Psychoneuroimmunology (PNI) is the science of body mind medicine and its connection between psychological processes (brain) and the nervous and immune systems of the body.

The field grew from the work of Russian psychologist Ivan Pavlov and his classical conditioning model. Pavlov was able to condition dogs to salivate when they heard the ring of a bell by ringing a bell when they were given food.

Eventually, they came to automatically associate the sound of the bell with the act of eating, so that when the food was no longer given, the sound of the bell would automatically cause them to salivate.

PNI focuses on how mental and emotional stress can physically effect how the body works.

Stress has the ability to reduce one’s coping ability and negatively impact nervous system responses and ultimately, impair immune function. Furthermore, long term stress and traumatic life events prime the stress response system so that it reacts more rapidly to subsequent life stressors, which has been shown to have a significant role in many chronic diseases.


According to Steven Maier, PhD, professor of psychology at the University of Colorado, who has researched what he calls the body’s ‘sickness response’, a series of physiological and behavioural changes occur when the body detects an infection. This response triggers changes in liver metabolism, body temperature, increased anxiety, decreased sexual activity and stimulates the stress response, which releases key hormones such as cortisol and adrenaline.

According to Maier, the sickness pattern is an orchestrated attempt to produce energy for fighting infection and to preserve energy through behaviour changes.

It turns out that stress taps into this very same circuit, but starting in the brain rather than the immune system. “Stress is another form of infection,” he said. “And the consequences of stress are mediated by the activation of circuits that actually evolved to defend against infection.”

What Maier found was that the implications of this shared neural loop are that stress and infection sensitize the body’s reaction to the other. In other words, an infection primes the circuit so that it has an exaggerated response to later stress and vice versa.

From an evolutionary perspective this makes sense

If we’re were under stress, about to be attacked by a sabre tooth tiger, for example, our immune response would need to be ready in case of injury.

Numerous studies have shown that stress reduction and the enhancement of wellbeing can boost the immune system and nervous system, as well as helping prevent disease.

One of the best tools to do this is LAUGTHER!

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Research has shown that laughter changes our brain chemistry and strengthens our immune system

Unfortunately however, many people don’t get enough laughter in their day. In fact one study suggests that healthy children may laugh as much as 400 times per day, but adults tend to laugh only 15 times per day.

Laughter reduces the level of stress hormones like cortisol and adrenaline, while increasing levels of health-enhancing hormones like endorphins.

SThrough humour, you can soften some of the worst blows that life delivers. And once you find laughter, no matter how painful your situation might be, you can survive.

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