Brain Plasticity and Chronic Illness: Life Experiences Change the Brain via “Pruning”

Have you ever wished for evidence that life events affect our health because they influence brain plasticity and gene function, rather than because it’s psychological? The links between brain plasticity and chronic illness are real.

Millions of neurons grow in our nervous systems and elsewhere in our bodies as we develop in the womb and throughout childhood.

These neurons, pathways and connections are then either strengthened, weakened, or removed based on our life experiences and other exposures. This process is referred to as “brain plasticity” and is a way in which our brains change and adapt, even in adulthood.

Adverse experiences also influence brain plasticity and chronic illness.

Pruning is a process by which our bodies remove certain cells, cell connections, and pathways. It determines how we grow and develop.

Pruning is a healthy function of nature and is how our bodies and minds are formed by what we learn and experience ⁽¹⁾learn more about pruning on wikipedia.

It is also one of the ways our brains and organ systems are shaped and molded by life experiences ⁽²⁾Schore, A. N. (1994). Affect regulation and the origin of the self: the neurobiology of emotional development. Hillsdale, NJ, Lawrence Erlbaum, including trauma ⁽³⁾Schore, A. N. (2001). “The effects of early relational trauma on right brain development, affect regulation, and infant mental health.” Infant Ment Health J 22(1-2): 201-269., ⁽⁴⁾Francis, R. C. (2012). Epigenetics: how environment shapes our genes. New York, W. W. Norton & Company, ⁽⁵⁾Diamond, M. and J. Hopson (1999). Magic Trees of the Mind: How to Nurture your Child’s Intelligence, Creativity, and Healthy Emotions from Birth Through Adolescence. USA, Penguin Group, Plume: 484, ⁽⁶⁾McFarlane, A. C., et al. (2002). “Biologic models of traumatic memories and post-traumatic stress disorder. The role of neural networks.” Psychiatr Clin North Am 25(2): 253-270, v. Abstract.

Brain Plasticity and Chronic Illness

What we know is that while genetic factors predispose some of us to developing a chronic disease not everyone who develops a chronic illness has a genetic risk. Furthermore, even when we carry genetic risk factors, our genes need to be turned on or off in order to express themselves to affect our risk ⁽⁷⁾Francis, R. C. (2011). Epigenetics: the ultimate mystery of inheritance. New York, W. W. Norton & Company. See Chapter 1.

I’ve introduced how the process of turning genes on and off is directed by epigenetics in an earlier blog post. It suggests why difficult life experiences are one of the causes of chronic disease – and why resolving the effects of trauma may therefore be an important means of healing from chronic illness.

Pruning and epigenetics have been proposed as a cause of autism. What excites researchers is that it also suggests new means of treatment and prevention, such as diet. Diet can cause – as well as reverse – epigenetic changes ⁽⁸⁾Schaevitz, L. R. and J. E. Berger-Sweeney (2012). “Gene-environment interactions and epigenetic pathways in autism: the importance of one-carbon metabolism.” ILAR J 53(3-4): 322-340. Abstract..

The researchers pieced together the steps by which genes can increase a person’s risk of developing schizophrenia.

That risk, they found, is tied to a natural process called synaptic pruning, in which the brain sheds weak or redundant connections between neurons as it matures.

Pruning is likely an important process that influences all kinds of chronic illnesses, including type 1 diabetes (T1D), which is commonly diagnosed in childhood and adolescence when rates of pruning and development of not only the brain but other organ systems are at their highest ⁽¹⁰⁾You can view or download my article: Mead, V. P. (2007). Timing, Bonding, and Trauma: Applications from experience-dependent maturation and traumatic stress provide insights for understanding environmental origins of disease. Advances in Psychology Research. A. M. Columbus, Nova Science Publishers. 49: 1-80. see p. 5.

Treating Trauma Works with Brain Plasticity

Trauma alters the expression of our genes through the process of epigenetics ⁽¹¹⁾Here’s an article proposing how this happens: McFarlane, A. C., et al. (2002). “Biologic models of traumatic memories and post-traumatic stress disorder. The role of neural networks.” Psychiatr Clin North Am 25(2): 253-270, v. Abstract. And epigenetic changes can be reversed ⁽¹²⁾Weaver, I. C., et al. (2004). “Epigenetic programming by maternal behavior.” Nat Neurosci 7(8): 847-854. Recovering from trauma is one potent way of reversing epigenetic changes and turning genes back on or off ⁽¹³⁾Yehuda, R., et al. (2013). “Epigenetic Biomarkers as Predictors and Correlates of Symptom Improvement Following Psychotherapy in Combat Veterans with PTSD.” Front Psychiatry 4: 118.

If trauma is one of the causes of chronic disease the resolution of trauma may be a powerful – and accessible – treatment tool for improving or perhaps even recovering from all kinds of chronic illnesses.

Not all relevant synapses and neurons are removed during the process of pruning. Rather than dying or disappearing, some neurons and the connections between them become weaker or immobilized ⁽¹⁴⁾Doidge, N. (2015). The Brain’s Way of Healing: Remarkable Discoveries and Recoveries from the Frontiers of Neuroplasticity Viking Adult, see chapter 3.

Through treatment, however, neurons can be reactivated, synapse connectivity reformed and strengthened, and neuronal activity resumed ⁽¹⁵⁾Doidge, N. (2015). The Brain’s Way of Healing: Remarkable Discoveries and Recoveries from the Frontiers of Neuroplasticity Viking Adult, see chapter 3, ⁽¹⁶⁾Rice, D. and S. Barone, Jr. (2000). “Critical periods of vulnerability for the developing nervous system: evidence from humans and animal models.” Environ Health Perspect 108 Suppl 3: 511-533, ⁽¹⁷⁾Schore, A. N. (1994). Affect regulation and the origin of the self: the neurobiology of emotional development. Hillsdale, NJ, Lawrence Erlbaum.

This is how we are sometimes able to improve our health through our actions – such as with diet, exercise, and meditation – and trauma resolution.

This is the beauty of the emerging science. It explains links between brain plasticity and chronic illness – both as a risk factor and as a way the body heals.

Our innate capacity for adaptation is why healing from life-altering experiences such as trauma can be an effective tool for treating – as well as preventing – chronic diseases of all kinds, especially for those of us who don’t respond to anything else.

Learn about tools for treating chronic illness from a trauma perspective under my menu header “Tools” as well as on the page “Therapies for Healing“

Related Posts:

Epigenetics: Why Chronic Illness may be Reversible

The Chronic Illness Model: 11 Characteristics of Trauma and Early Life Events that Affect Risk for Chronic Illness