Executive functions and core symptoms in autistic individuals

Executive Functions (EFs) refer to processes that enable individuals to modify and regulate their behaviors and thoughts, adapting them to new stimuli. Current literature emphasizes differences in these abilities between Autistic individuals and neurotypical individuals. Moreover, these processes seem to be related to the restricted and repetitive behaviors, rather than socio-communicative abilities. Considering sex-differences research presents contrasting results when these are evaluated with instruments standardized on the neurotypical population, no distinctions are evident in parent and teachers reports. Objectives - To investigate the association between the core symptoms of ASD and neuropsychological tests’ scores used to assess planning, problem-solving, cognitive flexibility and feedback processing. - To explore sex-differences in EFs as previous literature shows contrasting results. Methods Participants N=60 (49 males, 11 females) individuals (Mean chronological age=125 months, SD=37.60m) participated in our study. Individuals had a confirmed diagnosis of ASD, without associated language or intellectual difficulties, or comorbidities. Measures Certified psychologists conducted a comprehensive diagnostic assessment, employing neuropsychological tests and the Autism Diagnostic Observation Schedule-2 (ADOS-2). Cognitive profiles were evaluated using the Wechsler Scales, and Executive Functions (EFs) were assessed through the Tower of London (TOL) and the Wisconsin Card Sorting Test (WCST). The TOL gauges planning and problem-solving abilities, whereas the WCST evaluates cognitive flexibility and feedback processing. Analysis Linear models were fitted to test the association between EFs scores and clinical variables, adjusted for confounding variables individuated with preliminary correlations analysis. Bonferroni’s multiple comparison corrections were applied. To study sex-differences, we individuated two subsamples (11 females, 11 males), matched based on age and IQ, and applied inferential statistics. Results No association between executive functioning and social symptoms were found, controlling for the effect of Performance and Verbal intelligence quotients. A significant association between planning and problem-solving scores measured with the Tower of London (TOL-Total Score) and the RRBs was found, controlling for the effect of Performance and Verbal Intelligence Quotients. In particular the model was significant F(3,49)=6.78, p-adj=0.02, R^2= 0.25. RRB is the only significant predictor β=-3.68, p=0.002. No significant associations were found between cognitive flexibility and feedback processing, and RRBs. No significant sex-differences emerged regarding EFs. Conclusions We found a significant association between planning and problem-solving abilities and RRBs, this should be taken into consideration in the school context, providing adequate support and planning targeted interventions. Moreover, matching to age and IQ, a subgroup of females and males did not show differences regarding EFs, this is in line with literature on the ecological evaluation of EFs. It's crucial to note that the instruments used in our study were not standardized for individuals with Autism Spectrum Disorder (ASD). Consequently, these tools might not fully capture the challenges faced by children with ASD. Therefore, our results underscore the urgency of developing and standardizing EFs assessment instruments tailored specifically for the autistic population. This development holds significant implications for diagnostic assessments, enabling the acquisition of more precise psychodiagnostic profiles. Consequently, this can lead to highly personalized treatment approaches.