Aside from keeping us breathing and our hearts beating, the brain is the root of interactions between thoughts and emotions and the rest of the body. Out of that complicated network of neurons and nerve cells, come the directions to our hands and feet that we need to make our ideas a reality. However, in most cases, physical illness is not a choice; you can't decide to get cancer any more than you can just decide to get rid of it. So why do some physical, unhealthy processes appear so linked to cognitive and emotional processes?
Stress is a prime example. It had been clinically proven that increased levels of stress and/or anxiety over a long period of time lead are damaging to physical health. Hair loss, ulcers, dermatological faults, sleep deprivation, stomach aches, migraines and other, surprisingly complex conditions are all potential results of the body overproducing the hormones needed for the flight-or-fight response that acute stress triggers, meant to aid survival in short-term situations, for extended periods of time.
There are also cases where the brain-body messaging system simply does not operate appropriately. Most common in children and youth, this family of somatization disorders includes most prominently, somatic symptom disorder and conversion disorder. Individuals suffering from these disorders may experience anything from abdominal pain to fatigue to sensations of tingling/temporary paralysis to even seizure-like episodes as a result of the brain misinterpreting strong emotions into physical reactions1. School stresses are suddenly able to cause serious medical symptoms, and it can be frustrating to be told that 'they're all in your head'.
Thankfully, as the field of health psychology grows, more and more attention is paid to these sorts of cases, and the true causes - and hopefully, treatments - are coming into light.
1. Kelty Mental Health Resource Centre (). Somatic Symptoms & Somatization Disorders. [ONLINE] Available at: http://keltymentalhealth.ca/Somatization-Disorders. [Last Accessed 5.5.2014].