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Autism and Environmental Factors, First Edition. Omar Bagasra and Cherilyn Heggen.
© 2018 John Wiley & Sons, Inc. Published 2018 by John Wiley & Sons, Inc.
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How could intelligent beings seek to control a few unwanted species by a
method that contaminated the entire environment and brought the threat
of disease and death even to their own kind?
Rachel Carson, 1962, Silent Spring
Oxytocin
The neuropeptide oxytocin and its receptor have been predicted to be involved
in the regulation of social functioning in autism spectrum disorders (ASDs).
Produced in the hypothalamus, oxytocin is a neurotransmitter involved in
social behaviors, including mammalian labor and nursing, maternal behavior,
bonding, and social recognition and reward [1]. It binds to oxytocin receptors
expressed by neurons across the brain, including in the amygdala, olfactory
bulb, nucleus accumbens, brainstem, septum, and ventromedial hypothalamus [2].
Studies of mice in which the oxytocin receptor gene has been deleted revealed
deficits in social interaction, including spending more time alone and self‐
grooming, compared with their wild‐type counterparts [3–5]. These behaviors
are similar to those of individuals with ASD, suggesting that alterations in the
oxytocin receptor during fetal development may help explain some of the
social deficits characteristic of individuals with ASD [6–17]. In fact, decreased
flow of oxytocin between mother and fetus has been associated with autistic‐
like characteristics in adulthood [6].
Autistic‐like behavior is observed when the receptor for oxytocin is down‐
regulated, thereby reducing binding of oxytocin in the central nervous system,
resulting in social interaction deficiencies that are a hallmark of ASD [8–10].
Low levels of plasma oxytocin are associated with lower social and cognitive
functioning [18–28].
4 Oxytocin, Arginine Vasopressin and Autism Spectrum Disorder
Spectrum Disorder
