Oxytocin promotes function of face-recognition brain centers
The ‘Bonding Hormone’ That Might Cure Autism
A scientist explains his fascinating research. Then we explain his explanation.
By Mary Carmichael | Newsweek Web Exclusive
Feb 26, 2010
News about autism is almost always controversial, but the latest report that has people abuzz—about researchers who have successfully treated some symptoms of the disorder using a nasal spray of oxytocin—shouldn't come as much of a shock. Scientists have been experimenting with oxytocin as an autism treatment for years. In the new study, conducted by French researchers, 13 subjects with "high-functioning autism" (a.k.a. Asperger syndrome) became more trusting and socially engaged under the hormone's influence. It's a small study, but it has big implications, and it tracks with findings from other researchers. Mary Carmichael spoke with one of those scientists, Eric Hollander, who is the director of the compulsive, impulsive, and autism spectrum disorders program at the Montefiore Medical Center in New York. Excerpts below, with our easier-to-understand translation:
What is the oxytocin spray actually doing in the brains of these patients?
Hollander: In patients with autism, the fusiform gyrus doesn't seem to light up in response to human faces. They light up an adjacent region called the inferior temporal gyrus, which normally gets lit up when people are looking at man-made objects. But we seem to get more recruitment of the fusiform gyrus when we administer oxytocin.
This means: Unlike a healthy brain, an autistic one may not recognize human faces as something special—it puts them in the same category as regular objects. By boosting levels of oxytocin, researchers may be able to fix that problem, causing the autistic brain to respond to faces in a more normal way.
Hollander: We've seen effects in another region, called Brodmann Area 25, which is very active in individuals who have treatment-resistant depression. High-functioning adults with autism also have a very active Area 25, and in response to the oxytocin, there's a big reduction in activity.
This means: Oxytocin tamps down activity in a part of the brain that's linked to depression and stress. "Area 25" activates the "fight-or-flight response." If it malfunctions and starts firing all the time, it causes people to feel chronically stressed out. By calming down the activity in Area 25, oxytocin also calms down patients.
Do people with autism have abnormally low levels of oxytocin?
Hollander: It's challenging to measure the blood-plasma levels of oxytocin—it can be released in blips throughout the day, so it varies—but studies in children have found abnormalities in the plasma levels, and the subgroup of children with autism who are the most socially aloof tend to have the lowest levels of oxytocin. There are also studies in monkeys that have measured oxytocin levels in the spinal fluid as well as in the plasma. These studies show if you inhibit nurturing behaviors early in life, the spinal fluid and plasma levels of oxytocin are low, and they stay low throughout life.
This means: The data isn't perfect, but children with autism, especially severe cases, seem to have low oxytocin levels. Primate research, which is in some ways more rigorous, has shown that monkeys deprived of maternal love as infants tend to have chronically low levels of oxytocin throughout their lives.
Monkeys deprived of love have low oxytocin levels, and so do kids with autism? Doesn't that sound an awful lot like the discredited “refrigerator mother” hypothesis?
Hollander: In extreme cases of maternal deprivation, like children raised in orphanages without any early maternal behavior, there can be a long-lasting effect on oxytocin that's associated with social deficits. However, that probably is not the case with good or bad mothering. These are extreme cases of total lack of nurturing. [Where is Hollander's evidence for this statement about good or bad mothering?]
This means: This research does not mean that autism can be blamed on bad parents. The only time there might be links between parenting, oxytocin, and autismlike behavioral problems is in cases when a child has had no meaningful interaction with caregivers whatsoever. [Note the spin applied here by the reporter - to protect the feelings of parents, no matter what]
Some behavioral therapies seem to help people with autism, especially if they're delivered early in life. Is it possible that these therapies work by increasing oxytocin levels?
Hollander: Those therapies are really important—that's the whole point of diagnosing autism early, because the therapies can really improve the long-term developmental trajectory—but nobody has specifically measured oxytocin in response to them. I can tell you that there are things we know of that can enhance oxytocin levels. Deep pressure massage does it, and breast-feeding, and sexual intercourse. We also know that patients with autism tend to calm down by doing certain physical activities, like lying underneath a mattress or using Temple Grandin's squeeze machine."