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Small average differences in the left-right asymmetry of cerebral cortical thickness have been reported in individuals with autism spectrum disorder (ASD) compared to typically developing controls, affecting widespread cortical regions. The possible impacts of these regional alterations in terms of structural network effects have not previously been characterized. Inter-regional morphological covariance analysis can capture network connectivity between different cortical areas at the macroscale level. Here, we used cortical thickness data from 1455 individuals with ASD and 1560 controls, across 43 independent datasets of the ENIGMA consortium's ASD Working Group, to assess hemispheric asymmetries of intra-individual structural covariance networks, using graph theory-based topological metrics. Compared with typical features of small-world architecture in controls, the ASD sample showed significantly altered average asymmetry of networks involving the fusiform, rostral middle frontal, and medial orbitofrontal cortex, involving higher randomization of the corresponding right-hemispheric networks in ASD. A network involving the superior frontal cortex showed decreased right-hemisphere randomization. Based on comparisons with meta-analyzed functional neuroimaging data, the altered connectivity asymmetry particularly affected networks that subserve executive functions, language-related and sensorimotor processes. These findings provide a network-level characterization of altered left-right brain asymmetry in ASD, based on a large combined sample. Altered asymmetrical brain development in ASD may be partly propagated among spatially distant regions through structural connectivity.
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Trastorno del Espectro Autista , Encéfalo , Mapeo Encefálico , Corteza Cerebral/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Vías NerviosasRESUMEN
Maternal gestational obesity is a risk factor for offspring's neurodevelopment and later neuro-cognitive disorders. Altered gut microbiota composition has been found in patients with neurocognitive disorders, and in relation to maternal metabolic health. We explored the associations between gut microbiota and cognitive development during infancy, and their link with maternal obesity. In groups of children from the Pisa birth Cohort (PISAC), we analysed faecal microbiota composition by 16S rRNA marker gene sequencing of first-pass meconium samples and of faecal samples collected at age 3, 6, 12, 24, 36 months, and its relationship with maternal gestational obesity or diabetes, and with cognitive development, as measured from 6 to 60 months of age by the Griffith's Mental Development Scales. Gut microbiota composition in the first phases of life is dominated by Bifidobacteria (Actinobacteria phylum), with contribution of Escherichia/Shigella and Klebsiella genera (Proteobacteria phylum), whereas Firmicutes become more dominant at 36 months of age. Maternal overweight leads to lower abundance of Bifidobacterium, Blautia and Ruminococcus, and lower practical reasoning scores in the offspring at the age of 36 months. In the whole population, microbiota in the first-pass meconium samples shows much higher alpha diversity compared to later samples, and its composition, particularly Bifidobacterium and Veillonella abundances, correlates with practical reasoning scores at 60 months of age. Maternal overweight correlates with bacterial colonization and with the development of reasoning skills at pre-school age. Associations between neonatal gut colonization and later cognitive function provide new perspectives of primary (antenatal) prevention of neurodevelopmental disorders.
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Microbioma Gastrointestinal , Microbiota , Niño , Preescolar , Cognición , Femenino , Microbioma Gastrointestinal/genética , Humanos , Recién Nacido , Sobrepeso , Embarazo , ARN Ribosómico 16S/genéticaRESUMEN
BACKGROUND: Joint actions, described as a form of social interaction in which individuals coordinate their actions in space and time to bring about a change in the environment, rely on sensory-motor processes that play a role in the development of social skills. Two brain networks, associated with "mirroring" and "mentalizing", are engaged during these actions: the mirror neuron and the theory of mind systems. People with autism spectrum disorder (ASD) showed impairment in interpersonal coordination during joint actions. Studying joint action coordination in ASD will contribute to clarify the interplay between sensory-motor and social processes throughout development and the interactions between the brain and the behavior. METHOD: This review focused on empirical studies that reported behavioral and kinematic findings related to joint action coordination in people with ASD. RESULTS: Literature on mechanisms involved in the joint action coordination impairment in ASD is still limited. Data are controversial. Different key-components of joint action coordination may be impaired, such as cooperative behavior, temporal coordination, and motor planning. CONCLUSIONS: Interpersonal coordination during joint actions relies on early sensory-motor processes that have a key role in guiding social development. Early intervention targeting the sensory-motor processes involved in the development of joint action coordination could positively support social skills.
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Trastorno del Espectro Autista , Neuronas Espejo , Encéfalo , Conducta Cooperativa , Humanos , IntenciónRESUMEN
This paper aims to propose that the psychiatrist George Frankl had more than a marginal role in the early history of autism. Frankl's conception of autism as characterized by a lack of affective language has influenced both Asperger and Kanner. First, this proposal is historically supported; second it is corroborated by Frankl's unpublished manuscript on Autism. We found that Frankl's perspective about autism was, and still can be, considered innovative for multiple reasons. Specifically, Frankl proposed that autism could cover a spectrum of conditions; that it is a state of mind that is not necessarily abnormal; and that it is a neurobiological condition, which primarily needs to be understood by others. Finally, Frankl's concepts of affective contact and affective language are reconsidered with reference to contemporary neuropsychology from which autism emerges not as a higher-order cognitive deficit, but as a result of an impairment of primordial ability to process low level sensory, motor and perceptual information gained through experiencing other persons.
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Trastorno Autístico , Psiquiatría , Humanos , LenguajeRESUMEN
Autism-spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD) are early neurodevelopmental conditions that share clinical characteristics, raising important issues in clinical diagnosis. We aimed to compare (1) sensory processing in four groups of children: ASD alone, ASD + ADHD, ADHD alone, and typical development (TD) and (2) the association between sensory processing and attention in the three groups with neurodevelopmental disorders. Our sample included 120 children aged from 6 to 12 years divided into four groups: ASD alone (N = 43), ASD + ADHD (N = 18), ADHD alone (N = 28), and TD (N = 31). Atypical sensory processing was more frequent in ASD and/or ADHD than in TD, without a significant difference between ASD and ADHD. However, the variance analysis of attention problems revealed differences between the ADHD and ASD groups. Thus, the rate of atypical sensory processing was comparable between the ASD and ADHD groups, suggesting that further studies are needed to explore atypical SP in all neurodevelopmental disorders.
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Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno del Espectro Autista/diagnóstico , Percepción/fisiología , Atención , Niño , Femenino , Humanos , MasculinoRESUMEN
OBJECTIVE: Increasing literature reported higher rates of psychiatric disorders in parents of children with autism spectrum disorder (ASD), as well as of autistic-like features in social and cognitive functioning. However, little attention has been paid to the association between autistic traits (AT) and global functioning in this population. The aim of the present work was to investigate clinical and functional correlates of AT among parents of ASD children, with a specific focus on ruminative thinking. METHODS: One hundred and twenty parents of ASD children were assessed by the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (DSM-5), the Adult Autism Subthreshold Spectrum (AdAS Spectrum), the Ruminative Response Scale (RRS), the Social and Occupational Functioning Assessment Scale (SOFAS). RESULTS: Subjects with at least 1 psychiatric disorder (39.2%) showed significantly higher AdAS Spectrum and RRS scores. Subjects with a history of school difficulties and with language development alterations scored significantly higher on specific AdAS Spectrum domains. A significant negative correlation was found between SOFAS and AdAS Spectrum scores, as well as between SOFAS and RRS scores. AdAS Spectrum nonverbal communication domain score was identified has a statistically predictive variable for the presence of psychiatric disorders and lower SOFAS scores. Finally, we found a significant indirect effect of AdAS total score on SOFAS score, which was fully mediated by RRS total score. CONCLUSIONS: AT in parents of ASD children seem to be associated with a higher vulnerability toward psychopathology and with a lower global functioning. Ruminative thinking may play a role in the relationship between AT and functional outcome.
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Trastorno del Espectro Autista/psicología , Padres/psicología , Rumiación Cognitiva , Adulto , Trastorno del Espectro Autista/diagnóstico , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , FenotipoRESUMEN
The intermethod agreement between automated algorithms for brainstem segmentation is investigated, focusing on the potential involvement of this structure in Autism Spectrum Disorders (ASD). Inconsistencies highlighted in previous studies on brainstem in the population with ASD may in part be a result of poor agreement in the extraction of structural features between different methods. A sample of 76 children with ASD and 76 age-, gender-, and intelligence-matched controls was considered. Volumetric analyses were performed using common tools for brain structures segmentation, namely FSL-FIRST, FreeSurfer (FS), and Advanced Normalization Tools (ANTs). For shape analysis SPHARM-MAT was employed. Intermethod agreement was quantified in terms of Pearson correlations between pairs of volumes obtained by the different methods. The degree of overlap between segmented masks was quantified in terms of the Dice index. Both Pearson correlations and Dice indices, showed poor agreement between FSL-FIRST and the other methods (ANTs and FS), which by contrast, yielded Pearson correlations greater than 0.93 and average Dice indices greater than 0.76 when compared with each other. As with volume, shape analyses exhibited discrepancies between segmentation methods, with particular differences noted between FSL-FIRST and the others (ANT and FS), with under- and over-segmentation in specific brainstem regions. These data suggest that research on brain structure alterations should cross-validate findings across multiple methods. We consistently detected an enlargement of brainstem volume in the whole sample and in the male cohort across multiple segmentation methods, a feature particularly driven by the subgroup of children with idiopathic intellectual disability associated with ASD.
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Trastorno del Espectro Autista/patología , Tronco Encefálico/patología , Neuroimagen/métodos , Trastorno del Espectro Autista/diagnóstico por imagen , Tronco Encefálico/diagnóstico por imagen , Niño , Preescolar , Femenino , Humanos , Imagen por Resonancia Magnética , MasculinoRESUMEN
Bayesian accounts of autism suggest that this disorder may be rooted in an impaired ability to estimate the probability of future events, possibly owing to reduced priors. Here, we tested this hypothesis within the action domain in children with and without autism using a behavioural paradigm comprising a familiarization and a testing phase. During familiarization, children observed videos depicting a child model performing actions in diverse contexts. Crucially, within this phase, we implicitly biased action-context associations in terms of their probability of co-occurrence. During testing, children observed the same videos but drastically shortened (i.e. reduced amount of kinematics information) and were asked to infer action unfolding. Since during the testing phase movement kinematics became ambiguous, we expected children's responses to be biased to contextual priors, thus compensating for perceptual uncertainty. While this probabilistic effect was present in controls, no such modulation was observed in autistic children, overall suggesting an impairment in using contextual priors when predicting other peoples' actions in uncertain environments.
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Trastorno Autístico/psicología , Movimiento , Desempeño Psicomotor , Fenómenos Biomecánicos , Niño , Femenino , Humanos , Italia , Masculino , ProbabilidadRESUMEN
BACKGROUND: Gastrointestinal (GI) problems are one of the most frequent comorbidities in Autism Spectrum Disorder (ASD) but can be under-recognized due to the concomitant communication difficulties of this population. Accordingly, some associated behaviors (AB) such as verbal and motor behaviors (VB and MB, respectively) have been identified as a possible expression of an underlying GI problem and evaluated through an ad hoc questionnaire (the Associated Behaviors Questionnaire -ABQ-). The aims of this study were to investigate the presence and the type of AB in an Italian sample of ASD preschoolers, and to determine their correlations with GI problems. METHODS: We included 85 ASD preschoolers (mean age 4.14 years; SD 1.08) splitted into two groups (GI and No-GI) through the GI Severity Index instrument. AB were evaluated through the ABQ that includes VB, MB and Changes in overall state (C) clusters. Specific tools were administered to evaluate the ASD core ad associated symptoms, as well as the intellective and adaptive functioning. RESULTS: The GI group (N = 30) showed significantly higher scores in all the three ABQ areas (VB, MB and C) than the No-GI group (N = 55), with a positive correlation between GI symptoms and some specific AB as well as ABQ Total score. By dividing the whole sample in verbal and non-verbal individuals, both specific and shared AB emerged in the two groups. CONCLUSIONS: Our results alert clinicians to consider behavioral manifestations as a possible expression of GI problems in ASD subjects. Therefore, the evaluation of AB may be useful to identify the presence of GI problems in the ASD populations, and especially in non-verbal ASD children.
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Trastorno del Espectro Autista/complicaciones , Enfermedades Gastrointestinales/diagnóstico , Actividad Motora , Conducta Verbal , Dolor Abdominal/complicaciones , Dolor Abdominal/diagnóstico , Análisis de Varianza , Preescolar , Femenino , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/diagnóstico , Enfermedades Gastrointestinales/complicaciones , Humanos , Masculino , Índice de Severidad de la Enfermedad , Encuestas y CuestionariosRESUMEN
A growing body of literature has identified volume alterations of the corpus callosum (CC) in subjects with autism spectrum disorders (ASD). However, to date very few investigations have been conducted on pre-school-age ASD children. This study aims to compare the volume of CC and its sub-regions between pre-schoolers with ASD and controls (CON) and to examine their relationship to demographic and clinical variables (sex, age, non-verbal IQ -NVIQ-, expressive non-echolalic language, emotional and behavioural problems, and autism severity). The volume of CC of 40 pre-schoolers with ASD (20 males and 20 females; mean age: 49 ± 12 months; mean NVIQ: 73 ± 22) and 40 sex-, age-, and NVIQ-matched CON subjects (20 M and 20 F; mean age: 49 ± 14 months; mean NVIQ: 73 ± 23) were quantified applying the FreeSurfer automated parcellation software on Magnetic Resonance images. No significant volumetric differences in CC total volume and in its sub-regions between ASD and CON were found using total brain volume as a covariate. Analogously, absence of CC volumetric differences was evident when boys and girls with ASD were compared with their matched controls. The CC total volume of younger ASD male subjects was found significantly larger with respect to matched CON, which is consistent with the atypical growth trajectory widely reported in these young children. The CC total volume was negatively correlated with autism severity, whereas no association between CC volume and other clinical variables was detected. If replicated, the indirect relationship between CC volume and autism severity suggests the involvement of CC in core ASD symptoms.
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Trastorno del Espectro Autista/patología , Trastorno del Espectro Autista/fisiopatología , Cuerpo Calloso/patología , Factores de Edad , Trastorno del Espectro Autista/diagnóstico por imagen , Estudios de Casos y Controles , Preescolar , Cuerpo Calloso/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Caracteres SexualesRESUMEN
Autism is known to be associated with major perceptual atypicalities. We have recently proposed a general model to account for these atypicalities in Bayesian terms, suggesting that autistic individuals underuse predictive information or priors. We tested this idea by measuring adaptation to numerosity stimuli in children diagnosed with autism spectrum disorder (ASD). After exposure to large numbers of items, stimuli with fewer items appear to be less numerous (and vice versa). We found that children with ASD adapted much less to numerosity than typically developing children, although their precision for numerosity discrimination was similar to that of the typical group. This result reinforces recent findings showing reduced adaptation to facial identity in ASD and goes on to show that reduced adaptation is not unique to faces (social stimuli with special significance in autism), but occurs more generally, for both parietal and temporal functions, probably reflecting inefficiencies in the adaptive interpretation of sensory signals. These results provide strong support for the Bayesian theories of autism.
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Adaptación Psicológica , Trastornos Generalizados del Desarrollo Infantil/fisiopatología , Niño , Femenino , Humanos , MasculinoRESUMEN
BACKGROUND: This study addresses the need for a theoretical base to develop more effective early autism spectrum disorders (ASD) detection tools. The structure that underlies early ASD detection is explored by evaluating the opinions of experts on ASD screening tools currently used in Europe. METHOD: A process of face and content validity was performed. First, the best constructs were selected from the relevant tests: Checklist for Early Signs of Developmental Disorders (CESDD), Checklist for Autism in Toddlers (CHAT), Early Screening of Autistic Traits Questionnaire (ESAT), Modified Checklist for Autism in Toddlers (M-CHAT), Social Communication Questionnaire (SCQ) and Communication and Symbolic Behaviour Scales Developmental Profile (CSBS-DP). The diagnostic content validity model by Fehring (1986, 1994) was adapted to make the selection. Afterwards, the items, taken from these tests, were selected to fit into each construct, using the same methodology. RESULTS: Twelve of the 18 constructs were selected by the experts and 11 items were chosen from a total of 130, reduced to eight after eliminating tautologies. CONCLUSIONS: Mapping these constructs and items on to the DSM-5 diagnostic criteria for ASD indicated good face and content validity. Results of this research will contribute to efforts to improve early ASD screening instruments and identify the key behaviours that experts in ASD see as the most relevant for early detection.
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Importance: Music therapy may facilitate skills in areas affected by autism spectrum disorder (ASD), such as social interaction and communication. Objective: To evaluate effects of improvisational music therapy on generalized social communication skills of children with ASD. Design, Setting, and Participants: Assessor-blinded, randomized clinical trial, conducted in 9 countries and enrolling children aged 4 to 7 years with ASD. Children were recruited from November 2011 to November 2015, with follow-up between January 2012 and November 2016. Interventions: Enhanced standard care (n = 182) vs enhanced standard care plus improvisational music therapy (n = 182), allocated in a 1:1 ratio. Enhanced standard care consisted of usual care as locally available plus parent counseling to discuss parents' concerns and provide information about ASD. In improvisational music therapy, trained music therapists sang or played music with each child, attuned and adapted to the child's focus of attention, to help children develop affect sharing and joint attention. Main Outcomes and Measures: The primary outcome was symptom severity over 5 months, based on the Autism Diagnostic Observation Schedule (ADOS), social affect domain (range, 0-27; higher scores indicate greater severity; minimal clinically important difference, 1). Prespecified secondary outcomes included parent-rated social responsiveness. All outcomes were also assessed at 2 and 12 months. Results: Among 364 participants randomized (mean age, 5.4 years; 83% boys), 314 (86%) completed the primary end point and 290 (80%) completed the last end point. Over 5 months, participants assigned to music therapy received a median of 19 music therapy, 3 parent counseling, and 36 other therapy sessions, compared with 3 parent counseling and 45 other therapy sessions for those assigned to enhanced standard care. From baseline to 5 months, mean ADOS social affect scores estimated by linear mixed-effects models decreased from 14.08 to 13.23 in the music therapy group and from 13.49 to 12.58 in the standard care group (mean difference, 0.06 [95% CI, -0.70 to 0.81]; P = .88), with no significant difference in improvement. Of 20 exploratory secondary outcomes, 17 showed no significant difference. Conclusions and Relevance: Among children with autism spectrum disorder, improvisational music therapy, compared with enhanced standard care, resulted in no significant difference in symptom severity based on the ADOS social affect domain over 5 months. These findings do not support the use of improvisational music therapy for symptom reduction in children with autism spectrum disorder. Trial Registration: isrctn.org Identifier: ISRCTN78923965.
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Trastorno del Espectro Autista/terapia , Musicoterapia , Habilidades Sociales , Atención , Trastorno del Espectro Autista/psicología , Niño , Preescolar , Femenino , Humanos , Masculino , Método Simple Ciego , Resultado del TratamientoRESUMEN
BACKGROUND: Autism is a multifactorial condition in which a single risk factor can unlikely provide comprehensive explanation for the disease origin. Moreover, due to the complexity of risk factors interplay, traditional statistics is often unable to explain the core of the problem due to the strong inherent nonlinearity of relationships. The aim of this study was to assess the frequency of 27 potential risk factors related to pregnancy and peri-postnatal period. METHODS: The mothers of 45 autistic children and of 68 typical developing children completed a careful interview. Twenty-four siblings of 19 autistic children formed an internal control group. RESULTS: A higher prevalence of potential risk factors was observed in 22 and 15 factors in external control and internal control groups, respectively. For six of them, the difference in prevalence was statistically significant. Specialized artificial neural networks (ANNs) discriminated between autism and control subjects with 80.19% global accuracy when the dataset was preprocessed with TWIST (training with input selection and testing) system selecting 16 out of 27 variables. Logistic regression applied to 27 variables gave unsatisfactory results with global accuracy of 46%. CONCLUSION: Pregnancy factors play an important role in autism development. ANNs are able to build up a predictive model, which could represent the basis for a diagnostic screening tool.
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Trastorno Autístico/epidemiología , Redes Neurales de la Computación , Complicaciones del Embarazo/epidemiología , Adolescente , Adulto , Algoritmos , Trastorno Autístico/diagnóstico , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Niño , Femenino , Humanos , Italia/epidemiología , Modelos Logísticos , Masculino , Análisis Multivariante , Oportunidad Relativa , Proyectos Piloto , Embarazo , Complicaciones del Embarazo/diagnóstico , Prevalencia , Medición de Riesgo , Factores de RiesgoRESUMEN
BACKGROUND: A high prevalence of a variety of gastrointestinal (GI) symptoms is frequently reported in patients with Autism Spectrum Disorders (ASD). The GI disturbances in ASD might be linked to gut dysbiosis representing the observable phenotype of a "gut-brain axis" disruption. The exploitation of strategies which can restore normal gut microbiota and reduce the gut production and absorption of toxins, such as probiotics addition/supplementation in a diet, may represent a non-pharmacological option in the treatment of GI disturbances in ASD. The aim of this randomized controlled trial is to determine the effects of supplementation with a probiotic mixture (Vivomixx®) in ASD children not only on specific GI symptoms, but also on the core deficits of the disorder, on cognitive and language development, and on brain function and connectivity. An ancillary aim is to evaluate possible effects of probiotic supplementation on urinary concentrations of phthalates (chemical pollutants) which have been previously linked to ASD. METHODS: A group of 100 preschoolers with ASD will be classified as belonging to a GI group or to a Non-GI (NGI) group on the basis of a symptom severity index specific to GI disorders. In order to obtain four arms, subjects belonging to the two groups (GI and NGI) will be blind randomized 1:1 to regular diet with probiotics or with placebo for 6 months. All participants will be assessed at baseline, after three months and after six months from baseline in order to evaluate the possible changes in: (1) GI symptoms; (2) autism symptoms severity; (3) affective and behavioral comorbid symptoms; (4) plasmatic, urinary and fecal biomarkers related to abnormal intestinal function; (5) neurophysiological patterns. DISCUSSION: The effects of treatments with probiotics on children with ASD need to be evaluated through rigorous controlled trials. Examining the impact of probiotics not only on clinical but also on neurophysiological patterns, the current trial sets out to provide new insights into the gut-brain connection in ASD patients. Moreover, results could add information to the relationship between phthalates levels, clinical features and neurophysiological patterns in ASD. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02708901 . Retrospectively registered: March 4, 2016.
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Trastorno del Espectro Autista/tratamiento farmacológico , Suplementos Dietéticos , Enfermedades Gastrointestinales/tratamiento farmacológico , Probióticos/uso terapéutico , Trastorno del Espectro Autista/complicaciones , Trastorno del Espectro Autista/microbiología , Encéfalo/metabolismo , Niño , Preescolar , Comorbilidad , Femenino , Enfermedades Gastrointestinales/complicaciones , Enfermedades Gastrointestinales/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Masculino , PrevalenciaRESUMEN
Interictal electroencephalogram (EEG) abnormalities are frequently associated with autism spectrum disorders (ASD), although their relationship with the clinical features of ASD, particularly the regressive onset, remains controversial. The aim of this study was to investigate whether the characteristics of interictal EEG abnormalities might help to distinguish and predict definite phenotypes within the heterogeneity of ASD. We reviewed the awake and sleep interictal EEGs of 220 individuals with idiopathic ASD, either with or without a history of seizures. EEG findings were analyzed with respect to a set of clinical variables to explore significant associations. A brain morphometry study was also carried out on a subgroup of patients. EEG abnormalities were seen in 154/220 individuals (70%) and were mostly focal (p < 0.01) with an anterior localization (p < 0.001). They were detected more frequently during sleep (p < 0.01), and were associated with a regressive onset of ASD (p < 0.05), particularly in individuals with focal temporal localization (p < 0.05). This association was also stronger in regressive patients with concurrent macrocephaly, together with a relative volumetric reduction of the right temporal cortex (p < 0.05). Indeed, concurrence of temporal EEG abnormalities, regression and macrocephaly might possibly define a distinct endophenotype of ASD. EEG-based endophenotypes could be useful to untangle the complexity of ASD, helping to establish anatomic or pathophysiologic subtypes of the disorder.
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Trastorno del Espectro Autista/fisiopatología , Discapacidades del Desarrollo/diagnóstico , Megalencefalia/fisiopatología , Convulsiones/diagnóstico , Lóbulo Temporal/fisiopatología , Trastorno del Espectro Autista/diagnóstico , Encéfalo/fisiopatología , Electroencefalografía , Femenino , Humanos , Masculino , Fenotipo , Convulsiones/complicaciones , SueñoRESUMEN
BACKGROUND: With a complex and extremely high clinical and genetic heterogeneity, autism spectrum disorders (ASD) are better dissected if one takes into account specific endophenotypes. Comorbidity of ASD with epilepsy (or paroxysmal EEG) has long been described and seems to have strong genetic background. Macrocephaly also represents a well-known endophenotype in subgroups of ASD individuals, which suggests pathogenic mechanisms accelerating brain growth in early development and predisposing to the disorder. We attempted to estimate the association of gene variants with neurodevelopmental disorders in patients with autism-epilepsy phenotype (AEP) and cranial overgrowth, analyzing two genes previously reported to be associated with autism and macrocephaly. METHODS: We analyzed the coding sequences and exon-intron boundaries of GLIALCAM, encoding an IgG-like cell adhesion protein, in 81 individuals with Autism Spectrum Disorders, either with or without comorbid epilepsy, paroxysmal EEG and/or macrocephaly, and the PTEN gene in the subsample with macrocephaly. RESULTS: Among 81 individuals with ASD, 31 had concurrent macrocephaly. Head circumference, moreover, was over the 99.7th percentile ("extreme" macrocephaly) in 6/31 (19%) patients. Whilst we detected in GLIALCAM several single nucleotide variants without clear pathogenic effects, we found a novel PTEN heterozygous frameshift mutation in one case with "extreme" macrocephaly, autism, intellectual disability and seizures. CONCLUSIONS: We did not find a clear association between GLIALCAM mutations and AEP-macrocephaly comorbidity. The identification of a novel frameshift variant of PTEN in a patient with "extreme" macrocephaly, autism, intellectual disability and seizures, confirms this gene as a major candidate in the ASD-macrocephaly endophenotype. The concurrence of epilepsy in the same patient also suggests that PTEN, and the downstream signaling pathway, might deserve to be investigated in autism-epilepsy comorbidity. Working on clinical endophenotypes might be of help to address genetic studies and establish actual causative correlations in autism-epilepsy.
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Anomalías Múltiples/genética , Trastorno Autístico/genética , Epilepsia/genética , Megalencefalia/genética , Fosfohidrolasa PTEN/genética , Proteínas/genética , Adolescente , Secuencia de Aminoácidos , Secuencia de Bases , Proteínas de Ciclo Celular , Niño , Preescolar , Análisis Mutacional de ADN , Femenino , Mutación del Sistema de Lectura , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Humanos , Masculino , Datos de Secuencia Molecular , Adulto JovenRESUMEN
Several studies showed that in the human brain specific premotor and parietal areas are activated during the execution and observation of motor acts. The activation of this premotor-parietal network displaying the so-called Mirror Mechanism (MM) was proposed to underpin basic forms of action understanding. However, the functional properties of the MM in children are still largely unknown. In order to address this issue, we recorded high-density EEG from 12 children (6 female, 6 male; average age 10.5, SD ±2.15). Data were collected when children observed video clips showing hands grasping objects in two different experimental conditions: (1) Full Vision, in which the motor act was fully visible; (2) Hidden, in which the interaction between the hand and the object was not visible. Event-related potentials (ERPs) and topographic map analyses were used to investigate the temporal pattern of the ERPs and their brain source of localization, employing a children template of the Montreal Neurological Institute. Results showed that two different parieto-premotor circuits are activated by the observation of object-related hand reaching-to-grasping motor acts in children. The first circuit comprises the ventral premotor and the inferior parietal cortices. The second one comprises the dorsal premotor and superior parietal cortices. The activation of both circuits is differently lateralized and modulated in time, and influenced by the amount of visual information available about the hand grasping-related portion of the observed motor acts.
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Potenciales Evocados Visuales , Lóbulo Frontal/fisiología , Actividad Motora , Lóbulo Parietal/fisiología , Niño , Electroencefalografía , Femenino , Humanos , MasculinoRESUMEN
A large number of studies have reported on the validity of autism spectrum disorder (ASD) screening procedures. An overall understanding of these studies' findings cannot be based solely on the level of internal validity of each, since screening instruments might perform differently according to certain factors in different settings. Europe has led the field with the development of the first screening tool and first prospective screening study of autism. This paper seeks to provide an overview of ASD screening studies and ongoing programmes across Europe, and identify variables that have influenced the outcomes of such studies. Results show that, to date, over 70,000 children have been screened in Europe using 18 different screening procedures. Differences among findings across studies have enabled us to identify ten factors that may influence screening results. Although it is impossible to draw firm conclusions as to which screening procedure is most effective, this analysis might facilitate the choice of a screening method that best fits a specific scenario, and this, in turn, may eventually improve early ASD detection procedures.