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. 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

Local Processing Bias Impacts Implicit and Explicit Memory in Autism

Autism spectrum disorder (ASD) is characterized by atypical perception, including processing that is biased toward local details rather than global configurations. This bias may impact on memory. The present study examined the effect of this perception on both implicit (Experiment 1) and explicit (Experiment 2) memory in conditions that promote either local or global processing. The first experiment consisted of an object identification priming task using two distinct encoding conditions: one favoring local processing (Local condition) and the other favoring global processing (Global condition) of drawings. The second experiment focused on episodic (explicit) memory with two different cartoon recognition tasks that favored either local (i.e., processing specific details) or a global processing (i.e., processing each cartoon as a whole). In addition, all the participants underwent a general clinical cognitive assessment aimed at documenting their cognitive profile and enabling correlational analyses with experimental memory tasks. Seventeen participants with ASD and 17 typically developing (TD) controls aged from 10 to 16 years participated to the first experiment and 13 ASD matched with 13 TD participants were included for the second experiment. Experiment 1 confirmed the preservation of priming effects in ASD but, unlike the Comparison group, the ASD group did not increase his performance as controls after a globally oriented processing. Experiment 2 revealed that local processing led to difficulties in discriminating lures from targets in a recognition task when both lures and targets shared common details. The correlation analysis revealed that these difficulties were associated with processing speed and inhibition. These preliminary results suggest that natural perceptual processes oriented toward local information in ASD may impact upon their implicit memory by preventing globally oriented processing in time-limited conditions and induce confusion between explicit memories that share common details

[A cross-sectional study of trait-anxiety in a group of 111 intellectually gifted children].

International audienceINTRODUCTION: Intellectually gifted children are often thought to display a high risk for psychopathology. However, this assertion has received only few direct arguments to date, and there is in fact a lack of knowledge on this subject. The aim of this study was to compare trait-anxiety - which is considered as a sensitive and early indicator of psychoaffective difficulties in children - in intellectually gifted children to the norm. METHODS: One hundred and eleven children aged 8 to 12 and with an intellectual quotient (IQ) higher than 129 participated in the study. They were recruited in a hospital department of child and adolescent psychiatry and through psychologists' private practice, where they attended consultation because of academic underachievement and/or social maladjustment. All the children were examined by trained psychiatrists and psychologists: none had a present or past medical or psychiatric condition and, additionally, none had an elevated score on the French version of the Children's Depressive Rating Scale Revised (Moor & Mack, 1982). Parents filled in a questionnaire for the collection of socio-demographic data and children answered the French version of the Revised-Children's Manifest Anxiety Scale (R-CMAS; Reynolds, 1999), a 37-items self-assessment of trait-anxiety, the psychometric properties of which have been validated in children with high IQ. DATA ANALYSIS: Mean scores and subscores on the R-CMAS in the whole studied group and as a function of gender and age were compared to French normative data (Reynolds, 1999) by calculation of 95% confidence intervals; subgroups were compared using Student's t-tests. Proportions of children who's score and subscores exceeded anxiety cut-off norms were compared to normative data using chi-square tests. Statistical significance was considered at the P<0.05 level. RESULTS: The studied group comprised mainly boys, and members of a sibling. Parents mainly lived as man and wife, had high academic levels, and had a professional activity. The confidence intervals of the R-CMAS scores and subscores all comprised their normative value, which denotes that no difference was statistically significant. Comparisons for age and gender showed no significant difference. Proportions of results exceeding the cut-off scores and subscores did not significantly differ from the norms. DISCUSSION: General and dimensional trait-anxiety levels in the studied group were comparable to normative data. These results are in accordance with previous studies of trait-anxiety in children and adolescents with high IQ, which all showed normal or decreased levels. These findings do not corroborate the hypothesis that intellectual giftedness constitutes a risk factor for psychopathology. LIMITS: The studied group was a clinical one, which could limit the generalisation of the results. However, mental disorders were ruled out, and the psychometric and socio-demographic characteristics of the group were in keeping with those described for the general population of gifted children. Moreover, considering that participant children displayed academic underachievement and/or social maladjustment, it can be supposed that their anxiety levels were not lower than those in the general population of gifted children. Secondly, the potentially confusing effect of socio-demographic variables (underrepresentation of low socio-economic levels and single-parent families) could not be statistically taken into account, due to the absence of a specific control group. CONCLUSION: Intellectually gifted children seem not to display increased trait-anxiety. However, further studies are necessary to investigate psychological functioning in gifted children and their risk for psychopathology

Self-representation in Kleine-Levin syndrome: a single case fMRI study

International audienceKleine-Levin syndrome (KLS) is characterized by recurrent episodes of hypersomnia, compulsive hyperphagia, disinhibition, hypersexuality and self modifications. To investigate the Self, we used afunctional magnetic resonance imaging paradigm evaluating Self-reference processing (SRP) and Self-reference effect (SRE) in a17-year-old male adolescent at the end of an episode. We observed enhanced activations in right hemisphere and posterior areas- associated with physical Self representations- during the SRP condition, while during the SRE condition, enhanced activations in bilateral but prevailing left frontal areas- associated with the conceptual Self. These results suggest amodified Self during aKLS episode being more physically grounded

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

How scene encoding affects memory discrimination: Analysing eye movements data using data driven methods

Encoding of visual scenes remains under-explored due to methodological limitations. In this study, we evaluated the relationship between memory accuracy for visual scenes and eye movements at encoding. First, we used data-driven methods, a fixation density map (using iMap4) and a saliency map (using GBVS), to analyse the visual attention for items. Second, and in a more novel way, we conducted scanpath analyses without a priori (using ScanMatch). Scene memory accuracy was assessed by asking participants to discriminate identical scenes (targets) among rearranged scenes sharing some items with targets (distractors) and new scenes. Shorter fixation duration in regions of interest (ROIs) at encoding was associated with a better rejection of distractors; there was no significant difference in the relative fixation time in ROIs at encoding, between subsequent hits and misses at test. Hence, density of eye fixations in data-driven ROIs seems to be a marker of subsequent memory discrimination and pattern separation. Interestingly, we also identified a negative correlation between average MultiDimensional Scaling (MDS) distance scanpaths and the correct rejection of distractors, indicating that scanpath consistency significantly affects the ability to discriminate distractors from targets. These data suggest that visual exploration at encoding participates in discrimination processes at test