Depression and Brain Training
A recent article in the Proceedings of the National Academy of Sciences may give us a clue on why depression and mental abilities are linked. In the past, my colleagues and I looked at how depression can actually increase the risk for developing Alzheimer’s disease. The article in PNAS, authored by Aaron Heller, though, suggests that brain functioning itself may be affected by depression.
The study reported looked at how well depressed people could activate a part of the brain called the nucleus accumbens. The nucleus accumbens is a small area of the brain that lies deep inside it. It is mostly known as a center for the metabolic activity of reinforcement. Drugs that can be abused, such as cocaine, increase activation in that part of the brain. Activation in the nucleus accumbens is often thought to reflect positive feelings or pleasure.
The paper in PNAS showed that depressed patients weren’t able to keep the nucleus accumbens activated in response to something positive. It’s a little like when you talk to a friend who’s feeling sad. You may be able to cheer them up for a little while, but they may go back to feeling depressed pretty quickly.
The authors note that the results are suggestive, but not definitive, on the ways that depression can affect things such as motivation and psychomotor speed (the ability to think and do things quickly, like driving a car).. Reduced psychomotor speed is especially relevant because some influential researchers on how mental abilities change with age, such as Timothy Salthouse, have suggested that psychomotor speed may be a key to cognitive decline as we get older. The paper by Heller and his colleagues, suggested that difficulties in sustaining activation of the nucleus accumbens can reduce psychomotor speed.
The authors of the paper also note that interventions that can help people who are depressed maintain activation of the nucleus accumbens may be useful in treating depression. And that’s an interesting observation, because that’s precisely what a number of cognitive behavioral interventions for depression actually do. It raises the possibility, though, that some form of cognitive training might improve someone’s mood. That possibility is supported by findings from an NIA study of cognitive training (the ACTIVE trial). Researchers showed that participants in cognitive training were less likely to become depressed (click here for the study).
So it looks as though cognitive training may help with mood. If you’re depressed, you shouldn’t rely on cognitive training to help you get better. Talk to a psychologist or someone who can help you with how you’re feeling. Psychotherapy and medication are very helpful to many people. After you take care of all the regular ways of dealing with depression, though, it may be helpful for depression. Remember, depression is a serious condition and should be treated. But is looks as though brain training may be another strategy for routine depression.
Reference: Heller A et al. (2009). Reduced capacity to sustain positive emotion in major depression reflects diminished maintenance of fronto-striatal brain activation. Proceedings of the National Academy of Sciences, 106(52), 22445-22450. Click here for the PNAS site.
