Fig. 2: Topographical organization of global motion processing is different in infants who have high levels of autism symptoms in toddlerhood.

a More lateralized activation in the coherent motion condition was associated with higher autistic symptoms (ADOS-2 total scores at 36 months) in the overall EASE sample (r = 0.465, ***p < 0.001, n = 55), as well as in the EASE EL group (r = 1.448, **p = 0.004, n = 39). These were confirmed with a linear regression model (β = 7.22, **p = 0.005, partial η² = 0.170, n = 55) which also revealed no moderation by sex or autism-likelihood group (both p > 0.20). No association was found for the other conditions (all p > 0.25). a inset. Replication in an independent sub-sample of infants at elevated likelihood of autism who partook in ADOS-2 session at 24 months but not at 36 months (r = 0.596, *p = 0.027, n = 11, one-tailed). b Infants who went on to develop high levels of autistic symptoms at 36 months (EL high-ADOS, n = 14) according to pre-established clinical cut offs (see main text) had more lateralized global motion processing than infants at elevated likelihood with few autistic symptoms (EL low-ADOS: d = 0.25, *p = 0.029, n = 25), infants at low likelihood for autism (LL controls: d = 0.33, **p = 0.002, n = 16) and the larger community twin sample (BATSS: d = 0.31, **p = 0.003, n = 452), but no difference was found between these three latter groups (all p > 0.50). Boxplots show the sample median, and the first and third quartiles; whiskers show minimum and maximum (±1.5 s.d.); dots are outliers (±1.96 s.d.). Planned group comparisons done with linear mixed model and EMM effect-size analysis. c Comparison of activation across the nine AOIs between the Normative Sample and EL-high ADOS group. During global motion processing, EEG activity in the latter group was characterized by atypically strong extreme left lateral activation (AOIs A1 and A2: M = −0.120, **p = 0.009, d = −0.10 and M = −0.095, *p = 0.026, d = −0.08, respectively) and atypically weak midline activation (AOIs A4 and A5: M = 0.085, *p = 0.044, d = 0.07 and M = 0.100, *p = 0.026, d = 0.08, respectively). (Notes: *p < 0.05; **p < 0.01; ***p < 0.001, for blue asterisks in b and c; all p values are Benjamini-Hochberg-corrected). Data from the Normative Sample group (n = 473) is plotted as mean, 95%-C.I. (inner band, darker shade) and 99.5%-C.I. (outer band, lighter shade). Data from the EL high-ADOS group (n = 14) are plotted as mean & 95%-C.I. (error bars) along with the individual data points (shaded). More detailed activation plots for the Normative Sample are provided in Supplementary Fig. 2. Observe here that confidence intervals for the Normative Sample are comparatively very small due to its much bigger sample size.