Correlation between Autistic Traits and Gait Characteristics while Two Persons Walk Toward Each Other

Neurotypicals with higher autistic traits have delayed visual processing of an approaching life-sized avatar's gait: an event-related potentials study

Introduction

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, which is reportedly related to difficulties in the visual processing of human motion, such as biological motion and gestures. Moreover, neurotypical (here, we mention it as individuals without a diagnosis) adults with autistic traits are clumsier than those without autistic traits when passing by others. It is still unclear whether the clumsiness derived from atypical visual processing of another's approaching gait motion. We aim to address this question by investigating the association between autistic traits in neurotypical adults and the visual processing of an approaching life-sized avatar's gait.

Methods

We clarified a typical visual motion processing and autistic traits in daily life in 26 neurotypical adults by analyzing the subthreshold autism trait questionnaire (SATQ) score, a 24-item self-report scale of ASD, and event-related potentials (ERPs) in response to walking motion of a passing avatar. Videos of walking life-sized virtual avatars approaching and retreating were presented as visual stimuli.

Results and discussion

The association between the participants' SATQ scores and the latencies and amplitudes of the ERPs was examined. ERP components (N170 and P200) components were identified at T5 and T6 electrodes. Participants reporting higher SATQ scores had longer latencies of P200 at T6 and lower amplitudes of P200 at T5 and T6 electrodes for the approaching avatar than those reporting lower SATQ scores. These findings indicate that adults with autistic traits have delayed and less sensitive visual processing of the approaching avatar. It suggests that while passing another person, these individuals have atypical visual processing of their approach. This study may contribute to elucidating autistic traits from the perspective of visual processing in an environment simulating daily life.

Gait Perception of Life-Size Point-Light Walker is Associated with Autistic Traits: Evidence from Event-Related Evoked Potentials

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by a combination of atypicalities in social cognition. Previous studies showed that people with autistic traits have atypicality in motion perception on a point-light display by measuring visual event-related potentials (ERPs). Although some studies have focused on the association between motion perception and autistic traits, visual ERPs to biological motion as large as actual person have not been investigated. Measuring brain activity in a real-life environment help us to understand the difficulties showed in daily life by people with autistic traits. In this study, we investigated the association between gait perception and autistic traits by measuring ERPs during video observation of approaching and receding life-sized point-light walkers (PLW s). ERPs were measured using an 8-channel EEG system in 22 adults. The multiple regression analyses were conducted to assess association between the Subthreshold Autism Trait Questionnaire (SATQ) score and the ERP amplitude or latency. As the results, we found that the higher SATQ score could be explained by the longer latency of N1 on the occipitotemporal area. These findings suggested that people with autistic traits have difficulty in perceiving the approach of others in daily life.

Correlation Between Gait Perception and Autistic Traits in the General Population: A Study on Event-Related Evoked Potentials

Previous studies have shown that people with autistic traits have difficulties in motion perception, such as human gait as depicted on a point-light display. A recent study reported that adults with autism spectrum disorders showed atypical visual event-related evoked potentials (ERPs) in response to radial optic flow. To determine the correlation between gait perception and autistic traits in the general population, the present study recorded ERPs time-locked to the onset of approaching and receding point-light walkers. ERPs were measured using an 8-channel system in 19 adults and the correlation between the ERP components and the Subthreshold Autism Trait Questionnaire (SATQ) score were assessed to quantitatively measure autistic traits in the general population. The results showed that the higher SATQ score was, the longer the latency of the ERP component for an approaching walker was. In conclusion, people with autistic traits have trouble perceiving the approach of other people.