Oxytocin may enhance social awareness in autism

Larry Young

Known as the “cuddle hormone” and “love hormone,” oxytocin is associated with warm feelings and social bonds. Indeed, oxytocin plays a key role in establishing one of the most primal and important relationships: that between mother and child. The hormone is involved in the progression of labor, the nurturing act of breast-feeding and the focusing of maternal attention on an infant.

“Oxytocin is released within the brain at the same time a woman is giving birth, at the same time she is nursing, and it transforms her brain so that baby becomes the most special thing in the environment,” Larry J. Young, PhD, professor of psychiatry, director of the Center for Translational Social Neuroscience and director of the Silvio O. Conte Center for Oxytocin and Social Cognition at Emory University, told Endocrine Today. “It increases the salience of that baby’s cues. That’s the quintessential role, the original role, of oxytocin that happens in all mammals: focusing the attention of the brain on social cues.”

Given its powerful role in the science of attachment and the processing of social stimuli, oxytocin has been explored for use in several psychiatric conditions. Young spoke with Endocrine Today about the potential for use of oxytocin in treating patients with autism, schizophrenia and social anxiety, and its use in combination with behavioral therapy.

What is the “ social brain ” and what role does oxytocin play in it ?
Young: The social brain is a metaphor that refers to the part of the brain that processes social information differently than other information. The social brain is a series of circuits that flow social information through the brain to areas that are involved in attention and reward, for example. We know that oxytocin plays a role in attention to and reward of social information, causing a baby to become very important to the mother, for example. From that, we’ve learned that oxytocin is involved in other kinds of social processes, too.

In mice, for example, oxytocin is needed for a mouse to recognize another mouse. Mice remember each other by their smell. The brain has to focus attention to form a memory, and oxytocin is what makes that happen. Without oxytocin, a mouse will never remember another mouse it has met before.

It’s similar with people. Every person has eyes in the same place, the nose in the same place, the mouth in the same place, but we recognize very minute differences in each other’s faces. That’s what oxytocin does; it makes us pay attention to subtle social detail.

The animals I studied, prairie voles, form strong bonds. Once a male and a female pair up, that partner is very rewarding to them and they want to be with that partner. This also involves oxytocin. In terms of pair bonding, oxytocin enhances the signal of the partner, allowing it to reach the reward center of the brain essential for linking the neural encoding of the partner to reward.

How does this relate to autism?
Young: Children with autism have difficulty in interpreting emotions in others. The idea is that oxytocin could enhance their attention to the social information around them. One of the deficits in autism is that social information is not that salient to these patients; they’re not drawn to someone’s eyes like most of us are drawn to the eyes. Some studies have shown that they have difficulty recognizing faces, they have difficulty interpreting emotions in others. The idea is that oxytocin will enhance their attention to the social information around them, helping them to navigate in the social world.

In acute studies, researchers have given oxytocin to patients with autism and evaluated whether it helps them read emotions better. However, the effect is very short — an hour later, the oxytocin is gone. In studies on chronic use, oxytocin is given every morning and evening. The problem with that is, if you give a child oxytocin before you send them off to school, it may intensify the experience of negative social stimuli. Kids can be mean; kids bully. So, we’ve suddenly turned up the ability of these kids’ brains to pay attention to others around them, and that might not be a positive experience. That’s the mistake of the recent trials that have been done. If you view oxytocin as enhancing the salience of social stimuli, then you want to control those social stimuli.

In my opinion, the most effective way to use oxytocin would be in combination with behavioral therapy. Autistic kids who go to behavioral therapy are taught social skills. It’s reward-based learning, but they might not be as attentive to the therapist as they could be. If suddenly you harness the power of oxytocin to significantly increase their social awareness during this therapy session, perhaps that therapy session will be even more effective. Even without oxytocin, behavioral therapy does work; it helps kids a lot. But if we can use oxytocin to enhance the efficacy of that behavioral therapy, maybe that will produce a long-term effect.

What is the specific mechanism in the brain that causes autism?
Autism is complicated because there are many different genes implicated in the condition. Autism is a problem with neuro-communication. Neurons don’t communicate with each other as well as those of a typically developing person. A social encounter is a dynamic process. You look at someone’s face and they’re showing expressions; you have to interpret what’s being communicated quickly. The autistic brain isn’t capable of dynamically integrating information across different brain areas to get a wholistic view of that social situation.

It’s not that these kids don’t have enough oxytocin; there are a lot of reasons that prevent the brain from being able to communicate effectively across different brain areas. However, in a normal brain, oxytocin maximizes the communication between brain areas and the flow of information. So, if you can work around that defect using this oxytocin system, it might improve the way these children can process social information. Oxytocin doesn’t have much to do with the cause of autism, but it is possibly a way of amping up the social brain so that these children can deal with social information better.

What other psychiatric conditions might oxytocin be useful in treating?
Young: Oxytocin is being studied for schizophrenia. This might be for a patient who is taking antipsychotic medications and so is no longer having delusions but is still avoidant of other people. Social anxiety is another potential use, because in addition to heightening sensitivity to social information, oxytocin as an anxiolytic effect.

Studies are ongoing on these uses. However, I don’t know that these studies are going on in the way they should be, which is in combination with behavioral therapy. Unfortunately, it takes so long to get funding for clinical trials and prepare; the ones being published now are not conceived in a way based on the current science, but are from 5 or 10 years ago, when people thought oxytocin was just a prosocial molecule. Currently, we’re probably in our second generation of studies. The first ones involved giving a single dose and seeing what happened. Now, there are studies where patients are given a dose in the morning when they wake up, and then in the evening. Those, I think, are going to be somewhat inconclusive because they lack the behavioral therapy component.

What do you think future studies of oxytocin will be like?

Young: The next generation will involve two things. One is combining oxytocin with behavioral therapy. The second is going beyond giving the patient the molecular oxytocin itself, but instead giving another drug, one that enhances oxytocin signaling in the brain.

This is similar to antidepressants; look at the selective serotonin reuptake inhibitors, or SSRIs. We don’t actually give serotonin to people with depression. None of the other drugs we give patients are the same molecules that are in the brain. We give drugs like SSRIs, which enhance the serotonin in the brain. The problem with giving oxytocin is that not much gets into the brain. The future likely will focus on something that might boost the brain’s own oxytocin. We need to go beyond just giving oxytocin to thinking of other chemical routes of manipulating the oxytocin system. – by Jennifer Byrne

For more information:

Larry J. Young, PhD, can be reached at 954 Gatewood Road, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329; email: lyoun03@emory.edu.

Disclosure: Young reports no relevant financial disclosures.