Interpersonal Movement Coordination in Adults with Autism Spectrum Disorder (ASD): A Potential Tool for Addressing ‘Female Camouflage’?

Background: When individuals engage in social interactions, they coordinate their nonverbal movements such as facial expressions and gestures. This movement coordination is associated with increased rapport and social connection between partners (Miles et al., 2009). Emerging research in ASD has suggested atypical movement coordination in the population (Zampella & Bennetto, 2018), but individual differences are yet to be examined. Interestingly, recent work demonstrates that females with ASD present more typical socio-communicative behaviours (e.g., gestures) relative to males. This strength in females with ASD may ‘camouflage’ other diagnostic features, resulting in under-diagnosis (Rynkiewicz et al., 2016). Here, we used a novel movement analysis method to explore whether interpersonal movement coordination, a hallmark of successful communication, may differ between males and females with ASD.

Objectives: 1) To utilize a novel, optic-flow methodology to determine whether movement coordination during interaction differs between males and females with ASD, and 2) evaluate how this compares to potential sex differences in movement coordination in neurotypical (NT) adults

Methods: Thirteen adults (3 females; Age: 18-24 years) with ASD without intellectual disability participated. Twenty-six participants will be recruited as NT controls. Participants completed the ADOS-2, Module 4 with a research-reliable administrator while being video-recorded. Semi-structured interview sections of the ADOS (e.g., questions about social interactions difficulties) were selected for analysis. The control sample will be asked the same semi-structured interview questions. Movement coordination was analyzed using Correlation Map Analysis (CMA; Barbosa et al., 2012). CMA uses a standardized optical flow method to assess movement within regions based on changes in pixels across video frames. A moving-window is used to calculate instantaneous correlation between regions. A higher correlation value corresponds to greater coordination. Whole-body regions were identified around the participant and the experimenter to assess movement coordination.

Results: Females with ASD demonstrated greater movement coordination within a much smaller range (Range=.75-.82) than the males (Range=.35-.84; Figure 1). This difference is striking because males and females were similar with respect to age, verbal and non-verbal IQ. Moreover, females exhibited greater coordination despite having higher symptom severity than males (ADOS median calibrated severity score female=9, male=7; Figure 2). Movement coordination between the ASD group and the NT group will be compared. Based on previous work (e.g., Zampella & Bennetto, 2018), we expect that ASD participants will present lower movement coordination compared to NT participants. We also predict a main effect of gender, based on prior results using other methodologies (Hermans et al., 2009). Given that females with ASD present more typical socio-communicative behaviour, we expect a GenderXGroup interaction, such that the difference in coordination between ASD and NT males will be greater than the difference between ASD and NT females.

Conclusions: These preliminary results suggest that there may be intriguing differences in interpersonal movement coordination between males and females with ASD, which need to be investigated in larger samples. Given that females with ASD often ‘camouflage’ other diagnostic features with their relatively typical socio-communicative behaviours, investigating movement coordination during interaction may provide a tool for better understanding gender differences in ASD.