Understanding the biology behind mental health
Dr. Tamás Füzesi and Dr. Stefanie Hassel study how biological changes in the brain can trigger mental health problems.
Story by Jonathan Davies/Illustration by Byron Eggenschwiler
Dr. Tamás Füzesi and Dr. Stefanie Hassel came to the University of Calgary with a similar goal: to investigate the mechanisms through which healthy brains manifest illness. But to achieve that goal, the Alberta Innovates – Health Solutions postdoctoral fellows use different experimental approaches.
With Dr. Jaideep Bains, a leading stress scientist who is also funded by Alberta Innovates – Health Solutions, Dr. Füzesi is working to reduce the effects of chronic stress. Dr. Füzesi became an expert in detecting anatomical changes in the brain, in particular the hypothalamus, at the Hungarian Academy of Sciences. "The hypothalamus plays a very important role in controlling our response to stress," says Dr. Füzesi.
Nerve circuits in the hypothalamus initiate a stress response by stimulating cells in the paraventricular nucleus, a group of neurons in the hypothalamus, to release stress hormones into the bloodstream. Normally, this release is balanced by inhibitory circuits that act as a brake on the stress hormones. However, when the inhibitory circuits are overactivated, they can accelerate hormone release rather than slow it down. "It's very exciting to learn how the hypothalamus handles chronic stress and recovers from challenge," says Dr. Füzesi. He believes certain patterns of stress may cause the remodelling of nerve circuits in the hypothalamus that result in accelerated stress. In Dr. Bains's lab, Dr. Füzesi tests that theory by learning cutting-edge electrophysiology techniques to understand the mechanisms through which those changes occur. Ultimately, he hopes to learn how to interfere with the process and stop stress in its tracks.
Similarly, Dr. Hassel is also trying to understand how biological changes in the brain can lead to disease, but her focus is bipolar disorder. She came from the University of Pittsburgh to Calgary to train with Dr. Glenda MacQueen, an expert in mood disorders and changes in the brain. Dr. Hassel wants to develop more accurate diagnostic techniques for bipolar disorder.
Unlike the normal life events that affect most people's moods, the dramatic and uncontrollable fluctuations between highs (mania) and lows (depression) in people who suffer from bipolar disorder can result in damaged relationships, poor job or school performance, and even suicide. Because the brain changes associated with bipolar disorder are slow and progressive, achieving accurate methods for early diagnosis has been difficult. "We don't have enough early diagnostic markers yet, and as a result, it can be easy to misdiagnose bipolar disorder," says Dr. Hassel.
Bipolar disorder is characterized by an inability to process and control emotion and social behaviour. Using medical imaging techniques such as functional magnetic resonance imaging and diffusion tensor imaging, Dr. Hassel looks for markers and biological changes in the brain that might account for these problems. She expects to see increased impaired function in the prefrontal cortex and limbic system—areas of the brain responsible for emotion, behaviour, and long term memory. “By using neuroimaging techniques to identify biological diagnostic markers such as these, we will hopefully achieve increased diagnostic accuracy. This could lead to better treatment for patients,” says Dr. Hassel.”