Over the last years, researchers have been looking for biomarkers for autism spectrum disorder (ASD). Biomarkers can help early diagnosis and understand the mechanisms that underlie ASD. A marker that only recently started to get more attention is heart rate. Heart rate and heart rate variability, regulated by the autonomic nervous system, can be an indicator of arousal, attention processes and has been suggested as a transdiagnostic biomarker. However, studies looking at heart rate in ASD have led to mixed results with some showing difference and others do not and only few have looked at young children or infants with an increased likelihood for a diagnosis. Finding associations between biomarkers and ASD symptoms might be a more fruitful approach than looking for group differences alone. Additionally, we should consider the reliability of physiological measures before we can use them as reliable biomarkers.
The work I will be presenting is based on my PhD thesis and includes two samples: a sample of pre-schoolers (2-4 year olds) with a diagnosis and a sample of infants with a family history of ASD (British Autism Study of Infant Siblings – BASIS) at three time points in infancy. I will look at group differences in heart rate and heart rate variability and their associations with language development, social abilities and executive function skills.