Intact memory storage but impaired retrieval in visual memory in autism: New insights from an electrophysiological study.

In a recent study on visual episodic memory (Desaunay, Clochon, et al., 2020), we have shown event-related potentials (ERPs) differences associated with priming (150-300 msec), familiarity (350-470 msec), and recollection (600-700 msec), in young people with autism spectrum disorders (ASD) compared with typical development (TD). To go further into the study of the processes of storage and retrieval of the memory trace, we re-analyzed Desaunay, Clochon, et al's data using time-frequency analysis, that is, event-related synchronization and desynchronization (ERS/ERD). This allows a decomposition of the spectral power within frequency bands associated with these ERPs. We focused both on the same time windows and the same regions of interest as previously published. We mainly identified, in ASD compared with TD, reduced ERS in low-frequencies (delta, theta) in early time-windows, and non-significant differences in ERD in higher frequencies (alpha, beta1) in all time-windows. Reduced ERS during recognition confirmed previously reported diminution of priming effects and difficulties in manipulation and retrieval of both semantic and episodic information. Conversely, preserved ERD corroborates a preservation of memory storage processes. These observations are consistent with a cognitive model of memory in ASD, that suggests difficulties in cognitive operations or executive demand at retrieval, subsequent to successful long-term storage of information. LAY SUMMARY: We assessed the EEG synchronization and desynchronization, during visual episodic recognition. We observed, in youth with Autism, reduced synchronization in low-frequencies (delta, theta), suggesting reduced access to and manipulation of long-term stored information. By contrast, non-significant differences in desynchronization at higher frequencies (alpha, beta frequency bands), that support long-term stored semantic and episodic information, suggested preserved memory traces.

EEG resting-state functional connectivity: evidence for an imbalance of external/internal information integration in autism.

BACKGROUND: Autism spectrum disorder (ASD) is associated with atypical neural activity in resting state. Most of the studies have focused on abnormalities in alpha frequency as a marker of ASD dysfunctions. However, few have explored alpha synchronization within a specific interest in resting-state networks, namely the default mode network (DMN), the sensorimotor network (SMN), and the dorsal attention network (DAN). These functional connectivity analyses provide relevant insight into the neurophysiological correlates of multimodal integration in ASD. METHODS: Using high temporal resolution EEG, the present study investigates the functional connectivity in the alpha band within and between the DMN, SMN, and the DAN. We examined eyes-closed EEG alpha lagged phase synchronization, using standardized low-resolution brain electromagnetic tomography (sLORETA) in 29 participants with ASD and 38 developing (TD) controls (age, sex, and IQ matched). RESULTS: We observed reduced functional connectivity in the ASD group relative to TD controls, within and between the DMN, the SMN, and the DAN. We identified three hubs of dysconnectivity in ASD: the posterior cingulate cortex, the precuneus, and the medial frontal gyrus. These three regions also presented decreased current source density in the alpha band. CONCLUSION: These results shed light on possible multimodal integration impairments affecting the communication between bottom-up and top-down information. The observed hypoconnectivity between the DMN, SMN, and DAN could also be related to difficulties in switching between externally oriented attention and internally oriented thoughts.

Autobiographical Memory and Social Identity in Autism: Preliminary Results of Social Positioning and Cognitive Intervention.

Autobiographical memory (AM) is closely linked to the self-concept, and fulfills directive, identity, social, and adaptive functions. Individuals with autism spectrum disorder (ASD) are now known to have atypical AM, which may be closely associated with social communication difficulties. This may result in qualitatively different autobiographical narratives, notably regarding social identity. In the present study, we sought to investigate this concept and develop a cognitive intervention targeting individuals with ASD. First, 13 adolescents with ASD and 13 typically developing adolescents underwent an AM interview featuring an original coding system designed to analyze the social self. We observed that the narratives produced by the ASD group focused more on the family than on extended social spheres, compared with those of the comparison group. Moreover, participants with ASD did not include themselves in the social groups they mentioned, and produced more references to others, compared with typically developing participants. Second, we designed a cognitive intervention program consisting of individual and group sessions that targeted AM. We conducted a pilot study among three adolescents with ASD aged 12, 16, and 17 years. Preliminary results showed that the program increased extra-family narrative references by the two youngest adolescents, who produced more social integration markers. Our study of autobiographical narratives yielded interesting findings about social positioning in ASD and showed how AM can be targeted in rehabilitation programs as a vector of social interaction.

Exploring the Event-Related Potentials' Time Course of Associative Recognition in Autism.

Behavioral data on episodic recollection in autism spectrum disorders (ASD) point limited relational memory functioning. However, the involvement of successive memory processes in the profile of episodic memory in ASD needs more study. Here, we used event-related potentials (ERP) to investigate the time course of episodic recollection with an associative recognition paradigm with picture pairs. Twenty-two participants with ASD and 32 with typical development (TD), all right-handed, were included. Behavioral results confirmed difficulties in correctly recognizing identical pairs in the ASD relative to TD group. We found an unexpected amplitude decrement on the P2 (220-270 msec) and FN400 (350-470 msec) potentials, suggesting diminished priming and familiarity effects in the ASD relative to TD group. However, ERP data revealed that the recognition of associative information relies on the same electrophysiological process (old/new effect in the 600-700-msec late positive component) in ASD participants as in TD ones, with a parietal extension in the ASD group. These results suggest that the electrophysiological processes of associative recognition are qualitatively similar in individuals with and without ASD but may differ quantitatively. This difference may be driven by the reduced early processing of picture pairs that may in turn lead to their diminished integration into the semantic memory system, being partially compensated by a greater involvement of associative memory during the recollection process. Other studies would be useful to go further in identifying these cognitive processes involved in atypical recognition in ASD and their neural substrates. Autism Res 2020, 13: 1998-2016. © 2020 International Society for Autism Research and Wiley Periodicals LLC LAY SUMMARY: We identified diminished performance on the associative recognition of picture pairs in adolescents and young adults with autism when compared to typical development. Electrophysiological data revealed qualitative similarities but quantitative differences between-group, with diminished priming and familiarity processes partially compensated by an enhanced parietal recollection process.

Positive Effect of Visual Cuing in Episodic Memory and Episodic Future Thinking in Adolescents With Autism Spectrum Disorder.

Cognitive studies generally report impaired autobiographical memory in individuals with autism spectrum disorder (ASD), but mostly using verbal paradigms. In the present study, we therefore investigated the properties of both past and future autobiographical productions using visual cues in 16 boys with ASD and 16 typically developing (TD) participants aged between 10 and 18 years. We focused on sensory properties, emotional properties, and recollection, probing past and future productions for both near and distant time periods. Results showed that the ASD group performed more poorly than controls on free recall for recent periods, but performed like them when provided with visual cues. In addition, the ASD group reported fewer sensory details than controls and exhibited difficulties in the experience of recollection for the most remote events. These data suggest a combination of consolidation and binding deficits. Finally, our findings reveal the relevance of using visual cues to probe autobiographical memory, with possible perspectives for memory rehabilitation.

The distinctive role of executive functions in implicit emotion regulation.

Several theoretical models stress the role of executive functions in emotion regulation (ER). However, most of the previous studies on ER employed explicit regulatory strategies that could have engaged executive functions, beyond regulatory processes per se. Recently, there has been renewed interest in implicit forms of ER, believed to be closer to daily-life requirements. While various studies have shown that implicit and explicit ER engage partially overlapping neurocognitive processes, the contribution of different executive functions in implicit ER has not been investigated. In the present study, we presented participants with negatively valenced pictures of varying emotional intensity preceded by short texts describing them as either fictional or real. This manipulation was meant to induce a spontaneous emotional down-regulation. We recorded electrodermal activity (EDA) and subjective reports of emotion arousal. Executive functions (updating, switching, and inhibition) were also assessed. No difference was found between the fictional and real condition on EDA. A diminished self-reported arousal was observed, however, when pictures were described as fictional for high- and mild-intensity material, but not for neutral material. The amount of down-regulation in the fictional condition was found to be predicted by interindividual variability in updating performances, but not by the other measures of executive functions, suggesting its implication even in implicit forms of ER. The relationship between down-regulation and updating was significant only for high-intensity material. We discuss the role of updating in relation to the consciousness of one's emotional state.

The paradox of fiction: Emotional response toward fiction and the modulatory role of self-relevance.

For over forty years, philosophers have struggled with the "paradox of fiction", which is the issue of how we can get emotionally involved with fictional characters and events. The few neuroscientific studies investigating the distinction between the processing of real and fictional entities have evidenced that midline cortical structures and lateral fronto-parietal regions are more engaged for real and fictional entities, respectively. Interestingly, the former network is engaged in autobiographical memory retrieval and self-reference, processes that are known to boost emotional reactivity, while the latter underpins emotion regulation. Thus, a possible modulation of the emotional response according to the nature (real or fictional) of the stimulus is conceivable. To test this hypothesis, we presented short emotional (negative and positive) and neutral video as fictional or real. For negative material, we found that subjective emotional experience, but not physiological arousal measured by electrodermal activity, was reduced in the fictional condition. Moreover, the amount of personal memories linked to the scenes counteracted this effect boosting the subjective emotional response. On the contrary, personal memories elicited by the scenes, but not fiction, modulate the emotional response for positive material. These results suggest that when a stimulus triggers a personal memory, the emotional response is less prone to be modulated by contextual factors, and suggest that personal engagement could be responsible for emotional reaction toward fiction. We discuss these results in the emotion regulation framework and underline their implications in informing theoretical accounts of emotion in the neuroscientific domain and the philosophical debate on the paradox of emotional response to fiction.