Reciprocal Associations between Language Ability and Social Functioning Development over a Two-Year Period in Young Pre-Verbal Children with Autism Spectrum Disorder

Background: Extant research involving young children with ASD has examined developmental trajectories of language ability and social functioning separately, with little focus on relations between these domains across early childhood (Bennett et al., 2015). Pre-verbal young children with ASD are of particular clinical relevance, given that greater language abilities at school entry have been shown to predict positive long-term adjustment in language and social functioning (Tager-Flusberg & Kasari, 2013). Since attention to and engagement with social contexts is necessary for language development, and growing language skills can facilitate further social engagement, examining reciprocal relations between social and language functioning in early development among pre-verbal children with ASD could inform intervention efforts. Further, more optimal nonverbal cognitive functioning, autism symptom severity, and joint attention skills have been associated with gains in both language ability and social functioning (Anderson et al., 2007, 2009; Thurm et al., 2007).

Objectives: We examined reciprocal associations between language ability and social functioning in a sample of young pre-verbal children with ASD over a two-year period. Moderating effects of baseline nonverbal cognitive functioning, initiation of and response to joint attention, and autism symptom severity on these associations were explored.

Methods: Participants were 90 pre-verbal children (21 girls) with ASD confirmed at two assessments: 1) 18 to 33 months of age (T1: M = 28 ± 4 months) and 2) 29 to 51 months (T2: M = 41 ± 4 months). Fifty-six children were assessed one year after T2 (T3: 43 to 66 months; M = 52 ± 5 months). Missing T3 data was imputed for 34 children. Pre-verbal status was defined at T1 by t-scores below 30 on the Mullen Scales of Early Learning (Mullen) expressive language scale, corresponding to the “Very Low” descriptive category. Nonverbal cognitive functioning was derived from T1 Mullen Visual Reception and Fine Motor subscales. Social functioning was assessed with the original parent-report Vineland Adaptive Behavior Socialization scale. Autism symptom severity was measured with T1 Autism Diagnostic Observation Schedule algorithm total score. Initiation and response to joint attention was assessed with T1 Early Social Communication Scales. Multi-group cross-lagged panel analyses examined reciprocal associations between language ability and social functioning and potential moderators.

Results: Cross-lagged panel analyses revealed significant within-time correlations and within-domain autoregressive paths over time. All added reciprocal paths were significant (Fig. 1). Nonverbal cognitive functioning moderated T1 to T2 and T2 to T3 autoregressive language paths (Fig. 2a). Autism symptom severity moderated T2 to T3 autoregressive language and social functioning paths (Fig. 2b). Joint attention indices did not moderate.

Conclusions: For young pre-verbal children with ASD, language ability and social functioning appear to exert concurrent and cascading reciprocal developmental influences. Nonverbal cognitive functioning and autism symptom severity change the magnitude of these relations (Ellis Weismer & Kover, 2015). Findings support potential amplification of intervention effects from simultaneous targeting of language and social domains for this population. Increased attention to nonverbal cognitive functioning and autism symptom severity in intervention research may also inform targeted intervention approaches for young pre-verbal children with ASD.