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October 2007
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Gray and White Matters

There seems to be a flood of brain research lately that helps illuminate how the brain responds to social stimuli.

An intriguing new area is looking at two kinds of tissue in the brain: white matter and gray matter.  We usually think of gray matter as the stuff we use for cognition; more grey matter tends to equal a higher IQ, for example. White matter, on the other hand, is the connective nerve tissue thought to be used for "wiring together" different parts of the brain.

Of course, it's not that simple.  Too much gray matter in some regions has been linked to trauma.

Two studies released today looked at the relationship between volume of white or gray matter and behavior.

First, a team led by Manzar Ashtari of the Children's Hospital of Philadelphia in Pennsylvania looked at the brains of autistic kids. They found more gray matter than normal in parts of the brain dealing with social interactions. They think this could be related to abnormal function of the mirror neuron system.

Mirror neurons are thought to be special kinds of nerve cells that fire when we watch others. It's still speculative in humans, but they've found that monkeys have what they call mirror neuron regions that fire when the monkey watches a researcher pick up a cup. This might be related to empathy, the ability to literally put oneself in another's place. See Mirror Neurons, Oxytocin and Autism for more.

According to the Science Daily story,

"In the normal brain, larger amounts of gray matter are associated with higher IQs," Dr. Ashtari said. "But in the autistic brain, increased gray matter does not correspond to IQ, because this gray matter is not functioning properly."The autistic children also evidenced a significant decrease of gray matter in the right amygdala region that correlated with severity of social impairment. Children with lower gray matter volumes in this area of the brain had lower scores on reciprocity and social interaction measures.

Another study by James Cantor of the Centre for Addiction and Mental Health in Toronto  found significantly less white matter in the brains of pedophiles than in the brains of non-sexual offenders. The article says,

The study, published in the Journal of Psychiatry Research, challenges the commonly held belief that pedophilia is brought on by childhood trauma or abuse. This finding is the strongest evidence yet that pedophilia is instead the result of a problem in brain development.

I don't understand why they draw this conclusion. Plenty of studies have shown abnormalities in brain development in children who've been neglected, abused or traumatized. In fact, Victor Carrion of Stanford has found more gray matter in the prefrontal cortexes of the brains of children with PTSD. He's also found decreased total volume in the PFCs of adults and children with PTSD.

He recently told me that it's difficult to identify exactly what these differences mean when it comes to brain function and behavior. He said, "It seems like in some regions, there's a problem if you have more volume ...  in others, it's problematic if you don't have enough."

It seems to me that Cantor's study provides further evidence for two things: that early trauma affects brain development, and that this abnormal brain development leads to abnormal behavior later.

I've contacted the Centre for Addiction and Mental Health to more information on this statement. I'll post if and when they get back to me.


Retraining the RAD Brain

I published a story today in the East Bay Express, called When Love Is Not Enough.

The story uses the experiences of two local families who adopted children from overseas to discuss some of the therapies being used to retrain the brains of kids with attachment disorder, PTSD and other abnormalities of brain development.

I didn't get into the oxytocin response too much -- it's too complicated and not the focus of the story. But you can look at the therapies discussed -- attachment therapy, neurofeedback and neurodevelopmental reprogramming -- as ways of building the oxytocin response in the brain.

Gee, Your Hair Smells ... mmmm ...

There's an oxytocin spray out there that promises that if you spray it on yourself, others will trust you and like you more.

This fantasy has an earlier history in the pheromone product craze. Now, it's actually a bit more likely that spraying pheromones on yourself could work. The problem is, science hasn't identified any human pheromones. Probably because they're not looking.

Pretty much everyone else in the animal kingdom responds to pheromones of all kinds. In mammals, the primary site is the vomeronasal organ, a region of tissue in the nostril that can take in molecules. Until very recently, scientists believed that, while human fetuses had a vomeronasal organ, it was an evolutionary throwback that disappeared by birth. Ha ha. It definitely persists after birth.

Multiple experiments have found that humans are indeed able to detect molecules of testosterone, estrogen and other such in sweat and saliva.

Which is a long way around to a product I happened upon while trying to find my favorite hair conditioner.


Got2B Magnetik claims to be (and is, no doubt) the first hair product to contain pheromones. I really love the way they mince words in their claim:

Pheromones are clinically proven to positively influence the psychology of attraction.

Okay, whatever.

BTW, you have to say you're 18 to enter the site. Pretty smart marketing!

For more on the vomeronasal organ, see Smith, Timothy D. and Bhatnagar, Kunwar P., The human vomeronasal organ. Part II: prenatal development Journal of Anatomy (2000), 197: 421-436

Are You Addicted to Love?

Not a quiz, but a fun and funny piece from Ireland about love addiction. In That Crazy Little Thing Called Love, Caitriona Durcan writes about the obsessive stage, better called romantic love -- and how it can make you act really crazy.

From the article:

"Once the love bug bites, serotonin levels in the brain drop, triggering obsessive behaviour," says behavioural psychologist Ciaran Foley. "The neural circuits controlling social judgment are suppressed and stress hormones increase, leading to higher blood pressure and sleep loss."
As usual, the article doesn't differentiate between the crazy romantic love and the calm and connected true love. It's the latter that's based on oxytocin.

So remember, everyone. When the madness fades, you haven't fallen out of love. You've just fallen into a new kind.

Quiz: Bidding for Connection

In a comment, Adam Khan, author of Self-Help Stuff that Works and the MoodRaiser blog, pointed me to the work of John Gottman, a University of Washington psychologist who studies how couples interact.

As a psychologist, Gottman studies behavior, not neurochemistry or brain function. But he has an interesting concept called "bidding for connection." His idea is, we constantly make attempts to connect with others via words, looks, actions, etc. In a good relationship, our bids are answered regularly.

You could look at Gottman's bids as attempts to enter into oxytocin-producing exchanges.

At any rate, on the Gottman Institute website are several fun quizzes, including a quiz that helps you understand the way you tend to bid for connection.

Social Support at Work

Warm interactions with others can be a reliable source of everyday oxytocin, as long as we're able to trust and open up.

According to the New York Times, a new study shows that friendships at work can protect against burnout and depression.

Many of us avoid getting close to co-workers, or even socializing with them or getting personal. It's unprofessional, we fear, and could lead to embarrassing entanglements. Some of us like to maintain a different persona for work that hides or minimizes interests or traits we feel aren't mainstream or widely acceptable.

However, according to the article,

People who said they felt generally supported by their colleagues and could lean on co-workers in a time of crisis were spared the rigors of job stress. In the study, men and women who felt little social support at work were two to three times more likely to suffer major bouts of depression.

Certainly, those of us who don't get close and personal with co-workers lose the opportunity to engage in a stress-reducing oxytocin response with them.

The study: Major Depressive Episodes and Work Stress: Results From a National Population Survey

Validation for "Tend and Befriend"

In 2000, Shelly Taylor, a social psychologist at UCLA proposed an alternative model to the well-known fight-or-flight response.

Based on an analysis of a wide range of research by others, Taylor hypothesized that women faced with threat might have evolved a different response, something she called "tend and befriend." The idea is that females in ancient times had to protect the children while the men fought off the danger. So, they gathered together in groups to defend the youngsters.

This tendency would likely be influenced by oxytocin, the neurochemical that, among other things, drives us to connect with others. Sue Carter of the University of Illinois,  has done work with prairie voles showing that when they're isolated and stressed, their oxytocin levels rise. She thinks this causes them to seek out others -- in human terms, you could say, for support.

Many have pooh-poohed Taylor's ideas, possibly because she's a psychologist, not a neuroscientist, possibly because she's a woman.

But now, researchers at the University of Pennsylvania have done a brain imaging study that supports her hypothesis.

In the study led by J.J. Wang, men  and women were stressed by being asked to do arithmetic in front of a panel of strangers who constantly asked them to go faster or start over if they made a mistake. According to Science Daily:

The researchers measured heart rate, cortisol levels (a stress hormone), subjects' perceived stress levels throughout the experiments, and regional cerebral blood flow (CBF), which provides a marker of regional brain function. In men, it was found that stress was associated with increased CBF in the right prefrontal cortex and CBF reduction in the left orbitofrontal cortex. In women, the limbic system -- a part of the brain primarily involved in emotion -- was activated when they were under stress.

In other words, under stress, the men got busy thinking harder, while the women  increased their emotional activity. The hypothalamus, producer of oxytocin, is part of the limbic system. It's possible that these women's brains secreted extra oxytocin, which may have calmed them.

Taylor, S.E., Klein, L.C., Lewis, B.P., Gruenewald, T.L., Gurung, R.A.R., & Updegraff, J.A. (2000).  Biobehavioral responses to stress in females: Tend-and-befriend, not fight-or-flight.  Psychological Review,107, 411-429.

Better Than Human

If you could control your emotions with pills, what would you choose to do?

Most people would likely ask for a pill that made them happier and gave them more love in their lives. The intense interest in oxytocin as a drug comes, I think, from feelings of loneliness and disconnection that many of us have.

If that's so, we would probably use oxytocin drugs to connect more deeply with others. That's the premise of a paper by J. Hughes, executive director of the Institute for Ethics and Emerging Technologies. In "Virtue Engineering: Applications of Neurotechnology to Improve Moral Behavior," he disagrees with those who fear that psychoactive pharmaceuticals will make us self-absorbed emotional zombies.

He says, "Contrary to the bioconservative accusation that neurological self-determination and human enhancement will encourage more selfishness in society, it will probably permit people to be even more moral and responsible than they currently are."

The transhumanist ideal is to be able to reshape ourselves to be better humans, not worse ones, Hughes explains. For example, just a you might use a nicotine patch to help you stop smoking if willpower isn't enough, you could use a patch that would help you keep homophobic impulses to yourself.

Besides, there's evidence that endogenous oxytocin can help us learn new responses that become permanent without continual dosing. In Eric Hollander and Jennifer Bartz's experiments giving oxytocin to autistic adults, they were better able to identify the emotional tone of language not only while they were under the effects of the drug, but for weeks afterward. (For more on this, see Oxytocin Therapy for Autism Gets Closer.)

Because the brain can form new connections throughout our life, practicing connection and love while under the influence of oxytocin could help us learn how to do it every day, forever.

Understanding the Brain's Wiring

In the past 15 years or so, science has delved into the structure of the brain, identifying areas and figuring out what they do with PET, MRI, CAT and fMRI scans. Our understanding has gone from Paul MacLean's division into the "triune brain" -- reptilian brain, limbic system and neocortex -- to distinctions like the anterior commissure and the cingulate gyrus.

Today, psychologists still use metaphors to discuss how the brain works: the social brain, the reward center, the dopamine pathway. They're getting closer to understand how the brain is organized, but metaphor and hypothesis are still central.

According to Technology Review, the field of connectomics could soon provide a map of every connection in the brain. According to the story:

Denk, Seung, and their collaborators are now developing sensitive new imaging techniques and machine-learning algorithms to automate the construction process. They have already generated a partial wiring diagram of part of the rabbit retina. But they'll need to make their technique a million times faster to finally bring larger maps--like that of a cortical column--into the realm of reality.

If they pulled this off, it would help psychiatrists treating kids whose brain development has been thwarted or twisted by early neglect or abuse. They could actually understand "the oxytocin system," for example, and determine whether therapy was rebuilding the oxytocin response.

Do You Have Empathy? Quiz

  800.000 votes of confidence... 
  Originally uploaded by carf.

Oxytocin has been shown to increase empathy. Well, what exactly is empathy?

In one study, men who inhaled oxytocin saw photos of faces as less threatening than the control group. In another study, they were better able to infer someone's emotional state based on a photograph showing only the people's eyes after inhaling oxytocin.

Those scientists gave their paper the sexy name, "Oxytocin Improves 'Mind-Reading' in Humans." It's not so easy to measure empathy -- and whether one person has empathy for the other has been the basis of millions of relationship fights. The researchers used a test devised by Simon Baron-Cohen (yes, those Baron-Cohens), a professor of developmental psychopathology at Cambridge University.

For more about the study, read my post, "Insight into Insight." But here's what's fun. You can take the test right now.

Thanks to Adam for the link to the "Reading the Mind in the Eyes" test.