Oxytocin is the hormone that promotes social bonding, so it makes sense that defects in oxytocin might play a role in some cases of autism. Karen Parker is exploring whether changes in oxytocin levels in the blood or cerebrospinal fluid could be a marker of the disorder. "My work is thinking about the biology of social functioning," says Parker, an assistant professor of psychiatry and behavioral sciences. Oxytocin is sometimes called the cuddle hormone or the love hormone, because it's released during physical contact and sex; it also plays a role in social interaction, trust and empathy, as well as monogamy in certain animals. Parker studied the role of oxytocin in voles and monkeys before moving to autism research.
Parker has collected blood from children with autism, their healthy siblings (who sometimes show more subtle social deficits) and normal controls to try to detect differences in their oxytocin levels. She also is setting up one of the first studies in the cerebrospinal fluid (CSF). Studies in monkeys show that blood oxytocin may be normal even when brain levels, reflected in the CSF, are low. It's difficult to obtain CSF because it requires a spinal tap. Her team is investigating genetic variation in the oxytocin receptor and other genes involved in the oxytocin pathway. If Parker's and Hardan's studies show an oxytocin deficiency, patients could receive replacement oxytocin.
It's promising research because low oxytocin is treatable, Parker says. In a recent study, when 13 autistic adults were given an oxytocin nasal spray (which delivers the drug straight to the brain), they had significant improvements in reading social cues and in making eye contact. "I think it's actually fascinating that you can apply oxytocin once and see these pretty acute social changes," Parker says. "Oxytocin is the only drug that's been shown to alter social functioning. There's nothing else that touches the social deficits."
