A group of students from London Academy of Excellence - Stratford, along with Orbyts Fellow Anita Song from the Centre for Brain and Cognitive Development at Birkbeck, University of London, have investigated brain activity in infants with a family history of autism and ADHD using non-invasive methods. The study aimed to shed light on early differences in brain-behaviour associations in infants at an elevated likelihood of neurodevelopmental conditions.

The research focused on the Theta Beta Ratio (TBR), a widely studied measure in Attention Deficit and Hyperactivity Disorder (ADHD), which represents the ratio between EEG power in the theta and beta frequency ranges. The study found that babies more likely to develop ADHD exhibited a different balance of slow and fast brainwaves. Specifically, TBR at 10 months was lower in infants with an elevated likelihood of ADHD, based on family status, compared to those with a typical likelihood. However, this 10-month TBR did not predict ADHD outcome at 3 years, suggesting it reflects familial likelihood rather than clinical outcome at that age.

Additionally, the study explored the link between differences in sensory sensitivity, commonly observed in autism and ADHD, and EEG power. The findings indicated that babies who responded differently to touch, lights, and sounds showed changes in the strength of certain brainwaves. Two-year-old toddlers with atypical sensory profiles—meaning their sensitivity was outside the typical range (hyper- or hyposensitive)—displayed lower theta and higher beta EEG power compared to those with typical sensory sensitivities. This could be attributed to arousal dysregulation, altered sensory filtering, or compensation for internal stress triggered by external stimuli, leading to different adaptations during early neurodevelopment.

This research, with support from a consortium of charities led by Autistica, the Medical Research Council, and the EU-AIMS project, provides valuable insights into the early brain signatures associated with ADHD likelihood and sensory processing in infants and toddlers!