By Sydney Bright, Edited by Christopher M. Cirino, DO MPH

An estimated fifty-five percent of the world’s population lives in cities. However, our brains did not evolve in the setting of today’s concrete jungles. Modern life contains many stressors, and it requires an incredible amount of cognitive activity and mental processing to manage them. We often overlook the influence of technology and urban living on our habits, for it is all we have known for generations. We don’t always consider the ramifications of these mental and cognitive habits on our health. Nor do we imagine the powerful impact of simple mindfulness practices on our lives.

Brain patterns develop by habit all the way down to the neuronal level. Neuronal activity and abundance follow the “use it or lose it” principle. In brief, when neurons activate, they grow and increase in neurotransmitter abundance. The same concept applies when a certain brain region activates: it will grow in size and increase its influence and activity (Hebb’s theory).

Mental habits translate into physical structures that lead to behavioral change. The behaviors we reinforce in our minds, especially those related to cognitive demand and stress, have a potentially profound impact on our mental and physical health. To combat these modern influences and return to a more physiologically balanced state of being, one should consider incorporating a healthy mindfulness practice into their life. 

The Problem – Repetitive Unconstructive Thoughts and Stress

Many of us have likely heard about the mind-body relationship, but few consider the true gravity of the idea in our daily lives. Not to mention, the concept has not gained much traction in the current health care practice. Nonetheless, it is fascinating to consider the true extent to which our mental habits induce physical changes within our body and how our mental habits influence health. 

Something that most of us take for granted in the modern world is our incredibly busy mind. Inside each of us is a world of thoughts, some constructive, yet some unconstructive. Repetitive unconstructive thoughts can lead to depression (Watkins, 2008). Depression correlates with the stress response and an excess release of cortisol (Kasala et al., 2014). 

It’s easy to understand that repetitive unconstructive thoughts can contribute to stress. However, stress changes the structure of the brain. A postmortem study found that those living a stressful life had larger amygdala volume, a part of the brain corresponding to the “fight or flight” response (Rubinow et al., 2016). Brain size indicates activity and usage. 

The more a neuron fires, the more it will propagate and grow. Going back to the “use it or lose it” principle, the patterns and habits of the brain will further promote the continuation of said habit. The amygdala is thought to largely play a role in emotional regulation (Desbordes et al., 2012). This is likely why stress and depression are found in individuals that have hyperactivity in the amygdala. 

One of the brain’s prefrontal cortex roles is to regulate the amygdala and prevent hyperactivity (Amiel Rosenkranz & Grace, 2002; Davidson, 2001; Lu et al., 2012). Mental habits that do not promote pre-frontal cortex (PFC) inhibition of the amygdala lead to hyperactivity and depressive symptoms. (Annells et al., 2016). Therefore, an important question must be asked: What mental habit can promote PFC inhibition of the amygdala?

A Solution – Mindfulness Meditation

There is growing attention toward mindfulness meditation as an effective technique in alleviating stress, anxiety, and depression within the wellness community. Mindfulness can be described as self-regulation of attention on the immediate experiences of the present, alongside an orientation toward the experienced stimuli characterized by curiosity, openness, and acceptance (Bishop et al., 2004). Multiple studies on mindfulness-based training therapies have shown its strong effect on decreasing stress, anxiety, and depression (Greeson et al., 2018; Petterson & Olson, 2017; Querstret et al., 2020). 

These observations are often coupled with the observation that those who practice meditation have decreased ruminations, alongside increased non-reactive and non-judgmental awareness (Deyo et al., 2009; Querstret et al., 2020). This active practice of reorienting our perception of the present in an open and non-judgmental way seems to be imperative to removing the repetitive unconstructive thoughts from our minds. This mental practice also seems to properly rewire our brain physiology towards a place of greater regulation and balance. 

Mindfulness increases prefrontal cortex activation and reduces amygdala activity even in novice practitioners (Creswell et al., 2007). Therefore, mindfulness meditation, and the mental practices involved, can be seen as an effective habit that promotes the prevention of amygdala hyperactivity. A study showed that long-term meditators have a faster recovery from stress (Gamaiunova et al., 2019), and those who practice mindfulness have decreased occurrences of stress-related physical symptoms (Greeson et al., 2018).

The patterns of the mind and the structure of the brain are not fixed. Alternatively, they are strongly dictated by the habits that we foster. Moreover, habit formation is self-perpetuating. The more one practices a certain mental habit, the more one will have that mental habit in the future. This habit can either be health-promoting or likewise. Of course, the mind and the body share a distinct relationship. Not only do mental habits and physical brain structures share a cyclical influence, but so do mental behavior and physical behavior. 

Mindfulness and Our Behavior

Patterns generate other patterns, and habits lead to other habits. It is important to consider that our thoughts lead to actions and how these actions lead to practices that influence the body and mind. These behaviors revolve around a cycle, pushing us towards our paths and well-being. In this context, our mental patterns influence stress and anxiety, and therefore brain structure. These changes are not simply physical, nor do they affect the quality of mental well-being. These changes can also generate lifestyle habits that further degrade health. 

Depression can greatly impair hippocampal function (Annells et al., 2016), and this is possibly mediated by amygdala hyperactivity (Kim et al., 2006). Stress-induced hippocampal memory, accompanied by decreased hippocampal volume, seems to bias toward cautious and anxiety-prone behavior (Cameron & Schoenfeld, 2018). Humans, like other animals, are habit-forming creatures. Our bodies evolved to adapt to our environment to optimize survival. 

The hippocampus, being the memory storage area of the brain, is highly influential in how the body responds to a new stimulus. Stress-related memories largely influence the hippocampus and dictate how the individual reacts to life events. Those prone to stressors will more often respond to situations in life as if they are dangerous and will react in fear-prone ways to keep themselves safe. Simply put, stress responses facilitate future stress responses.

Of course, our bodies evolved in a much more dangerous environment than our modern one, and this fear is often misplaced and can lead to poor life habits and health. Fear-driven decision-making is not the only observed behavioral consequence of stress either. A review article in 2008 showed that stress is a key factor in facilitating addictive drug use (Cleck & Blendy, 2008).  Not only does stress increase drug craving, but it increases the chance for relapse (Cleck & Blendy, 2008). Stress drives addictive behaviors that further deteriorate health. These poor habits will likely further deteriorate the state of the mind and body, further promoting poor mental habits and, therefore, behaviors. 

The Lesson – Mindfulness Heals 

Our everyday decisions, both mentally and physically, cause a ripple effect in both our inner and outer selves. It can be extremely difficult to understand what all those effects may be. Regardless, an incredible amount of scientific evidence exists to show our minds’ profound impact on our bodies. Our modern world and our modern stressors, promote a mind full of pollution.

Meditation and other mindfulness-related practices are extremely powerful methods in creating a habit in the mind that promotes tranquility and health. Moreover, one doesn’t have to live in a monastery to gain these effects, and a small daily practice can have a profound benefit. Our body, mind, and life are precious. Let us be kind and take care of them.

About the Author

Passionate about understanding the human body in terms of health and happiness, Sydney Bright aims to use modern scientific research to promote more ancient wisdom. As a young child, Sydney attended a Chinese immersion school, where he was introduced to not only the Chinese language, but Chinese culture and traditions. His immersion education continued through high school, instilling within him a deep respect for philosophies surrounding holistic health and well-being. With a Master of Science degree, Sydney dives deep into the scientific literature to explain the importance of holistic health, in a new and modern way. It is his sincere intent and hope that those who read his work gain a new perspective on how to promote well-being in their own lives.  Check out his website The Mindful Inquisitor.

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