Motherboard

Research out Thursday from a team based at Mount Sinai Hospital in New York City might not suggest a cure in its purest sense, but it offers something much closer to that than previously obtained: full alleviation, at least in mouse models (which are pretty good models for this sort of thing). What the authors describe in their study is a new and very unexpected target mechanism-the mechanism by which the brain corrects depression on its own in healthy humans or, more specifically, the way it naturally responds to stress.

The discovery points to two different ion channels in the brain-imagine wires-and a group of neurons known as the ventral tegmentum (VTA), the part of the brain that handles neurological reward systems, motivation, cognition, and drug addiction. Naturally, it follows that VTA dysfunction is also thought to be the locus of a number of psychiatric disorders. In depression, particularly, what’s seen is an elevation in VTA neural firing-overactivity. This is thought to be the result of an increase in incoming cation channel currents (Ih currents), which triggers the additional out-of-control firing (“dysregulation”), and a therapeutic focus has been on quieting that channel and the VTA.

The Sinai researchers discovered something very strange about the VTA and its corresponding cation channel. If you increase the current in that channel to very high levels, higher than we would expect in a normal brain, the VTA stimulation effect switches into reverse and the opposite becomes true. The VTA quiets rather than dysregulates, and as a result, the depression bows out. Symptoms disappear. In the case of lab mice, the symptoms disappear completely, as stimuli that would normally cause depression are increased. The researchers attempted two different methods of increasing depression-causing features: using light to stimulate firing within the VTA itself and using drugs to increase the current in the cation channel. The result of both was an increase in natural resistance, specifically as mediated by a third brain (and cardiac) feature, potassium ion (K+) channels.

So, here’s one so cutting edge it’s almost still in the realm of SiFi.

I’ve had many clients talk about their recovery from depression starting when they finally plummeted to depths they never even thought possible and finally couldn’t feel worse. The idea is certainly well recognized by others and has even become the theme of a rather curious autobiography via cartoon strips but no one has ever attempted to understand why this rather counter-intuitive phenomenon occurs.

Well, now we know why — and it may suggest a powerful new line of treatment for at least the non-lifestyle related parts of depression.