A quarterly publication of the Autism Research Institute

The Autism Research Review International is quarterly publication of the Autism Research Institute

Summer, 2018 | Number 3, Volume 32

Babies’ early responses to peek-a-boo, other social stimuli may point to later ASD diagnosis

Babies with lower levels of brain activity in response to social stimuli have an increased likelihood of receiving a later diagnosis of autism spectrum disorder (ASD), according to a new study. 

In the study, Sarah Lloyd-Fox and colleagues used a neuroimaging technology called functional near-infrared spectroscopy to study the brain activity of 20 infants at elevated risk for autism (because they had at least one older sibling with ASD) and 16 low-risk infants, all between four and six months of age. The researchers explored how the brain activity of the infants changed in response to videos showing social scenes (for instance, people playing peek-a-boo) and non-social images of cars and other objects. In addition, they studied the infants’ responses to human sounds, such as coughing or laughing, and to non-human sounds, such as bells or running water. 

The researchers report that compared to low-risk infants, babies later diagnosed with ASD showed reduced activation to visual social stimuli across the inferior frontal and posterior temporal regions of the cortex. In addition, compared to either low-risk infants or high-risk infants who did not develop ASD, the children later diagnosed with ASD showed reduced activation to vocal sounds and enhanced activation to non-vocal sounds within the left-lateralized temporal regions. Moreover, the researchers say, “The degree of activation to both the visual and auditory stimuli correlated with parent-reported ASD symptomology in toddlerhood.” 

Lloyd-Fox comments, “We have found an early indication of different patterns of brain activity in infants who go on to develop ASD from an early age. Given the importance of responding to others in our social world, it is possible that different attentional biases may particularly impact the development of social brain responses, which can continue to affect the child’s developmental trajectory as they get older. Identifying early patterns of altered development which may later associate with ASD is important because it will allow doctors to offer earlier interventions and provide families with earlier avenues for support. This might mean giving the child and parents new strategies to reengage their attention toward important social cues and learn different ways of interacting.” 

The researchers caution that their findings are preliminary, but note that they “highlight the need for further work interrogating atypical processing in early infancy and how it may relate to later social interaction and communication difficulties characteristic of ASD.”


“Cortical responses before 6 months of life associate with later autism,” S. Lloyd-Fox, A. Blasi, G. Pasco, T. Gliga, E. J. H. Jones, D. G. M. Murphy, C. E. Elwell, T. Charman, and M. H. Johnson, European Journal of Neuroscience, Vol. 47, pp. 736-49, 2018 (free online). Address: Sarah Lloyd-Fox, Centre for Brain and Cognitive Development, Birkbeck, University of London, Malet St., WC1E 7HX, London, UK, [email protected]


“First signs of autism appear in infancy,” news release, University College London, August 23, 2018.