The link between addiction, anxiety and depression has long been known. Essentially, if you have one, you are highly likely to have the others. But what is emerging from neuroscience research is how intricately they are all connected and how the stress hormone cortisol can hard-wire the brain to make a person vulnerable to all three.Cortisol is one of the primary hormones released when we are anxious or stressed. Its job is to provide extra energy to deal with the stressor. It does this by partially shutting down certain systems, such as the digestive system and the immune system and flooding the body with glucose. Along, with adrenaline, cortisol is responsible for the body sesnsations we get when we experience fear, anxiety and stress – rapid heart rate, shallow breathing, chest pains, tingling in the arms and hands, dizziness and butterflies in our stomach. Although these feelings are uncomfortable, they are our body’s way of giving us the strength, focus, energy and numbness to pain in order to help us get out of life threatening situations. This is all well and good when we actually have the ability to deal with and take action to remove the stressor but what happens when we can’t?The physical effects of prolonged stress are well documented. Heart disease, stroke, diabetes, reduced immunity and digestive problems are all linked to elevated cortisol levels, but new information is coming to light about how cortisol affects parts of the brain that are central to not only the addictive process but also to depression and anxiety.1. The amygdala
This is the brain’s alarm system that sets off the fight or flight response when it percieves danger. The problem is, it doesn’t know the difference between a real direct threat to our survival and an imagined threat, which might only be a danger to our fragile egos. When we worry about what others think of us or ruminate about what could happen to us in the future, our amygdala starts to signal the release of adrenaline and cortisol. Unfortunately, if the amygdala is over stimulated, it becomes extra sensitive to percieved threats. The more anxiety that is felt, the more reactive the amygdala becomes.
2. Reduction of dopamine and serotonin
When there is too much cortisol running around our systems, the production of “feel good’ chemicals is reduced. Dopamine provides us with feelings of pleasure, focus, motivation and an increased desire to connect and engage with others. Serotonin generates feelings of calm, well-being, optimism and relaxation. Deficiencies in both these neurotransmitters result in feelings of anxiety, agitation, lethargy, restlessness, lack of focus, a negative outlook on life and a propensity for avoiding social contact.
3. The prefrontal cortex (PFC)
The part of the brain that is responsible for regulating emotions and curbing impulsivity becomes less effective when there is excess cortisol. Dopamine and serotonin are required to power the prefrontal cortex and with their reduction comes a reduced ability to regulate our mood and overide impulsive urges.
So anxiety breeds depression, which in turn causes more anxiety. And the perfect antidote – albeit temporarily – is substance use. Drugs and alcohol stimulate the production of dopamine and serotonin and suppress or numb uncomfortable emotions such as anxiety. However, as usage increases, the brain tries to compensate for the over-production of neurotransmitters by shutting down their receptors. So the more you use, the less dopamine and serotonin you get until you are using just to try and feel normal. You also have a reduced ability to manage cravings and urges to use. So on top of the anxiety and depression you now have an addiction.
Given the effects of cortisol on the brain, children who grow up in stressful, abusive, or neglectful environments are likely to have brains that are deficient in dopamine and serotonin; more reactive and sensitive to stress; less able to regulate emotions and are prone to impulsivity. In effect, they are wired for anxiety, depression and addiction. Even in the womb, excess cortisol from stress can affect the developing fetus’ brain a child that startles or cries easily and takes longer to soothe.
But it’s not all doom and gloom. The power of neuroplasticity means that the brain can re-wire and regenerate throughout the life-span given the right conditions.
Learning to manage anxiety, reducing cortisol and finding natural ways to boost dopamine and serotonin are crucial for re-wiring the brain for long term recovery from addiction.