genes and depression
Folks in psychology right now are flipping their lids over 5HTTLPR, the serotonin transport gene. It codes for serotonin transport proteins in the brain, and is strongly linked to depression. Strongly. People who have two copies of the short (less active) allele are much more likely to become depressed than others. What's more, they show cognitive risk factors for depression even if they've never been depressed, like increased subliminal attention to angry faces and a sympathetic nervous system that keeps pumping out stress hormones even after whatever was stressing them is gone.
These factors by themselves don't make you get depressed. What they do is rob you of resilience. People with the long/long or the long/short genotype can go through some "life events" (a broad category that can range from buying a house to becoming a refugee from genocide) and get back to normal after a couple of months. People with the short/short genotype are much more likely to go into massive overstress, leading to mental and physical collapse: Depression. Worse yet, every episode of depression lowers your threshold for a future episode*, so even if it took a terrorist attack to set off your first episode, your fifth episode could be set off by getting an A- in a class.
* There are too many theories as to why this is. Rehearsal of negative cognitions? Self-fulfilling prophesies about negative emotions? Hippocampal atrophy? Stress system kindling? Erosion of structures for social support and enjoyable activities? Bodily damage due to prolonged stress hormone overload? It's not answered.
At APS, Shelly Taylor showed us some of her work on 5HTPR. Her graph was the same as the other ten people who had presented on it that weekend:
Long/long people generally roll with the punches and don't end up permanently impaired no matter how much bad stuff happens to them. Short/short people are fine as long as their lives are calm, but they don't deal well at all with adversity.
But, she said, what happens if we extend the graph to the left? (Shelly Taylor is one of those people who does bang-up positive psychology work without ever using that name). This is what you get if you separate out people who have no trauma, and also a lot of good supportive features:
The lines flip! Those poor short/short people actually do better than their tougher peers.
I didn't catch why Taylor said this might be the case, if she said so. euziere thinks it might be because people do better if they're responsive to the ups and downs in their environment. People who are neurochemically prepared to weather earthquakes and famines might not be the most sensitive to small social nuances and everyday difficulties. In this view the short/short genotype is like listening to a quiet instrumental piece with your earphones turned way up. You'll hear more than someone who has the volume lower -- but if there's a sudden cymbal crash in the middle, your head's going to explode. Or again, perhaps a long/long person in a very placid, unthreatening environment has much equanimity -- a little bit like when someone is taking too high a dose of SSRIs and gets kind of zombified and emotionally flat.
This clearly isn't the entire story. We need to understand more about what protects vulnerable people from becoming depressed, to what extent they can actually avoid all risky stressors, and how resilience can work as a learned skill rather than a general emotional blunting (which we already know a little about). And there are definitely social and functional benefits to being optimistic and resilient even when times are good. But I thought this finding was amazing and certainly a reversal of how we usually look at things.
These factors by themselves don't make you get depressed. What they do is rob you of resilience. People with the long/long or the long/short genotype can go through some "life events" (a broad category that can range from buying a house to becoming a refugee from genocide) and get back to normal after a couple of months. People with the short/short genotype are much more likely to go into massive overstress, leading to mental and physical collapse: Depression. Worse yet, every episode of depression lowers your threshold for a future episode*, so even if it took a terrorist attack to set off your first episode, your fifth episode could be set off by getting an A- in a class.
* There are too many theories as to why this is. Rehearsal of negative cognitions? Self-fulfilling prophesies about negative emotions? Hippocampal atrophy? Stress system kindling? Erosion of structures for social support and enjoyable activities? Bodily damage due to prolonged stress hormone overload? It's not answered.
At APS, Shelly Taylor showed us some of her work on 5HTPR. Her graph was the same as the other ten people who had presented on it that weekend:
Long/long people generally roll with the punches and don't end up permanently impaired no matter how much bad stuff happens to them. Short/short people are fine as long as their lives are calm, but they don't deal well at all with adversity.
But, she said, what happens if we extend the graph to the left? (Shelly Taylor is one of those people who does bang-up positive psychology work without ever using that name). This is what you get if you separate out people who have no trauma, and also a lot of good supportive features:
The lines flip! Those poor short/short people actually do better than their tougher peers.
I didn't catch why Taylor said this might be the case, if she said so. euziere thinks it might be because people do better if they're responsive to the ups and downs in their environment. People who are neurochemically prepared to weather earthquakes and famines might not be the most sensitive to small social nuances and everyday difficulties. In this view the short/short genotype is like listening to a quiet instrumental piece with your earphones turned way up. You'll hear more than someone who has the volume lower -- but if there's a sudden cymbal crash in the middle, your head's going to explode. Or again, perhaps a long/long person in a very placid, unthreatening environment has much equanimity -- a little bit like when someone is taking too high a dose of SSRIs and gets kind of zombified and emotionally flat.
This clearly isn't the entire story. We need to understand more about what protects vulnerable people from becoming depressed, to what extent they can actually avoid all risky stressors, and how resilience can work as a learned skill rather than a general emotional blunting (which we already know a little about). And there are definitely social and functional benefits to being optimistic and resilient even when times are good. But I thought this finding was amazing and certainly a reversal of how we usually look at things.