Saturday, September 4, 2010
In a guest blog here last year, Cristina Romero had this to report from a talk by Kay Jamison of Johns Hopkins:
The brain is like a pond. It’s like an ecosystem. You want to get the ideal ecosystem and then you don’t want to disturb it very much. ... You want to really create a stable environment.
The brain, like an ecosystem, is highly complex, non-linear, and self-organizing. Both brain scientists and environmentalists describe this self-organizing principle as "homeostasis," where the system maintains its own equilibrium at a particular "set point."
We see this in the cycle of the seasons. But what if a drought or global warming intervenes? That's where "allostasis" kicks in. The system engages in compensatory wobbles to restore its sense of balance, either back to its original set point, or to a new one. That could be going on right now with Mother Earth.
Over the last two decades, southern California has gotten drier. The drought-weakened oaks in San Diego's eastern back country, my home until very recently, have been sitting ducks for certain species of beetles, who lay eggs in the bark crevices. The larvae then bore under the bark, and literally drain the life out of the tree. By the time you see dying leaves, it is too late to save the tree. Literally, a walk in the back country here is a walk along arboreal death row.
It doesn't stop there. The dead and dying trees serve as kindling for wild fires, which the seasonal Santa Ana winds fan like a bellows. In 2004, a once-in-a-century fire raged through the back country and other areas of San Diego, scorching more than a quarter million acres and killing 15 people. In 2007, another once-in-a-century fire struck.
Cycle of nature or planet in crisis? Who knows? The earth will heal one way or the other. It's just that it may no longer look the same or have people in attendance to witness the change. San Diego's Museum of Natural History has a fossilized mastodon skeleton on display, together with a mural depicting the beasts frolicking in the local swamps.
Then global warming happened. The swamps became desert. The earth eventually adjusted - found a new set point - but it was a new world order that did not include the mastodon. (Thanks for the memories.)
Then there is allostatic overload, a state of total collapse. As it happened, late last year I was hiking along the arboreal death rows of San Diego's back county - enjoying the sun, sucking in the type of air that city people would happily pay a dollar a bottle for - as I contemplated a person close to me in a psych ward back east. Back in the old days, they simply would have referred to his condition as a nervous break-down. They got that right. His brain was indeed broken. But which part of the brain was broken? That’s what I wanted to know.
Ha! If only life were so simple. In a review article in Psychiatry, Dhwani Shah MD of the University of Pennsylvania et al point out that “psychiatric syndromes cannot be localized in a single, so-called ‘abnormal’ brain region.” Rather, “mood and anxiety disorders involve immensely complex interconnected systems or networks of organization within the brain.”
Repeat: The brain is an ecosystem, the brain is an ecosystem, the brain is an ecosystem ...
The causes of depression and other mental illnesses are complex and only partly understood. Nevertheless, a picture is beginning to emerge of interconnecting brain systems in allostatic overload on the brink of collapse.
Tell me about it ...