Are Variations in Narrative Language Reflected in Early Auditory Processing Via ABR?

Background: Autism Spectrum Disorder (ASD) is a developmental disorder affecting both social interaction and verbal communication (APA, 2013). Children with ASD demonstrate differences or delays in language development compared to typically developing (TD) children (Tek et al., 2013), as well as in aspects of brain development such as auditory brainstem response (ABR, Russo et al., 2008, Pillion et al. 2018). ABR is a measure of early auditory processing characterized by five waveforms occurring in various locations of the brainstem in response to a stimulus onset. Recent research has demonstrated that children with higher ABR stability show enhanced phonological and grammatical performance on experimental tests (Tecoulesco et al., 2018). Children with ASD also demonstrate challenges with narrative language, which seems less coherent and includes fewer causal connectors compared to TD peers (Baixuali et al., 2016). The current study investigates connections between measures of narrative language and concurrent ABR processing.

Objectives: The current study investigates how disturbances in early stages of auditory processing might account for variability in the narrative language of children with ASD, including lexical, discourse, and coherence measures.

Methods: Participants included twelve children with ASD; six have been completely coded. Their average age was 12.33 years (SD=3.01), average Matrices subtest score was 19.50 (SD=8.87), CELF scores were 36.67 (SD=6.31; FS) and 30.67 (SD=5.20; WC), and ADOS scores were 8.17 (SD=4.36). Children were assessed in their home; the narratives came from the ADOS tasks, including Objects, Cartoon, Tuesday storybook. Narratives were transcribed, and coded using CLAN. The Cartoon and Objects narratives were rated by seven naïve adults on story coherence, using a Likert scale (1 (easily followed) to 7 (very difficult to follow)). ABRs were recorded from scalp electrodes with a click stimulus (31.1/sec, 2000 trials) and a 40 millisecond “da” stimulus (10.9/sec, 6000 trials) presented at 80 dB SPL to the right ear. Wave V latency plus click and /da/ response stability (Fisher transformed Pearson’s r-values), served as the primary dependent measures of sound encoding.

Results: Correlations performed between the ABR stability measures and language measures (total words, noun types, utterances, conjunctions, discourse markers) revealed consistently negative relationships: children with ASD who produced more of each of these measures in their narratives showed lower click and /da/ stability (-.981 < rs < -.823, ps < .01). No significant relationships emerged between the language measures and the ABR latency measures; however, the ratings of narrative coherence correlated marginally significantly and positively with click latency (r = .731, p = .099).

Conclusions: Significant relationships emerged between children with ASD’s narrative language and their early auditory processing. The directionality of most of these relationships was surprising, as children who produced more varied words in a number of categories showed less ABR stability. However, children whose narratives were rated as less coherent tended to have longer ABR latencies. Caution is needed before drawing conclusions because of small sample size as well as a limited number of language measures. Future analyses will include twice as many participants, plus additional grammatical measures from the narratives.