The Neuroscience of Addiction: How it Works in the Brain

Human beings are pleasure-seeking creatures: We chase after food, drink, and activities that make us feel good, and we seek to repeat that behavior. While this pleasure-seeking behavior is at the core of our evolutionary survival, it can also threaten our very existence when it runs amok. Such is the case with drug or alcohol addiction.

The chemistry of addiction takes place deep in the brain, beginning in the ventral tegmental area, which is the body’s reward-seeking center. The VTA, as it’s called for short, releases a chemical called dopamine in response to pleasure. Dopamine travels to a higher region of the brain called the nucleus accumbens, which is responsible for our emotions and motivation. Here, dopamine produces a surge of euphoria and excitement; this causes us to want to repeat the behavior that has just brought us pleasure.

Stimulants such as amphetamines and cocaine cause a tenfold increase the brain’s available amount of dopamine, effectively recalibrating the brain to a “new normal.” If we continue to use these drugs, the brain’s response is to reduce the number of dopamine receptors, until we require more of the same substance to produce the same effect.

Depressants, such as sedatives and alcohol, slow down the brain by inhibiting an excitatory transmitter called glutamate; at the same time, depressants increase GABA, a neurotransmitter that suppresses brain activity. To counteract these effects, the brain must increase its production of adrenaline and norepinephrine, two chemicals that keep us alert and focused.

As we become increasingly dependent on drugs and alcohol, these substances wreak havoc on our bodies. When we come down off our high or wake up after a night of binge drinking, we go through withdrawal as our dopamine levels crash. We have the shakes, headaches, nausea, difficulty breathing, anxiety, and heart palpitations.

In order to counteract the effects of withdrawal, our brain asks for more of the substance that brought it on. This is why we reach for that morning-after drink or hit. Thus, the cycle of addiction continues. Over time, this can cause permanent damage to the brain.

The word addiction comes from the Latin root for “enslavement” – and this is precisely what drugs and alcohol do to us. The cycle can be broken, and help is available. If you or someone you love has a drug or alcohol addiction, reach out to a drug counselor, therapist, treatment center or 12-step group, before it’s too late.


Learning about the illness of addiction helps to save lives. Psychoeducational lectures are part of a comprehensive treatment programme at Smarmore Castle Private Clinic, where lifetime abstinence is the goal. Call us today for information: +353 41 214 5111

Schedule Your Assessment

Smarmore Castle has the facilities and staff to help you regain control of your life, request a call-back from one of our professionals today. The choice you make today could change your life forever.

This field is for validation purposes and should be left unchanged.