Face Processing and Autism at Multiple Stages of Life

    When talking about autism, the conversation is mainly dominated by thoughts about behaviors associated with autism. These behaviors include many stereotypes, such as making less eye contact, decreased sociability, and problems with reading social cues to name a few. Many studies concerning autism look into these associated traits to try to find a cognitive difference to better help kids and adults with autism. Research like this can help people get diagnosed earlier in life and get support for their needs in a world that can be difficult without it. 

    In "Cortical Source Analysis of the Face Sensitive N290 ERP Component in Infants at High Risk for Autism" by M. W. Guy, et al., the researchers aimed to find evidence linking the connecting between different N290 event-related potential (ERP) components in infants that have siblings with diagnosed autism (ASIB) and infants diagnosed with Fragile-X syndrome (FXS) which has links to autism. The rates for a later autism diagnosis in these groups are 20% and 60% respectively due to their previous studies. There was also the control group labeled as Low-Risk control (LRC) the ERP component N290 is thought to be a precursor to the adult N170 and has shown relations to face-processing differences in infants. The study uses Cortical source analysis, electrophysiological data measured on the scalp combined with a model of the head of the infant, to study the neural sources of this face-processing ERP. Obtaining these head models from the infant from MRI scans allows an easier approach to obtaining the data than with typical fMRI and EEG studies. Overall they found that all groups had greater responses to faces than toys and that the FXS group showed the greatest difference between toys and faces. FXS also showed a preference for familiar stimuli rather than unfamiliar ones, which was not present for either the ASIB or LRC groups. For the different head models, the Self (real infant head models) and the Infant Brain Imaging Study (IBIS), or group-specific MRI scans were used in times when Self caps were unable to be used. Each type was analyzed over different regions of interest (ROI). Overall, they found that both the Self and IBIS models could accurately show the processing differences between toys and faces. Using this ERP component data and the accuracy of the head models, this kind of testing could potentially diagnose children with autism as early as 12 months old, especially those who fall into the ASIB and FXS categories. 

    In "Face processing in young adults with autism and ADHD: An event related potentials study" by U. Aydin, et al., they aimed to help see the effects of autism and ADHD diagnosis in early adults using the same mechanism of studying face-processing ERP components but using the adult N170 ERP. Though a meta-analysis of many studies showed a small to non-significant difference between autistic adults and non-autistic adults, there is still shown that there is a sensitivity to the N170 ERP in autistic adults comparatively. For their study, they uses EGG technology to obtain information during the ERP tasks. The adults were put through two passive-viewing tasks, one showing upright and inverted faces with either direct or adverted gaze and a second task with faces expressing different emotions. Results showed that there were in fact differences in latency among those with autism- (without autism diagnosis) and those with autism+ (with autism diagnosis) along with differences between sexes as well. Overall, inverted faces had longer latency than upright faces, and "negative" emotions such as disgust, anger, and fear had longer latency than joy or neutral expressions for all groups. The N170 amplitude, autism- had higher amplitudes than those with autism, but the opposite was found for the N170 latency, with the same pattern showing with ADHD+ individuals. 

    Using these two studies, there is a clear difference between individuals with and without an autism diagnosis. Using technology to study ERP components in infants, children, and adults can be an accurate way to diagnose and study the effects of autism in relation to social behavior. If infants are diagnosed earlier due to this technology there can be more resources allocated to them. With studies in adults, we can see the effects of face-processing differences related to behavior such as why eye contact tends to be harder to maintain in older individuals with diagnosed autism. Hopefully, research like this can help people to better understand peers and people that have autism. 

References

Guy, Maggie W., et al. “Cortical Source Analysis of the Face Sensitive N290 ERP Component in

    Infants at High Risk for Autism.” Brain Sciences, vol. 12, no. 9, 2022, p. 1129.,

    https://doi.org/10.3390/brainsci12091129. 

Aydin Ü, Cañigueral R, Tye C and McLoughlin G (2023) "Face processing in young adults with autism     and ADHD: An event related potentials study. Front. Psychiatry" 14:1080681. doi:    

    10.3389/fpsyt.2023.1080681