Researchers found in the depressed phase, there is high activity in the default mode network, this is where internal thoughts take place, and there is lowered activity in the sensorimotor network, which is involved in physical movement and interaction with the external world.
And when someone is manic, it is exactly the opposite.
How much sense that makes, the symptoms of depression like rumination, lowered activity can be totally explained by the activities of the different brain regions. So can the over interaction with the world and less introspection seen in mania.
What’s a new discovery is that these two areas of the brain, though located far from each other, are in communication with each other.
What the authors are proposing is to measure the activities of these and perhaps other regions in the brain with an fMRI (a functional MRI, which measures changes in blood flow, therefore activity) and then individualizing therapy depending on what was observed in the fMRI.
Being able to measure the activity gives doctors a more objective way to measure someone’s symptoms. So far the only way to gauge symptoms is by asking a patient questions. While I must add that patients can describe their own plight pretty well, I’m not against using fMRI’s, if that becomes the protocol. I’m sure what the patient says and what the fMRI shows will agree to a large degree.
Research that has unlocked some of the mystery of bipolar disorder could lead to personalized treatments for patients — something Ottawa neuroscientist and researcher Dr. Georg Northoff calls the “holy grail”.
Northoff, research director of the Mind, Brain Imaging and Neuroethics unit at the Royal’s Institute of Mental Health Research, led a study that compared brain images of people with bipolar disorder to those of healthy people. The work uncovered changes in the two distinct areas of the brain related to the manic and depressive phases in those with bipolar disorder.
The research was published in the Proceedings of the National Academy of Sciences in the U.S. on Monday.
Using functional magnetic resonance imaging (fMRI), which detects brain activity by measuring changes in blood flow, researchers found that when a patient is depressed there is unusually high activity in their brain’s default mode network and unusually low activity in the sensorimotor network. The opposite is true when a person is in the manic stage of bipolar disorder.
The default mode network, located in the top middle region of the brain, is where internal thoughts take place. The sensorimotor network, found at the outer edge of the brain, is involved with physical movement and interactions with the external world.
“It is the interaction between these two networks that is new,” Northoff said. “This interaction has never been measured before, not even in healthy people.”
The development of imaging that can read activity levels in parts of the brain has been a game changer in a field of medicine that has long relied on interpreting clinical symptoms and treatment largely by trial and error.
Now, as imaging becomes more sophisticated, researchers are about to get a better picture of what is happening inside a patient’s brain. More importantly, they can study how various treatments affect what is going on — such as trying to balance the two networks that are over or under activated in patients with bipolar disorder.
Although treatment for bipolar disorder is standard, Northoff noted that different patients show various degrees of imbalance between the two networks, meaning they would likely respond differently to treatments. Rather than using trial and error to determine what treatment works best, a cutting edge piece of equipment just being installed at the Royal could change the way individual patients are treated and further advance research.
“When you go to your family doctor for blood tests and she sees that your glucose level is abnormal, she will make a decision about your treatment. If you glucose level is extremely high, you will get insulin and she will know exactly how much to give you, depending on your level,” Northoff said.
“That is what I am attempting to do with this research. I want to get individualized ranges of just how depressed or manic a person is. This is essentially my blood test. Based on the results, I can then say, ‘OK, you get this therapy.’”
The $8-million PET-fMRI imaging machine, the subject of a fundraising drive, will officially open at the Royal in May. It measures both neuronal and biochemical activity in the brain. Using it to measure the networks involved with bipolar disorder, Northoff plans to lead a large-scale clinical trial looking at whether individualized therapy based on the results of brain imaging is more effective than therapy prescribed without the use of brain imaging.
Northoff, who was recruited to the University of Ottawa and The Royal in 2009 from Germany, holds doctorates in both psychiatry and philosophy. He has published more than 150 scientific papers as well as a number of books including his most recent, Learning from the Unwell Brain, which explores consciousness by examining examples of unhealthy minds.