Beyond Gaze: Affective Synchrony and Sensory-Linked Interactional Profiles as Early Markers of Autism Risk.
Shared emotion beats eye contact for spotting autism risk before age two.
01Research in Context
What this study did
Lan et al. watched babies and caregivers play at home. They tracked two things: mutual gaze and affective synchrony. Affective synchrony means baby and adult smile, frown, or coo at the same time.
They followed the babies until age three to see who later got an autism diagnosis. The team wanted to know which early sign—gaze or synchrony—better predicted the outcome.
What they found
Low synchrony at 6–18 months forecasted autism, but mutual gaze did not. A baby could look at Mom’s eyes yet still miss her smile timing. The lack of shared emotion, not eye contact, flagged risk.
How this fits with other research
Rollins et al. (2020) taught toddlers with autism to increase mutual gaze and saw social gains. That result seems to clash with Lan’s finding that gaze alone is weak. The difference: Rollins trained older kids to use gaze in play; Lan measured natural gaze in babies. Gaze training can still help, but early screening needs the deeper layer of synchrony.
Lifshitz et al. (2014) first showed that joint-attention bids without smiling predicted later autism symptoms. Lan’s work widens that lens from single smiles to whole interaction rhythms.
Zhao et al. (2026) used a children’s song video and also found weaker gaze-stimulus synchrony in toddlers with autism. Lan moves the marker even earlier, to live face-to-face play in infancy.
Why it matters
When you screen infants, watch for shared smiles and vocal turns, not just eye contact. A baby who looks but doesn’t sync may need referral even if gaze looks fine. Add synchrony probes—simple peek-a-boo games—to your assessment toolkit.
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02At a glance
03Original abstract
Identifying early markers for autism spectrum disorder (ASD) is a clinical priority. This study investigated interpersonal affect synchrony (IAS) as a measure of interactional quality in a longitudinal cohort of 90 high-risk infants. We aimed to disentangle its contribution from mutual gaze and identify data-driven social interaction profiles linked to sensory traits. Parent-infant interactions were recorded at 6-18 months; IAS was quantified using Cross-Recurrence Quantification Analysis, and ASD outcomes were determined at 18-24 months. Infants later diagnosed with ASD (n = 25) showed significantly lower IAS (F(1,84) = 5.89, p FDR = 0.023) and synchrony stability (F(1,84) = 5.37, p FDR = 0.023) than non-diagnosed infants (n = 65), yet the groups did not differ in mutual gaze (p = 0.200). Logistic regression analysis further showed that IAS (OR = 0.561, p FDR = 0.038) and synchrony stability (OR = 0.013, p FDR = 0.038) both significantly predict clinical outcome. K-means clustering revealed three profiles: "High Gaze-High Synchrony," "Mid Gaze-Low Synchrony," and "Low Gaze-High Synchrony." The "Mid Gaze-Low Synchrony" profile was significantly associated with a later ASD diagnosis (p adj = 0.031), while the "Low Gaze-High Synchrony" profile was linked to higher sensation-seeking traits (p adj = 0.028). The quality of parent-infant affective connection is a more robust early marker for ASD than the quantity of mutual gaze. These findings reveal critical heterogeneity, identifying a high-risk "gaze without engagement" pattern and a potential adaptive pathway to synchrony, underscoring the need for individualized strategies in early screening and intervention.
Autism research : official journal of the International Society for Autism Research, 2026 · doi:10.1002/aur.70209