Neonatal Brainstem Function and 4‐Month Arousal‐Modulated Attention Are Jointly Associated With Autism

Abstract

Lay Abstract A stronger preference for high rates of stimulation when tested after feeding at four months of age has been reported in Neonatal Intensive Care Unit (NICU) graduates who later were diagnosed with autism relative to those who were not. This visual preference is typical of newborns, is likely mediated by arousal systems in the brainstem, and should no longer be present by four months. The fact that it was so persistent in babies who later developed autism suggested they may have had atypical brainstem development or functioning. There exists a group of newborns who initially fail Auditory Brainstem Response screens (ABRs; a measure of the integrity of their brainstem auditory pathways) but eventually recover by hospital discharge suggesting they have atypical brainstem development. We therefore examined the extent to which this problem with ABR functioning along with four-month-olds’ preference for high rates of stimulation predicts the later occurrence of autism in toddlers and preschoolers. We found that preference for higher rates of stimulation at four months was highly associated with later measures of autism severity and with language development problems but only in those who had initially abnormal ABRs. It was concluded that the joint occurrence of initially abnormal neonatal ABRs and preference for more stimulation at four months, both indices of early brainstem dysfunction, may be a marker for the development of autism. Scientific Abstract The authors evaluated the contribution of initially abnormal neonatal Auditory Brainstem Responses (ABRs) and four month Arousal Modulated Attention visual preference to later Autism Spectrum Disorder (ASD) behaviors in Neonatal Intensive Care Unit (NICU) graduates. A longitudinal study design was used to compare NICU graduates with normal ABRs (n=28) to those with initially abnormal ABRs (n=46) that later resolved. At four months post-term-age, visual preference (measured after feeding) for random check patterns flashing at 1, 3, or 8 Hz, and gestational age (GA) served as additional predictors. Outcome measures were PDD Behavior Inventory (PDDBI) scores at 3.4 (SD=1.2) years, and DQs obtained around the same age with the Griffiths Mental Development Scales (GMDS). Preferences for higher rates of stimulation at four months were highly correlated with PDDBI scores (all p values <.01), and the GMDS Hearing and Speech DQ but only in those with initially abnormal ABRs. Effects were strongest for a PDDBI social competence measure most associated with a diagnosis of autism. For those with abnormal ABRs, increases in preference for higher rates of stimulation as infants were linked to non-linear increases in severity of ASD at three years and to an ASD diagnosis. Abnormal ABRs were associated with later reports of repetitive and ritualistic behaviors irrespective of four month preference for stimulation. The joint occurrence of initially abnormal neonatal ABRs and preference for more stimulation at four months, both indices of early brainstem dysfunction, ma...

Increases in Arousal are More Long‐Lasting than Decreases in Arousal: On Homeostatic Failures During Emotion Regulation in Infancy

“…In future, it will be interesting to investigate this question in more detail in order to ascertain whether there is an optimum level between over‐ and understimulation (cf Gardner & Karmel, ; Kidd, Piantadosi, & Aslin, ) and how this differs between individuals. This may relate to previous research that has investigated early individual differences in infants’ preferences for high and low external stimulation from both a state (Gardner & Karmel, ; Geva, Gardner, & Karmel, ) and trait (Cohen et al., ; Gardner, Karmel, Magnano, Norton, & Brown, ; Gardner et al., ; Geva, Schreiber, Segal‐Caspi, & Markys‐Shiffman, ) perspective.…”

Neonatal brainstem dysfunction after preterm birth predicts behavioral inhibition

“…Importantly, a verbal component may be considered. Deviant ABR were reported to predict impaired social interactions, particularly in the context of language disorders and a risk for autism (Cohen et al, 2013). Future study may explore further verbal outcome of neonatal CBSF.…”

Speech Disturbs Face Scanning in 6-Month-Old Infants Who Develop Autism Spectrum Disorder

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