Take some time to take this in: “Your brain creates all facets of your life. So then, why do we treat mental and physical illnesses so differently if we think we know that the mind comes from the brain?”
Neuroscientist Dr. Kay M. Tye studies the neurobiological mechanisms underlying various complex emotional processes such as anxiety and depression. She delivered an intriguing TED talk titled “What investigating neural pathways can reveal about mental health” on the significance of the brain to mental health, using her own research findings. You can find the complete version of this talk here. For some snippets of it, keep reading this blog.
At the onset, Dr. Tye introduces the technique optogenetics which allows the control of specific neural circuits with light. Neurons can be genetically engineered so that they are light-sensitive – fire in the presence of light and shut down in the dark – so that we can use light to figure out what that particular neural circuit does aka how it affects behaviour.
The amygdala is important for regulating emotions, particularly fear, and the work by Dr. Tye’s team has found that activating one path drives positive emotion and activating another path drives negative emotion (see image below), using optogenetics tools
An example of an experiment they conducted: Optogenetics tools were used to control the firing of a particular pathway in the amygdala in mice (ChR2 in basolateral amygdala terminals), which is found to be abnormal in anxiety patients. An elevated plus maze was used to measure their anxiety-like behaviour. This maze has both closed arms and open arms (see image below). Animals that spend more time in the safety of the closed arms relative to exploring the open arms, demonstrate more anxiety-like behaviour.
The moment that particular pathway was activated with light, the mouse started to spend more time exploring the open ends, when it previously preferred to stick to the closed arms before the pathway was activated. This signifies the importance of the activation of that pathway for reduced anxiety-like behaviour in the mouse.
Take away: Making specific changes to neural circuits in the brain can have specific changes in behaviour. Our emotional states have a biological basis aka the physical basis of the mind is the brain. So why does there need to be so much stigma with mental health? Brain health is a significant portion of mental health.
What do we do for better mental health? It is an undeniable fact that the brain IS affected in mental disease and it IS crucial to study this organ to potentially uncover more effective interventions. Various lifestyle factors such as stress, reduced physical activity, poor social connections, coupled with at-risk genes can contribute to mental disease. Collectively these events can shape the brain’s neural circuitry, and hence our behaviour, for the worse. Diagnosis needs to be based on risk factors, behavioural symptoms AND brain activity. Treatments need to be holistic and focus not only on the psychological aspects (therapy to alleviate emotional distress) or the biological aspects (drugs to relieve symptoms) but a combination of both.
Dr. Tye mentions that there hasn’t been much progress in devising new treatments for mental diseases since the 1950s. Given the advancement in neuroscience research on mental health, we now know that the problem is not only primarily about neurochemical imbalances but more to do with faulty neural pathways, entire brain regions and networks. Hence, emerging interventions need to focus on modulating maladaptive neural circuitry aka taking care of your brain is absolutely important for good mental health. The good news is that our brains are malleable – you can build the brain you want! You can learn healthy habits during therapy and unlearn bad ones, like toxic, negative thinking patterns. Repetitive action literally changes the brain, the structure and therefore our behaviour. Dr. Tye envisions that this neural circuit reprogramming has the potential to be not just a treatment but a cure for mental illness. Take charge of your mental health today, be there for others, remind yourself that there is help out there and that we are all in this together and there is always a way <3