Melissa Monti

and 3 more

Several theories have been proposed about the default configuration of the brain’s networks underlying unisensory and multisensory processing abilities and the development of multisensory integration during childhood. Recent empirical findings from animal models and behavioral data collected from typically developing (TD) children and children with autism spectrum disorder (ASD), however, are consistent with the idea that in the immature brain, prior to systematic cross-sensory exposures typically encountered in everyday life, that the individual sensory systems interact in a competitive manner. Which neural architecture and mechanisms best describe the brain’s naïve configuration are still unknown. To fill this gap, this study investigates how sensory modalities interact in the young brain by comparing the predictions of two alternative biologically plausible neuro-computational models to empirical data. The neural substrates responsible for the altered development of multisensory integrative processes observed in ASD children are also investigated. Linking the framework suggested by empirical data to a plausible neural implementation, our results challenge the classical notion of cross-sensory brain organization at birth, whereby the various sensory pathways do not initially interact. Instead, we suggest that direct inhibitory interactions between sensory modalities are taking place in the immature brain, and we suggest that these inhibitory interactions play a crucial role in the altered multisensory perceptual abilities of children with autism.

Kathryn-Mary Wakim

and 2 more

Sensorimotor atypicalities are common in Autism Spectrum Disorder (ASD) and are often evident prior to classical ASD symptoms. Despite evidence of differences in neural processing during imitation in ASD, research on integrity of basic sensorimotor processing is surprisingly sparce. To address this gap in the literature, here we examined basic sensorimotor processing in autism by analyzing EEG data recorded from a large sample of children and adolescents while they performed an audio-visual speeded reaction time task. Using response-locked signal averaging, we investigated the neural processes associated with execution of a cued movement in a large sample of children and adolescents with ASD (n=84) and without ASD (n=84). Analyses focused on motor related brain responses that are well-characterized in adults: the late berichtsheft potential, the motor potential, and the reafferent potential. Group differences were examined in data parsed by age (6-9 years, 9-12 years, 12-15 years), sensory cue preceding the response (auditory, visual, bi-sensory audio-visual), and reaction time quartile. Overall, the data revealed robust sensorimotor neural responses in ASD. Nevertheless, subtle sensorimotor atypicalities were present in autistic children across all parcellations, and these differences were most prominent in the youngest group of children (age 6-9). Future studies focused on younger children are needed to understand if differences in basic sensorimotor processing are more prominent earlier in development in autism.