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La maladie d'Alzheimer se manifeste par des troubles de la mémoire et un déclin cognitif plus général, le plus souvent associés à des troubles de l'humeur et du comportement. Les traitements médicamenteux ayant une efficacité assez modeste, il apparaît nécessaire de leur associer une prise en charge non pharmacologique. La méditation de pleine conscience, qui a des effets bénéfiques sur le fonctionnement cognitif et sur l'état émotionnel, semble être une piste intéressante. Cette revue de littérature narrative se propose de recenser les études ayant testé l'efficacité d'une intervention basée sur la pleine conscience auprès de personnes souffrant de la maladie d'Alzheimer ou à risque de développer cette maladie. Il apparaît que ces interventions présentent un intérêt pour réduire les symptômes cognitifs (troubles attentionnels et mnésiques notamment) et émotionnels (affects dépressifs et anxiété en particulier). Cependant, elles nécessitent un certain nombre de modifications pour être adaptées à ce public.

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We reviewed studies that have specifically explored the memory deficit hypothesis of Obsessive Compulsive Disorder (OCD) checking, highlighting the methodological differences between these studies that may explain inconsistencies regarding memory deficits in OCD checkers. Based on Conway's proposition that one function of episodic memories is to keep an adaptive record of recent goal processing in order to check that actions have actually been accomplished, we suggest that impaired autonoetic consciousness -one of the main features of episodic memory- may be at the heart of the issue of checking compulsion. Autonoetic consciousness, that can be experimentally assessed by the Remember/Know/Guess paradigm,could be impaired in OCD checkers leading them to be unable to mentally relive their actions in order to be assured that they have been accomplished (e.g., having locked the door). We make methodological suggestions to improve the assessment of autonoetic consciousness deficit in OCD checkers and understand its role in the etiology and maintenance of compulsive checking.

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Intrusive traumatic recollections suggest an inability in Posttraumatic Stress Disorder (PTSD) to control and notably to inhibit memories for trauma-related information. Supported by inhibitory deficits found on experimental settings in PTSD, memory functioning and memory biases in the disorder were usually explained through inhibitory and control deficits in the processing of trauma-related information. The present study aimed to directly assess this hypothesis by investigating memory control abilities for emotional information in PTSD. For this purpose, 34 patients diagnosed with PTSD were compared to 37 non-PTSD controls on an item-cued directed forgetting paradigm for emotional words combined with a Remember/Know recognition procedure. Results revealed enhanced amounts of Remember recognitions for trauma-related words in PTSD. Moreover, we replicated findings of memory control impairments in the disorder. However, such impairments only occurred for non-trauma-related words. Accordingly, it appeared that PTSD patients presented preserved memory control abilities for trauma-related words, at the expenses of other emotional valences. Surprisingly, PTSD patients presented a preserved ability to control and notably to inhibit their memory functioning for trauma-related material. In addition to potential theoretical and clinical relevance, these results are discussed in the light of resource reallocation hypotheses and vigilant-avoidant theories of information processing in PTSD.

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The present study aimed at exploring the effect of stereotype threat on the controlled part of memory in older adults using a deep level of processing, namely, self-reference encoding. To meet this objective, 25 younger adults and 25 older adults performed a Remember/Know recognition task following self-reference versus other-reference encoding of adjective traits, under stereotype threat or not. The results indicated that under stereotype threat, older adults' production of Remember responses was specifically impaired following self-reference encoding. Moreover, whereas executive functioning and group identification did not moderate stereotype threat effect, measure of self-worth did. These findings suggest that stereotype threat in older adults may be a self-concept threat and that moderators of stereotype threat found in other groups (i.e., group identification and executive functioning) may not be generalised to this group. Rather, as stereotype threat in aging may represent a threat to the self, self-worth might have a central role, whereby individuals with high self-worth remain self-confident even under stereotype threat and are thus able to down-regulate their negative affects to face such a threat.

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This study was designed to assess, through the self-reference effect in memory, whether affective self-representations were modulated by the retrieval conditions and the severity of social anxiety. Three groups (high socially anxious, low socially anxious and non-anxious) were compared on a self-referential task that involved encoding affective trait adjectives under three conditions: self-reference encoding, encoding with reference to the perception of self by others, and other-reference encoding. Memory for trait adjectives was tested on both a free recall task and a Remember/Know/Guess recognition task. The results revealed that while socially anxious individuals explicitly rated as self-descriptive and recalled more positive than negative trait adjectives like non-anxious participants, this positivity bias was respectively reduced and erased among low and high socially anxious participants when recollecting the same adjectives encoded in reference to the self. These findings are discussed in relation to their contribution to the understanding of the emotional memory biases related to the retrieval of self-knowledge in social anxiety. In particular, they highlight the necessity of using the self-reference effect in memory rather than mere self-endorsement of trait adjectives when assessing the efficacy of cognitive therapies for social anxiety.

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The question of an emotional memory enhancement in aging, and of a positivity bias in particular, has been the subject of numerous empirical studies in the last decade. However, the roots of such positive preference are not yet well established. Partisans of a motivation-based perspective contend with those arguing that positivity is related to a cognitive or neural degradation. The aim of this study was to introduce some elements concerning positivity effect in aging. We compared immediate (i.e., immediate recall) versus delayed (i.e., delayed recall and recognition) emotional memory performance in 38 young adults, 39 old adults, 37 very old adults, and 41 Alzheimer's disease patients. Moreover, we manipulated the encoding instruction: Either participants received no particular processing instruction, or they had to process the material in a semantic way. The results indicated that the positivity bias is most likely to occur in individuals whose cognitive functions are preserved, after long retention delay, and in experimental conditions that do not constrain encoding. We concluded by highlighting that although these findings seem to be better in line with the motivation, rather than the degradation, perspective, they do not fully support either theory. (PsycINFO Database Record

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Motor-skill practice in repetitive or variable orders leads to better within-day acquisition and facilitates retention and transfer, respectively. This practice pattern effect has been robustly found for physical practice, but little is known about its effect after motor imagery (MI) practice. In the present study, we investigated the effect of constant or variable MI practice, and the consolidation following a day-time or a sleep interval. The physical performance was assessed before (pre-test) and after MI training (post-test), as well as after a night or day-time consolidation (retention test). Finally, a transfer test on an unpracticed task was further performed. Results revealed that in all participants, performance increased significantly in the post-test when compared with the pre-test, while only subjects in the variable MI training showed further gains in performance in the retention test following a night of sleep, and exhibited the best transfer of performance to a novel visuomotor sequence. In contrast, subjects in the constant MI training did not show any delayed performance gain following both day and sleep-consolidation. Overall, and for the first time, these findings partially support the practice pattern effect of motor learning with MI, and further highlight a new difference between mental and physical practice, especially on consolidation. To conclude, variable MI practice, rather than constant, seems to be the valuable condition that should be considered in the practical implications of mental training in motor learning and rehabilitation.

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The purpose of the present study was to investigate emotional memory enhancement (EME) in Alzheimer's disease (AD). In particular, we were interested in exploring which memory process (i.e., recollection or familiarity) could be improved by emotional information in the course of the disease. Eighteen AD patients were compared with 15 normal controls on the Remember/Know/Guess paradigm following encoding of emotional and neutral words. AD patients' recollective experience was improved for emotional compared to neutral words to the same extent as that of normal controls, whereas emotion had no effect on participants' memory performance involving familiarity processes. Our results showed that AD patients' memory can be enhanced qualitatively but not quantitatively by an emotional material. Furthermore, we found that AD patients were as able as normal controls to benefit from the emotional content of information to improve the recollection of details.

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In human cognition, self and memory processes strongly interact, as evidenced by the memory advantage for self-referential materials [Self-Reference Effect (SRE) and Self-Reference Recollection Effect (SRRE)]. The current study examined this interaction at the behavioural level and its neural correlates in patients with Alzheimer's disease (AD). Healthy older controls (HC) and AD patients performed trait-adjectives judgements either for self-relevance or for other-relevance (encoding phase). In a first experiment, the encoding and subsequent yes-no recognition phases were administrated in a Magnetic Resonance Imaging (MRI) scanner. Brain activation as measured by functional MRI (fMRI) was examined during self-relevance judgements and anatomical images were used to search for correlation between the memory advantage for self-related items and grey matter density (GMD). In a second experiment, participants described the retrieval experience that had driven their recognition decisions (familiarity vs recollective experience). The behavioural results revealed that the SRE and SRRE were impaired in AD patients compared to HC participants. Furthermore, verbal reports revealed that the retrieval of self-related information was preferentially associated with the retrieval of contextual details, such as source memory in the HC participants, but less so in the AD patients. Our imaging findings revealed that both groups activated the medial prefrontal cortex (MPFC) at encoding during self-relevance judgements. However, the variable and limited memory advantage for self-related information was associated with GMD in the lateral prefrontal cortex in the AD patients, a region supporting high-order processes linking self and memory. These findings suggest that even if AD patients engage MPFC during self-referential judgements, the retrieval of self-related memories is qualitatively and quantitatively impaired in relation with altered high-order processes in the lateral PFC.

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Self-referential processing relies mainly on the medial prefrontal cortex (MPFC) and enhances memory encoding (i.e., Self-Reference Effect, SRE) as it improves the accuracy and richness of remembering in both young and older adults. However, studies on age-related changes in the neural correlates of the SRE on the subjective (i.e., autonoetic consciousness) and the objective (i.e., source memory) qualitative features of episodic memory are lacking. In the present fMRI study, we compared the effects of a self-related (semantic autobiographical memory task) and a non self-related (general semantic memory task) encoding condition on subsequent episodic memory retrieval. We investigated encoding-related activity during each condition in two groups of 19 younger and 16 older adults. Behaviorally, the SRE improved subjective memory performance in both groups but objective memory only in young adults. At the neural level, a direct comparison between self-related and non self-related conditions revealed that SRE mainly activated the cortical midline system, especially the MPFC, in both groups. Additionally, in older adults and regardless of the condition, greater activity was found in a fronto-parietal network. Overall, correlations were noted between source memory performance and activity in the MPFC (irrespective of age) and visual areas (mediated by age). Thus, the present findings expand evidence of the role of the MPFC in self-referential processing in the context of source memory benefit in both young and older adults using incidental encoding via semantic autobiographical memory. However, our finding suggests that its role is less effective in aging.

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Age-related changes in autobiographical memory (AM) recall are characterized by a decline in episodic details, while semantic aspects are spared. This deleterious effect is supposed to be mediated by an inefficient recruitment of executive processes during AM retrieval. To date, contrasting evidence has been reported on the neural underpinning of this decline, and none of the previous studies has directly compared the episodic and semantic aspects of AM in elderly. We asked 20 young and 17 older participants to recall specific and general autobiographical events (i.e., episodic and semantic AM) elicited by personalized cues while recording their brain activity by means of fMRI. At the behavioral level, we confirmed that the richness of episodic AM retrieval is specifically impoverished in aging and that this decline is related to the reduction of executive functions. At the neural level, in both age groups, we showed the recruitment of a large network during episodic AM retrieval encompassing prefrontal, cortical midline and posterior regions, and medial temporal structures, including the hippocampus. This network was very similar, but less extended, during semantic AM retrieval. Nevertheless, a greater activity was evidenced in the dorsal anterior cingulate cortex (dACC) during episodic, compared to semantic AM retrieval in young participants, and a reversed pattern in the elderly. Moreover, activity in dACC during episodic AM retrieval was correlated with inhibition and richness of memories in both groups. Our findings shed light on the direct link between episodic AM retrieval, executive control, and their decline in aging, proposing a possible neuronal signature. They also suggest that increased activity in dACC during semantic AM retrieval in the elderly could be seen as a compensatory mechanism underpinning successful AM performance observed in aging. These results are discussed in the framework of recently proposed models of neural reorganization in aging.

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Autobiographical memory (AM) comprises representation of both specific (episodic) and generic (semantic) personal information. Depression is characterized by a shift from episodic to semantic AM retrieval. According to theoretical models, this process ("overgeneralization"), would be linked to reduced executive resources. Moreover, "overgeneral" memories, accompanied by a negativity bias in depression, lead to a pervasive negative self-representation. As executive functions and AM specificity are also closely intricate among "non-clinical" populations, "overgeneral" memories could result in depressive emotional responses. Consequently, our hypothesis was that the neurocognitive profile of healthy subjects showing a rigid negative self-image would mimic that of patients. Executive functions and self-image were measured and brain activity was recorded, by means of fMRI, during episodic AMs retrieval in young healthy subjects. The results show an inverse correlation, that is, a more rigid and negative self-image produces lower performances in both executive and specific memories. Moreover, higher negative self-image is associated with decreased activity in the left ventro-lateral prefrontal and in the anterior cingulate cortex, repeatedly shown to exhibit altered functioning in depression. Activity in these regions, on the contrary, positively correlates with executive and memory performances, in line with their role in executive functions and AM retrieval. These findings suggest that rigid negative self-image could represent a marker or a vulnerability trait of depression by being linked to reduced executive function efficiency and episodic AM decline. These results are encouraging for psychotherapeutic approaches aimed at cognitive flexibility in depression and other psychiatric disorders.

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Episodic memory deficits are almost always the first cognitive impairment in Alzheimer disease (AD). AD is also characterized by a loss of self-awareness. The aim of this article is to give an interpretation of AD patients' episodic impairments through the study of the relationship between memory and the self. Using the Remember/Know paradigm associated with the self-reference effect and emotional valence, we showed that this relationship may be impaired in AD. On the one hand, this could explain AD patients' difficulty accessing autonoetic consciousness, that is to say mentally bring back events of the past. On the other hand, the difficulty to precisely relieve previous events may be in turn at the root of AD patients' loss of self-awareness, namely anosognosia. Thus, based on the previous studies in the field of self-referential processing and on our findings, we proposed that the combination of an emotion analysis and a cognitive approach of AD patients' episodic memory impairments is an interesting way to better understand the complete functioning of AD patients.

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Two previous studies showed that self-reference encoding had no effect on Alzheimer's disease (AD) patients' recollective experience when it was compared to other-reference encoding, whereas it did have an effect when it was compared to semantic processing, but only for emotional trait adjectives. In the present study, the performance of 22 AD patients was compared with that of 21 normal controls on a task involving recognition of emotional versus neutral adjective traits following self-reference versus other-reference encoding, using the remember/know/guess paradigm. Results showed that although AD patients had a positive explicit view of themselves, their self became salient for negative adjective traits only. We concluded that there might exist two ways of processing self-referential knowledge in human cognition: one explicit and the other more implicit.

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Episodic memory deficits are predominately the first cognitive impairment in Alzheimer disease (AD). Previous studies have demonstrated that these deficits are specifically linked to autonoetic consciousness impairment, whereas noetic consciousness remains preserved in AD. This study focused on the self-reference effect and examined emotional valence, as it has been shown that emotional content can enhance memory in AD. A task involving recognition of emotional versus neutral adjective traits after self-reference versus semantic encoding, and using the Remember/Know/Guess paradigm was administered to 22 AD patients and 18 normal controls. Results for AD patients show that self-reference increased autonoetic consciousness only for emotional and particularly negative trait adjectives. This interesting result indicates that neutral valence does not allow properties of the self to emerge in AD patients because of the progressive loss of the sense of self-linked to the disease, whereas emotional valence does.

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Neuropsychological and neuroimaging data suggest that the self-memory system can be fractionated into three functionally independent systems processing personal information at several levels of abstraction, including episodic memories of one's life (episodic autobiographical memory, EAM), semantic knowledge of facts about one's life (semantic autobiographical memory, SAM), and semantic knowledge of one's personality [conceptual self, (CS)]. Through the study of two developmental amnesic patients suffering of neonatal brain injuries, we explored how the different facets of the self-memory system develop when growing up with bilateral hippocampal atrophy. Neuropsychological evaluations showed that both of them suffered from dramatic episodic learning disability with no sense of recollection (Remember/Know procedure), whereas their semantic abilities differed, being completely preserved (Valentine) or not (Jocelyn). Magnetic resonance imaging, including quantitative volumetric measurements of the hippocampus and adjacent (entorhinal, perirhinal, and temporopolar) cortex, showed severe bilateral atrophy of the hippocampus in both patients, with additional atrophy of adjacent cortex in Jocelyn. Exploration of EAM and SAM according to lifetime periods covering the entire lifespan (TEMPAu task, Piolino et al., 2009) showed that both patients had marked impairments in EAM, as they lacked specificity, details and sense of recollection, whereas SAM was completely normal in Valentine, but impaired in Jocelyn. Finally, measures of patients' CS (Tennessee Self-Concept Scale, Fitts and Warren, 1996), checked by their mothers, were generally within normal range, but both patients showed a more positive self-concept than healthy controls. These two new cases support a modular account of the medial-temporal lobe with episodic memory and recollection depending on the hippocampus, and semantic memory and familiarity on adjacent cortices. Furthermore, they highlight developmental episodic and semantic functional independence within the self-memory system suggesting that SAM and CS may be acquired without episodic memories.

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