The Role of Attentional Disengagement On the Emergence of Joint Attention and Arousal Regulation: A Study of Infants At-Risk for ASD

Background: Impaired disengagement of attention is the earliest attentional deficit reported in infants at high-risk for autism (HRA) and may be associated with a later diagnosis of the autism spectrum disorder (ASD).  Efficient disengagement of attention plays a significant role in the development of both joint attention and arousal regulation.  Therefore, early deficits in attentional disengagement may result in the atypical development of both of these processes and contribute to the emergence of the heterogeneous ASD phenotype.

Objectives: To investigate the association between attentional disengagement, measured at 6-months, and development of joint attention, novelty processing, and arousal modulation (measured at 12 and 18 months) in HRA and low-risk comparison (LRC) infants.

Methods: HRA and LRC infants completed visits at 6, 9, 12, and 18 months of age.  An eye-tracking paradigm was used to assess the efficiency of attentional disengagement at 6 months (n = 24 HRA; n = 20 LRC).  Latency to disengage attention was measured as the time necessary to shift attention from a central fixation (i.e., a face) to a peripheral target.  Joint attention abilities were assessed using observational measures: the Communication and Symbolic Behavior Scales (CSBS) and the Autism Observation Scales for Infants (AOSI) at 12 months, and the Autism Diagnostic Observation Schedule (ADOS) at 18 months.  Arousal regulation was measured using a series of parent questionnaires: the Infant Behavior Questionnaire (IBQ) at 12 months, Toddler Behavior Assessment Questionnaire (TBAQ) at 18 months, and Infant Toddler Social Emotional Assessment (ITSEA) at 12 and 18 months.  Items and subscales for these measures were standardized and averaged to create joint attention and arousal regulation composite variables at 12 and 18 months.

Results: Latency to disengage attention at 6 months was not significantly different for HRA and LRC groups.  For the LRC group, but not the HRA group, faster disengagement latency was associated with better joint attention skills at 12, r(17) = .56, p < .05, and 18, r(18) = .44, p < .1, months. For the HRA group, slower attentional disengagement was related to poorer arousal regulation at 12 months, r(20) = .70, p < .01.

Conclusions: Efficient disengagement results in the adaptive allocation of attention (e.g., sharing attention with a communicative partner; joint attention) and facilitates early arousal regulation. Preliminary results suggest that faster attentional disengagement is associated with more skillful joint attention abilities at 12 and 18 months in LRC but not HRA infants.  In contrast, for the HRA group, increased latency to disengage attention was associated with greater aversion to novelty. Although preliminary, our findings suggest that atypical attentional disengagement may have sequelae that, in combination with other primary disturbances, result in the heterogeneous phenotypic end-state associated with ASD.