One of the major stories in bipolar over the past decade is the growing recognition that the condition is way more than a mood disorder. On one hand, we are talking about the thinking cortical regions that fail to boot up properly, even in euthymic (well) patients. On the other, we are talking about the reactive limbic regions that boot up all too well. Too frequently the neural networks that connect the two are severely compromised. Bad things happen.
At the 9th International Bipolar Conference that wrapped up on Sunday, Stephen Strakowski of the University of Cincinnati presented the equivalent of a master’s class.
Above is a representation of the anterior limbic network (ALN). Forget for the time being about specific brain regions and which region is responsible for what. Instead, check out the arrows in the picture that represent how these regions talk and cross-talk with one another. In a 2006 article on CNS Spectrums, Dr Strakowski refers to the old brain science as a “form of phrenology” that wrongly suggested that specific portions of the brain are associated with specific cognitive and emotional traits. Rather:
More recent neuroimaging studies suggest that emotion regulation is an emergent phenomenon that arises out of specific neural networks and that bipolar disorder represents the consequences of dysregulation in these networks.
Okay, let’s see how this works. In a 2004 brain scan study, euthymic bipolar patients performed as well on a simple cognitive task as the healthy controls, but to keep up the bipolars had to activate more brain regions. Dr Strakowski in his talk disclosed he had originally misinterpreted the results. What happened, he said, on later reflection was that the amygdala (which mediates arousal and fear) in the bipolar subjects lit up like a Christmas tree. To compensate for the over-active amygdala, the bipolars recruited the ventral medial prefrontal cortex (VMPFC). Image below.
So, even in routine situations, our brains are subject to stress. And to make up for it, we have to work the thinking parts of the brain harder. No harm, no foul, right?
In another experiment, Stakowski and his colleagues turned up the heat. This time, the subjects were put through a more complex cognitive task called the “counting Stroop,” which involves sorting out incongruent images in rapid succession (such as the number four spelled out three times). In this task, the bipolars scored rather worse than the healthy controls.
Here’s where it really gets interesting. As the task got more difficult, the controls were successful in easing back and slowing down their reaction times, allowing them precious micro-seconds to bring the cognitive areas of the brain online, in particular the regions involved in impulse-control. The bipolars, by contrast, failed miserably in this regard. They kept plowing ahead.
In another study, involving a facial recognition task, Strakowski and his colleagues found difficulties in bipolars in recruiting the VMPFC to suppress amygdala over-activity, resulting in loss of prefrontal control over the brain. In yet another study, the cingulate in the midbrain failed to sort out background noise. On and on it went.
So, imagine yourself in a crowded room this time, not in a brain scan machine. Even the routine task of talking to someone you feel comfortable with may be stressful. Then a stranger sidles over. Meanwhile, you are finding it difficult to tune out a million and one things going on in the room. Everything seems to be closing in. Then your mother-in-law barges in and starts yapping away.
Maybe you rise to the occasion and handle the situation superbly. But you know there is going to be hell to pay some time later. In all likelihood, you will arrive home, either feeling like a wrung-out dish rag or with racing thoughts - or maybe both - needing at least a precious day of recovery time you don’t have. Heaven forbid if you have an important meeting with your boss first thing in the morning.
Obviously, the recovery techniques we have at our disposal help enormously - from the tricks we pick up in cognitive-behavioral therapy to mindfulness to stopping to smell the roses. But when I addressed the panel on the topic of skills training, I was met with blank stares. Here’s where I am coming from:
Two years ago, at the International Congress on Schizophrenia, I happened to walk into a session entitled, "Optimizing Cognitive Training Approaches in Schizophrenia." From a blog piece, Figuring Our Schizophrenia, I did soon after ...
Translation: The brain is plastic. As Michael Merzenich of UCSF describes it, "Basically, we create ourselves."
The brain is born stupid, then evolves and becomes "massively optimized to fit into your world."
In recognition of this, a relatively new field is opening up that involves drilling patients in cognitive tasks we tend to take for granted, such as holding a thought in our working memory long enough to lay down new neural roadwork or responding to stimuli in a timely fashion.
New computer programs are being developed and being tested on patients, Sophia Vinogradov of UCSF explains, and we are seeing enduring changes in the cognitive performance of patients six months later.
Naturally, I was flabbergasted to find the panelists at the Bipolar Conference wholly ignorant to this, but then again I wasn’t surprised. Despite the fact that the schizophrenia researchers are light-years ahead of the bipolar researchers (aided by infinitely more research dollars) bipolar researchers do not seek them out. Carol Tamminga of the University of Texas, a prominent schizophrenia researcher, was far more polite when she addressed the Bipolar Conference four years earlier, simply referring to the lack of cross-talk between the two fields.
Fortunately, after the seminar, someone sought me out and validated my query, referring to Dr Merzenich and a website involving his work called positscience, which provides some online samples of these cognitive drills. Bipolar is five years behind schizophrenia, my informant acknowledged.
One more point: The studies Dr Strakowski and others perform are designed to catch us at our cognitive worst. These studies are comparatively easy to design and execute. Studies that would catch us at our best - formulating a creative response, thinking outside the box, reaching an intuitive insight - simply do not exist. We know our brains are precision-tooled for this, and researchers such as Nancy Andreasen of the University of Iowa are studying the phenomena very intently. But there is no way to capture the birth of a creative idea in a brain scan machine.
But at least a picture - good and bad - is beginning to emerge of what is going on beneath the hood. And in this type of self-knowledge lies the key to leading more fulfilling lives than we could have imagined when we were initially blindsided by this illness. Be hopeful. Knowledge is necessity.
Sunday, June 12, 2011
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3 comments:
Wow. And oh wow. I have been writing about recovery from cognitive deficits, comparing my story to that of a NAMI presenter who had a stroke. He is doing rehab for his cognitive deficits. When writing my post, the shadow of a thought crossed my mind, that he had exercises to do to help with this. Where would I find similar exercises?
Since I have no idea where to find bipolar rehab exercises, which evidently is because they do not exist, I forgot that thought and concentrated on what we do have, the "rest cure." Which, at least, is something.
Oh, how I hope somebody got interested by what you said and does some work in this area!
Thanks for validating me, Willa. Do you know how weird it feels to stump a panel of brain scientists who have four times the IQ you do? I have a funny feeling we can apply these schizophrenia cognitive drills right off the rack. We can build designer bipolar programs later.
Imagine what it would be like to walk into a room totally on your cognitive game, with your stress firmly in control. This could be revolutionary.
I'm going to look further into this, and I suspect you are, too. Please-please-please - scoop me.
Thanks for your last words here on being hopeful. I needed to hear that.
I am a trained scientist and teacher (chemistry and biology) and I just read through these two posts rather quickly, and I really appreciate your skill as a journalist in giving examples. It is all too much for me to absorb right now, but I do plan to reread when my attention span is better.
Keep up the excellent work.
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