Evolution and Depression

Scientific American takes a look at depression from a different perspective in asking if perhaps it’s the result of an evolutionary process that’s more helpful than harmful.

The authors posit that our brains play an important role in survival and reproduction, and therefore they should be resistant to high rates of malfunction. Most mental illness is rare, except for depression. Why is that?

One possible answer is that depression isn’t a disorder at all, but rather an adaptation that brings both costs and benefits.

Here’s an example:

So what could be so useful about depression? Depressed people often think intensely about their problems. These thoughts are called ruminations; they are persistent and depressed people have difficulty thinking about anything else. Numerous studies have also shown that this thinking style is often highly analytical. They dwell on a complex problem, breaking it down into smaller components, which are considered one at a time.

Without completing restating the entire article here, the main point being articulated is that depression is nature’s way of letting you know that you have some complex social problems to solve, and that your brain is actively engaged in seeking those solutions. And rather than attempting to stop depressive ruminations, therapists would be wise to encourage them in an attempt to find the answers to the problems causing the bouts of depression in the first place.

If you’ve suffered from depressive episodes, I’d like your thoughts on this concept. Does this ring true for you?

Link , via Scientific American

Fear On / Off Switch?

This would be very good news for those of us who have issues with having fear, panic, and anxiety responses that don’t work as well as they should.

Researchers at Harvard Medical School’s affiliate McLean Hospital have identified a protein in the brain that serves as a trigger for how we respond to fear, real or imagined. This finding increases the chances that scientists may be able to develop medications that could help regulate this faulty fear switch in people suffering from certain types of anxiety disorders.

In the study, the researchers looked at the neurons in the amygdala of mice lacking the TRPC5 gene and discovered that they did not fire as well as those in the brains of normal mice. At the same time, neurons in the same region of the brain of the mice missing the TRPC5 gene were not as sensitive to the neuropeptide cholecystokinine, commonly released in the brain during situations of innate fear or anxiety…

Let’s hope that this research continues and that we see some pharmaceutical trials of new medications as a result.

Researchers identify a fear on-off switch , via Anxiety Insights

Brain, Electricty, and Panic

Anxiety Insights details an abstract from a Brazilian study that examined the role that abnormalities in midbrain structures might play in panic disorders.

The research demonstrated that electrical stimulation of the periaqueductal gray matter (PAG) produced panic-like symptoms “and the effect of drugs that are effective in the treatment of PD in the simulation of public speaking model of anxiety is in agreement with data from animal models of PD.”

In a head-scratching moment, the study also states that other brain abnormalities outside of the PAG might also be to blame if they are used to process panic and anxiety, so I guess the lesson is that we know a little more about midbrain abnormalities now, but other parts of the brain are also key contributors.

Panic disorder: Is the PAG involved?