It’s 8:00 AM at the APA annual meeting in Toronto. I have a bit of down time between the breakfast symposium I just ducked out of and a 9:00 symposium. Some quick thoughts off the top of my head:
The amygdala is emerging as the star of the conference. This is a tiny part of the brain, way down deep in the primitive layer, associated with response to negative stimuli. A landmark imaging study has found that subjects with a certain variation in a particular gene have a more pronounced reaction in the amygdala. In healthy subjects, the higher areas of the brain work to extinguish this arousal. A recent study, however, has found that those with the same gene variation (known as the short allele to the serotonin transporter gene) experience disruptions to the circuitry. So the amygdala stays fired up, and that’s not good.
What happens? Yet another landmark study has found that those with the short allele who have been exposed to various forms of stress (such as financial worries) tend to suffer a lot more from depression and anxiety.
So here’s the deal: We don’t have “depression” genes or “bipolar” genes. We have genes that code for particular functions in the cell. These cells in turn organize into systems in the brain. These systems, in turn, influence how we behave. So what happens if you find out you’re one of the unlucky ones born with the short allele? Well, there are thousands of other genes expressed in the brain and countless other brain systems which can have a moderating influence on your over-sensitive amygdala. So you may be able to breathe easy.
Also, there is at least one study showing that cognitive behavioral therapy can cool down the amygdala. Antidepressants may also help.
This little example illustrates a theme emerging from this conference: Namely that biology, environment, mood and behavior all intersect. Neither can be looked at in a vacuum.
Speaking of behavior, I’ve been attending various sessions that explore the topic. Psychiatry tends to ghettoize what they call “personality disorders” into “Axis Two” disorders, as if to indicate a lesser level of importance than “Axis One” disorders such as bipolar disorder. But what happens if our temperament affects how we respond to our meds? What if our various personality traits complicate the course of our illness?
The unfortunate answer is we don’t really know.
Now let’s link Axis Two to biology. We’re no more likely to find personality genes than mood genes, but we are hot on the trail for genes that predispose certain individuals to impulsivity and neuroticism. Suppose a psychiatrist had a full inventory of our genes and personality traits? Wouldn’t that inform him or her regarding treatments? So instead of a pill lottery we have a much better chance of getting put on a med that is likely to work for us.
The bad news is psychiatry has a long way to go. The good news is they’re working on it.
This is John McManamy, “live” from the APA annual meeting in Toronto …
Tell us what you think of these latest findings in the message boards.
Published On: May 24, 2006
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