backward-body projections) after the exposure to isochronous (but not non-isochronous) rhythm. By highlighting the strong link between isochronous rhythms and forward-body projections, these findings support the idea that temporal predictions driven by a regular auditory stimulation are grounded in a perception-action system integrating temporal and spatial information.

Playing "guess who?": when an episodic specificity induction increases trace distinctiveness and reduces memory errors during event reconstruction.

The constructive nature of memory implies a possible confusion between details of similar events. Memory interventions should thus target the reduction of memory errors. We postulate that a brief intervention called Episodic Specificity Induction (ESI) facilitates the sensorimotor simulation of event-related details by improving the distinctiveness of the event memory trace. As such, ESI should reduce memory errors only when event memory traces are strongly overlapping based on their sensorimotor features. Participants memorised videos showing characters performing an action on a given object. The characters were either visually very similar to each other or very distinct (low vs. high distinctiveness condition). Next, participants performed either an imagination version of the ESI or a control induction. Finally, a voice announced one of the actions seen and a character was then briefly displayed. The participants had to indicate whether the association was correct. For incorrect associations, in the low distinctiveness condition, false alarms were more likely than in the high distinctiveness condition and were reduced after the ESI. It suggests that facilitating the simulation of specific details through the ESI increased trace distinctiveness and reduced memory errors at the critical time of event reconstruction. Future clinical applications might be possible.

Validation of New Methods of Using Simulated Whole-Body Movements as Implicit Indicators of Sound and Odor Preferences.

Would you get close to a stinky perfume bottle or to a loudspeaker producing noise? In this paper, we present two procedures that allowed us to assess the ability of auditory and olfactory cues to elicit automatic approach/avoidance reactions toward their sources. The procedures resulted from an adaptation of the Visual Approach/Avoidance by the Self Task (VAAST; Rougier et al., 2018), a task having the peculiarity of simulating approach/avoidance reactions by using visual feedback coming from the whole-body movements. In the auditory VAAST (Experiment 1), participants were instructed to move forward or backward from a loudspeaker that produced spoken words differentiated by their level of distortion and thus by their hedonic value. In the olfactory VAAST (Experiment 2), participants were asked to move forward or backward from a perfume bottle that delivered pleasant and unpleasant odors. We expected, consistent with the approach/avoidance compatibility effect, shorter latencies for approaching positive stimuli and avoiding negative stimuli. In both experiments, we found an effect of the quality of the emotional stimulus on forward actions of participants, with undistorted words and pleasant odors inducing faster forward movements compared with that for distorted words and unpleasant odors. Notably, our results further suggest that the VAAST can successfully be used with implicit instructions, i.e., without requiring participants to explicitly process the valence of the emotional stimulus (in Experiment 1) or even the emotional stimulus itself (in Experiment 2). The sensitivity of our procedures is analyzed and its potential in cross-modal and (contextualized) consumer research discussed.

Spatial sonification of letters on tablets to stimulate literacy skills and handwriting in 5 y-o children: A pilot study.

We evaluate the effects of multisensory training on letters, including sonification of graphic symbols. We used "spatial sonification" where letter handwriting movements recorded in a two dimensional plan, vertical and horizontal, are systematically assigned to two acoustic features, spectral composition for the horizontal axis and frequency for the vertical axis. Forty-six kindergarten children were recruited. They were randomly assigned to three multisensory training groups: with sonification (Son) of letters, with a melody unrelated to the shape of the letters (Mel) and without any sound (Sil). We observed a significant effect of training, with the Son group performing better than the other groups in the reading and spelling tasks. We also observed a modification of two kinematic cues (time and in-air time) during handwriting, also in the Son group. We conclude that letter sonification could act as a binder between the visual and auditory dimensions of the letter. The processes underlying this benefit are discussed in the light of the Act-In model, a cognition memory model.

Distinctive Effects of Within-Item Emotion Versus Contextual Emotion on Memory Integration.

This study investigates the links between memory and emotion and, more specifically, how emotions can impact the integration mechanism. The authors' hypotheses were based on a dynamic conception of memory (Versace et al., 2014; Macri et al., 2018), and stated that an emotion coming from the stimulus (within-item emotion) should enhance the integration of the stimulus features, and that an emotion coming from the context (contextual emotion) should improve integration of the item and its context. In two experiments, the participants performed an associative memory task in which they undertook three kinds of recall: item (memory for a target item), location (spatial position of a target item), and association recall (association of a target item and its location). In the first experiment, the emotion was introduced by the target stimuli (neutral or negative words), while in the second experiment, contextual emotion was introduced by means of an odorant dispenser (negative or neutral odorant) placed under the participant's chin and only neutral words were used. In both experiments, target items were words objects or animals that were either typically associated to a sound or not typically associated to a sound). The results confirm that emotions act in different ways on the integration mechanism depending on how they are introduced to the participant: within-item emotion enhances item recall itself by strengthening the link between its components, while contextual emotion favors the integration of the item with its location.

"Does It Improve the Mind's Eye?": Sensorimotor Simulation in Episodic Event Construction.

Memories are not frozen in the past. Instead, they can be dynamically combined to allow individuals to adapt to the present or even imagine the future. This recombination, called event construction, also means that it might be possible to improve memory through specific interventions such as episodic specificity induction (ESI). ESI provides brief training in recollecting the details of a past event that boosts the retrieval of specific details in subsequent tasks if these tasks involve the recombination of memories. However, very little is known about how event construction is accomplished, and this is essential if we are (1) to understand how episodic memory might work and (2) to promote a specific mechanism that will help people remember the past better. The present study assesses the sensorimotor simulation hypothesis, which has been proposed within the embodied approaches to cognition. According to these approaches, access to and the recombination of memories occur through the simulation of the sensory and motor propreties of our past experiences. This hypothesis was tested using a sensory interference paradigm. In a first phase, the participants watched videos and then received a specificity or a control induction. In a second phase, they described their memories of the videos while simultaneously viewing an interfering stimulus (dynamic visual noise; DVN) or a gray control screen. In line with a sensorimotor simulation account, the presentation of a DVN during the description of the videos led to a decrease in the number of internal details (details specific to the event) only after the specificity induction rather than the control induction. The findings provide evidence that the specificity induction targets and facilitates the sensorimotor simulation mechanism, thus confirming the crucial involvement of a mechanism of this sort in the constructive functioning of memory.

When a Reactivated Visual Mask Disrupts Serial Recall.

To prevent forgetting in working memory, the attentional refreshing is supposed to increase the level of activation of memory traces by focusing attention. However, the involvement of memory traces reactivation in refreshing relies in the majority on indirect evidence. The aim of this study was to show that refreshing relies on the reactivation of memory traces by investigating how the reactivation of an irrelevant trace prevents the attentional refreshing to take place, and (2) the memory traces reactivated are sensorial in nature. We used a reactivated visual mask presented during the encoding (Experiment 1) and the refreshing (Experiment 2) of pictures in a complex span task. Results showed impaired serial recall performance in both experiments when the mask was reactivated compared to a control stimulus. Experiment 3 confirmed the refreshing account of these results. We proposed that refreshing relies on the reactivation of sensory memory traces.

Sleep on your memory traces: How sleep effects can be explained by Act-In, a functional memory model.

Numerous studies have explored the effect of sleep on memory. It is well known that a period of sleep, compared to a similar period of wakefulness, protects memories from interference, improves performance, and might also reorganize memory traces in a way that encourages creativity and rule extraction. It is assumed that these benefits come from the reactivation of brain networks, mainly involving the hippocampal structure, as well as from their synchronization with neocortical networks during sleep, thereby underpinning sleep-dependent memory consolidation and reorganization. However, this memory reorganization is difficult to explain within classical memory models. The present paper aims to describe whether the influence of sleep on memory could be explained using a multiple trace memory model that is consistent with the concept of embodied cognition: the Act-In (activation-integration) memory model. We propose an original approach to the results observed in sleep research on the basis of two simple mechanisms, namely activation and integration.

The beneficial effect of contextual emotion on memory: the role of integration.

This study investigates the effects of emotion on the integration mechanism which binds together the components of an event and the relations between these components and encodes them within a memory trace [Versace, R., Vallet, G. T., Riou, B., Lesourd, M., Labeye, É, & Brunel, L. (2014). Act-In: An integrated view of memory mechanisms. Journal of Cognitive Psychology, 26(3), 280-306. doi: 10.1080/20445911.2014.892113 ]. Based on the literature, the authors argue that, in a memory task, contextual emotion could strengthen the integration mechanism and, more specifically, the relations between a target item and its contextual features. To test this hypothesis, the authors used two odorants (neutral and negative) to compare the effects of a negative context with those of a neutral one on three different types of recall: item recall (memory for pictures objects), source recall (spatial position of the pictures in a matrix) and recall of the association between an item and its location. The results showed that, in the negative odour context, association recall and source recall - but not item recall - were better than in the neutral odour context thus confirming the effect of emotion on integration. The results lead to the hypothesis that the effects of emotion on memory are linked to the way emotion is introduced into the experimental settings: via the items to be memorised or via the context.

Haptic modality takes its time: Dynamic of activations of sensory modalities in perceptual and memory processes.

Based on claims resulting from grounded cognition theory that perceptual and memory processes are using the same distributed systems, the present study investigated the temporal aspect of access to memory traces through haptic and auditory modalities. Unlike in the case of visual or auditory components, the perception of a vibrotactile component is more sequential in nature and therefore cannot be fully processed before the end of the signal. The present study explores the dynamic of components activation in a situation of audio-vibrotactile asynchrony. We used a short-term priming paradigm consisting of an association phase (between a vibration and sound) and a test phase testing priming effect of a vibrotactile stimulation on the processing of a target sound. Results showed an interference with a simultaneous processing and a facilitation with a sequential processing. The temporality process of perceptual components is also important at a memory level.

A SEMantic and EPisodic Memory Test (SEMEP) Developed within the Embodied Cognition Framework: Application to Normal Aging, Alzheimer's Disease and Semantic Dementia.

Embodiment has highlighted the importance of sensory-motor components in cognition. Perception and memory are thus very tightly bound together, and episodic and semantic memories should rely on the same grounded memory traces. Reduced perception should then directly reduce the ability to encode and retrieve an episodic memory, as in normal aging. Multimodal integration deficits, as in Alzheimer's disease, should lead to more severe episodic memory impairment. The present study introduces a new memory test developed to take into account these assumptions. The SEMEP (SEMantic-Episodic) memory test proposes to assess conjointly semantic and episodic knowledge across multiple tasks: semantic matching, naming, free recall, and recognition. The performance of young adults is compared to healthy elderly adults (HE), patients with Alzheimer's disease (AD), and patients with semantic dementia (SD). The results show specific patterns of performance between the groups. HE commit memory errors only for presented but not to be remembered items. AD patients present the worst episodic memory performance associated with intrusion errors (recall or recognition of items never presented). They were the only group to not benefit from a visual isolation (addition of a yellow background), a method known to increase the distinctiveness of the memory traces. Finally, SD patients suffer from the most severe semantic impairment. To conclude, confusion errors are common across all the elderly groups, whereas AD was the only group to exhibit regular intrusion errors and SD patients to show severe semantic impairment.

The automatic visual simulation of words: A memory reactivated mask slows down conceptual access.

How do we represent the meaning of words? The present study assesses whether access to conceptual knowledge requires the reenactment of the sensory components of a concept. The reenactment-that is, simulation-was tested in a word categorisation task using an innovative masking paradigm. We hypothesised that a meaningless reactivated visual mask should interfere with the simulation of the visual dimension of concrete words. This assumption was tested in a paradigm in which participants were not aware of the link between the visual mask and the words to be processed. In the first phase, participants created a tone-visual mask or tone-control stimulus association. In the test phase, they categorised words that were presented with 1 of the tones. Results showed that words were processed more slowly when they were presented with the reactivated mask. This interference effect was only correlated with and explained by the value of the visual perceptual strength of the words (i.e., our experience with the visual dimensions associated with concepts) and not with other characteristics. We interpret these findings in terms of word access, which may involve the simulation of sensory features associated with the concept, even if participants were not explicitly required to access visual properties. (PsycINFO Database Record

The Reactivation of Motion influences Size Categorization in a Visuo-Haptic Illusion.

People simulate themselves moving when they view a picture, read a sentence, or simulate a situation that involves motion. The simulation of motion has often been studied in conceptual tasks such as language comprehension. However, most of these studies investigated the direct influence of motion simulation on tasks inducing motion. This article investigates whether a mo- tion induced by the reactivation of a dynamic picture can influence a task that did not require motion processing. In a first phase, a dynamic picture and a static picture were systematically presented with a vibrotactile stimulus (high or low frequency). The second phase of the experiment used a priming paradigm in which a vibrotactile stimulus was presented alone and followed by pictures of objects. Participants had to categorize objects as large or small relative to their typical size (simulated size). Results showed that when the target object was preceded by the vibrotactile stimulus previously associated with the dynamic picture, participants perceived all the objects as larger and categorized them more quickly when the objects were typically "large" and more slowly when the objects were typically "small." In light of embodied cognition theories, this bias in participants' perception is assumed to be caused by an induced forward motion. generated by the reactivated dynamic picture, which affects simulation of the size of the objects.

Memory plays tricks on me: perceptual bias induced by memory reactivated size in Ebbinghaus illusion.

The relationship between perceptual and memory processing is at the core of cognition. Growing evidence suggests reciprocal influences between them so that memory features should lead to an actual perceptual bias. In the present study, we investigate the reciprocal influence of perceptual and memory processing by further adapting the Ebbinghaus illusion and tested it in a psychophysical design. In a 2AFC (two-alternative forced choice) paradigm, the perceptual bias in the Ebbinghaus illusion was induced by a physical size (Experiment 1) or a memory reactivated size of the inducers (Experiment 2, the size was reactivated thanks to a color-size association). One test disk was presented on the left of the screen and was surrounded by six inducers with a large or small (perceptual or reactivated) size. The test disk varied in size and participants were asked to indicate whether this test disk was smaller or larger than a reference disk presented on the right of the screen (the reference disk was invariant in size). Participants' responses were influenced by the size of the inducers for the perceptual and the reactivated size of the inducers. These results provide new evidence for the influence of memory on perception in a psychophysics paradigm.

Manipulation gesture effect in visual and auditory presentations: the link between tools in perceptual and motor tasks.

There is much behavioral and neurophysiological evidence in support of the idea that seeing a tool activates motor components of action related to the perceived object (e.g., grasping, use manipulation). However, the question remains as to whether the processing of the motor components associated with the tool is automatic or depends on the situation, including the task and the modality of tool presentation. The present study investigated whether the activation of motor components involved in tool use in response to the simple perception of a tool is influenced by the link between prime and target tools, as well as by the modality of presentation, in perceptual or motor tasks. To explore this issue, we manipulated the similarity of gesture involved in the use of the prime and target (identical, similar, different) with two tool presentation modalities of the presentation tool (visual or auditory) in perceptual and motor tasks. Across the experiments, we also manipulated the relevance of the prime (i.e., associated or not with the current task). The participants saw a first tool (or heard the sound it makes), which was immediately followed by a second tool on which they had to perform a perceptual task (i.e., indicate whether the second tool was identical to or different from the first tool) or a motor task (i.e., manipulate the second tool as if it were the first tool). In both tasks, the similarity between the gestures employed for the first and the second tool was manipulated (Identical, Similar or Different gestures). The results showed that responses were faster when the manipulation gestures for the two tools were identical or similar, but only in the motor task. This effect was observed irrespective of the modality of presentation of the first tool, i.e., visual or auditory. We suggest that the influence of manipulation gesture on response time depends on the relevance of the first tool in motor tasks. We discuss these motor activation results in terms of the relevance and demands of the tasks.

Sensory-motor properties of past actions bias memory in a recognition task.

The aim of this study was to show that sensory-motor consequences of past actions form part of memory trace components cued by current experience. In a first task participants had to learn a list of words. Then in a guessing task they played against the computer. Finally, in a recognition task, they had to judge if the words were or were not present in the learning task. Words appeared either in the colour associated with success or failure in the guessing task, or in a non-informative colour. In the first experiment, results show that when the words to be judged were in the colour associated with success, participants answered faster and produced more "old" responses than when the words to be judged were in the colour associated with failure in the previous task. Moreover, when the words to be judged were in the colour associated with failure, participants were slower and produced less "old" responses than when the words were in a colour not informative of success or failure. The second experiment confirms that the results obtained in Experiment 1 were linked to the sensory-motor consequences of past actions associated with the colour and not to the colour itself.

Perceptual processing affects the reactivation of a sensory dimension during a categorization task.

According to grounded theories of cognition, knowledge is grounded in its sensory-motor features. Therefore, perceptual and conceptual processing should be based on the same distributed system so that conceptual and perceptual processes should interact. The present study assesses whether gustatory stimulation (participants tasted a sweet or a nonsweet yoghurt) could influence performance on a categorization task that involves the reactivation of the same sensory dimension. The results indicate that participants were slower (Experiment 1) or faster (Experiment 2), respectively, at categorizing pictures as representing edible sweet stimuli when they either simultaneously or had previously tasted a sweet yoghurt as compared to a nonsweet yoghurt. These results confirm the significant overlap between perceptual and memory mechanisms and suggest the functional equivalence between perceptually present and perceptually absent (memory reactivated) dimensions.

"The mask who wasn't there": visual masking effect with the perceptual absence of the mask.

Does a visual mask need to be perceptually present to disrupt processing? In the present research, we proposed to explore the link between perceptual and memory mechanisms by demonstrating that a typical sensory phenomenon (visual masking) can be replicated at a memory level. Experiment 1 highlighted an interference effect of a visual mask on the categorization of auditory targets and confirmed the multimodal nature of knowledge. In Experiment 2, we proposed to reactivate this mask in a categorization task on visual targets. Results showed that the sensory mask has disrupted (slower reaction times) the processing of the targets whether the mask was perceptually present or reactivated in memory. These results support a sensory-based conception of memory processing and suggest that the difference between perceptual processes and memory processes is characterized by the presence (perception) or the absence (memory) of the sensory properties involved in the activity.

Demonstration of an ebbinghaus illusion at a memory level: manipulation of the memory size and not the perceptual size.

Based on recent behavioral and neuroimaging data suggesting that memory and perception are partially based on the same sensorimotor system, the theoretical aim of the present study was to show that it is difficult to dissociate memory mechanisms from perceptual mechanisms other than on the basis of the presence (perceptual processing) or absence (memory processing) of the characteristics of the objects involved in the processing. In line with this assumption, two experiments using an adaptation of the Ebbinghaus illusion paradigm revealed similar effects irrespective of whether the size difference between the inner circles and the surrounding circles was manipulated perceptually (the size difference was perceptually present, Experiment 1) or merely reactivated in memory (the difference was perceptually absent, Experiment 2).