Individuals with autism spectrum disorder (ASD) often find it difficult to look others in the eyes, and we don’t exactly know why. What could be granted for indifference could actually have a completely different explanation.
Indeed, according to Nouchine Hadjikhani, cofounder of Neurochlore and director of the Neurolimbic Research Laboratory in the Martinos Center in Harvard, who conducted this new study, the results show that “this behavior is a way to decrease an unpleasant excessive arousal stemming from overactivation in a particular part of the brain.”
Using functional magnetic resonance imaging, Pr. Hadjikhani’s team measured differences in brain activation when people with or without ASD were forced to focus around the eye region. They showed that the subcortical pathway, which consists of superior colliculus, pulvinar nucleus of the thalamus and amygdala and which enables rapid and automatic face processing, was more active in participants with ASD.
This result supports the hypothesis of an imbalance between the brain’s excitatory and inhibitory signalling network in autism. This imbalance could lead to a strengthen excitatory signalling in the subcortical circuitry involved in face perception, which in turn would result in an abnormal reaction to eye contact and thus an aversion to direct gaze.
Beyond the better understanding of the mechanisms of these disorders, these results will enable to improve the care of the patients: forcing children to support someone else’s gaze could create anxiety, while a slower habituation could allow them to overcome this overreaction.
Nouchine Hadjikhani graduated from Medical School in Lausanne, Switzerland, in 1995. After a first post-doctoral fellowship at the Karolinska Institute (Sweden), she started her career at the Harvard Medical School, in Boston. She is currently Associate Professor in Radiology. She is also Director of the Neurolimbic Research Laboratory in Martinos Center for Biomedical Imaging (Boston), as well as Invited Professor at the Gillberg Neuropsychiatry Center in Gothenburg (Sweden). Last, she directed a lab at the Swiss Federal Institute of Technology (EPFL) during 6 years.
More informations :
Article : Nouchine Hadjikhani, Jakob Åsberg Johnels, Nicole R. Zürcher, Amandine Lassalle, Quentin Guillon, Loyse Hippolyte, Eva Billstedt, Noreen Ward, Eric Lemonnier, Christopher Gillberg. Look me in the eyes: constraining gaze in the eye-region provokes abnormally high subcortical activation in autism. Scientific Reports, 2017; 7 (1) DOI: 10.1038/s41598-017-03378-5
Nouchine Hadjikhani’s lab website : http://nmr.mgh.harvard.edu/nouchinelab
