Reduced visual evoked potential amplitude in autism spectrum disorder, a variability effect?

Klara Kovarski (1) , Joëlle Malvy (2, 1) , Raoul Khanna (1) , Sophie Arsene (2) , Magali Batty (3) , Marianne Latinus (1)

1 iBraiN - Imaging, Brain & Neuropsychiatry
2 CHRU Tours - Centre Hospitalier Régional Universitaire de Tours
3 CERPPS - Centre d’Etudes et de Recherches en Psychopathologie et Psychologie de la Santé

Atypical sensory behaviours represent a core symptom of autism spectrum disorder (ASD). Investigating early visual processing is crucial to deepen our understanding of higher-level processes. Visual evoked potentials (VEPs) to pattern-reversal checkerboards were recorded in ASD children and age-matched controls. Peak analysis of the P100 component and two types of single-trial analyses were carried out. P100 amplitude was reduced in the ASD group, consistent with previous reports. The analysis of the proportion of trials with a positive activity in the latency range of the P100, measuring inter-trial (in)consistency, allowed identifying two subgroups of ASD participants: the first group, as control children, showed a high inter-trial consistency, whereas the other group showed an inter-trial inconsistency. Analysis of median absolute deviation of single-trial P100 (st-P100) latencies revealed an increased latency variability in the ASD group. Both single-trial analyses revealed increased variability in a subset of children with ASD. To control for this variability, VEPs were reconstructed by including only positive trials or trials with homogeneous st-P100 latencies. These control analyses abolished group differences, confirming that the reduced P100 amplitude results from increased inter-trial variability in ASD. This increased variability in ASD supports the neural noise theory. The existence of subgroups in ASD suggests that the neural response variability is not a genuine characteristic of the entire autistic spectrum, but rather characterized subgroups of children. Exploring the relationship between sensory responsiveness and inter-trial variability could provide more precise bioclinical profiles in children with ASD, and complete the functional diagnostic crucial for the development of individualized therapeutical projects.

Domaines: Psychologie; Neurosciences

Klara Kovarski, Joëlle Malvy, Raoul Khanna, Sophie Arsene, Magali Batty, et al.. Reduced visual evoked potential amplitude in autism spectrum disorder, a variability effect?. Translational Psychiatry, 2019, 9 (1), pp.341. ⟨10.1038/s41398-019-0672-6⟩. ⟨hal-02544989v2⟩