Conceptualizing the substrates and sequelae of decreased sound tolerance as a developmental cascade: A pilot study.

This study followed babies who had autistic siblings (higher chance of being autistic) and compared them to other babies. Researchers wanted to understand how sound sensitivity develops and affects mental health. They found that babies with autistic siblings, especially those later diagnosed with autism, showed more sound sensitivity problems. Early sensitivity to touch and other senses predicted later sound problems, which then led to more anxiety.

This pilot study prospectively examined the development of decreased sound tolerance (DST) in infants at high likelihood for autism (younger siblings of autistic children) compared to lower-likelihood infants. The research explored whether early brain activity patterns and sensory hyperresponsiveness predict DST development, and how DST relates to later anxiety. Results showed DST symptoms were elevated in high-likelihood infants, particularly those later diagnosed with autism. The study found that early sensory hyperresponsiveness predicted later DST, which in turn predicted anxiety symptoms.

However, early brain gamma power did not significantly predict sensory outcomes, suggesting alternative developmental pathways may be involved.

Early identification of sensory hyperresponsiveness in at-risk infants may help predict and prevent sound tolerance difficulties and associated anxiety. This supports implementing sensory assessments and interventions early in development, particularly for siblings of autistic children.

This is a pilot study with unreported sample size, limiting generalizability. The study design and methodology details are not provided in the abstract, making it difficult to assess methodological rigor and potential confounding factors.

A growing body of research has shown that decreased sound tolerance (DST) is highly prevalent and impacts the mental health of affected individuals. Recent work has shown this is especially true for autistic individuals. The extant literature has been limited, however, by a focus on DST relatively late in life. Consequently, at present we know little about when and how DST emerges and produces cascading effects on mental health.

In this pilot study, we prospectively followed infants at high likelihood for autism, and thus hypothetically for DST, based on their status as younger siblings of autistic children (Sibs-Autism) and infants at lower, general population-level likelihood for these conditions (Sibs-NA) to determine whether (a) DST symptomatology differs based on autism likelihood status and/or diagnostic outcome; (b) indices of early resting brain states, specifically gamma power, predict sensory hyperresponsiveness and DST; (c) sensory hyperresponsiveness predicts DST symptomatology; (d) DST symptomatology predicts anxiety; and (e) if the aforementioned associations vary by familial likelihood for autism or later autism status. Preliminary results indicate that DST symptoms are elevated in Sibs-Autism, particularly those who go on to receive a diagnosis of autism, relative to Sibs-NA. Gamma power is not significantly associated with later sensory hyperresponsiveness or DST, but hyperresponsiveness is associated with later DST, which is associated with later anxiety in Sibs-Autism.