Coregistration of EEG and eye-tracking in infants and developing populations

Infants cannot be instructed where to look; therefore, infant researchers rely on observation of their participant's gaze to make inferences about their cognitive processes. They therefore started studying infant attention in the real world from early on. Developmental researchers were early adopters of methods combining observations of gaze and behaviour with electroencephalography (EEG) to study attention and other cognitive functions. However, the direct combination of eye-tracking methods and EEG to test infants is still rare, as it includes specific challenges. The current article reviews the development of co-registration research in infancy. It points out specific challenges of co-registration in infant research and suggests ways to overcome them. It ends with recommendations for implementing the co-registration of EEG and eye-tracking in infant research to maximise the benefits of the two measures and their combination and to orient on Open Science principles while doing so. In summary, this work shows that the co-registration of EEG and eye-tracking in infant research can be beneficial to studying natural and real-world behaviour despite its challenges.

Simulating interaction: Using gaze-contingent eye-tracking to measure the reward value of social signals in toddlers with and without autism

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Toddlers with ASD show typical social orienting and positive facial expressions in response to predictable social stimuli.

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Variable social stimuli provoke an atypical pattern of reward-seeking behaviour in toddlers with ASD.

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Simulated social interaction, made possible by gaze-contingent eye-tracking, shows great potential to probe the conditions under which impaired social interaction emerges in ASD.

Several accounts have been proposed to explain difficulties with social interaction in autism spectrum disorder (ASD), amongst which atypical social orienting, decreased social motivation or difficulties with understanding the regularities driving social interaction. This study uses gaze-contingent eye-tracking to tease apart these accounts by measuring reward related behaviours in response to different social videos. Toddlers at high or low familial risk for ASD took part in this study at age 2 and were categorised at age 3 as low risk controls (LR), high-risk with no ASD diagnosis (HR-no ASD), or with a diagnosis of ASD (HR-ASD). When the on-demand social interaction was predictable, all groups, including the HR-ASD group, looked longer and smiled more towards a person greeting them compared to a mechanical Toy (Condition 1) and also smiled more towards a communicative over a non-communicative person (Condition 2). However, all groups, except the HR-ASD group, selectively oriented towards a person addressing the child in different ways over an invariant social interaction (Condition 3). These findings suggest that social interaction is intrinsically rewarding for individuals with ASD, but the extent to which it is sought may be modulated by the specific variability of naturalistic social interaction.