Addiction Changes Brain's Reward System

Pathological Pursuit of Rewards Fuels Relapse

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Addiction Makes Pathological Changes to Brain. © Getty Images

Pursuing rewards is a normal, healthy activity for most of us. The pursuit of happiness in one form or another is the motivation for us to get up in the morning and go to work or school. Whether we gain happiness from the work itself or we work so that we can achieve other goals that we find rewarding, pursuing those rewards drives us.

However, when the pursuit of rewards becomes obsessive, compulsive or impulsive, so that it begins to dominate our lives and continues even after negative consequences, it can become an addiction.

After the addictive behavior is no longer pleasurable, the pursuit of rewards reaches the pathological state.

Not Being Able to Quit

If you have ever developed an addiction, whether to alcohol, drugs or an activity such as gambling or sex, chances are you have experienced some negative effects and, as a result, have tried to stop. If you were truly addicted, chances are you found that it was not so easy to quit.

Likewise, if you are a friend or family member of someone who has an addiction, you have probably become frustrated and bewildered when the person swore to you and to himself that they would never do it again, but a short time later repeated the addictive behavior.

Pathological Pursuit of Rewards

If this has happened to you, you probably found yourself absolutely dumbfounded that you returned to the addictive behavior after knowing it would cause even more trouble. You may be even more amazed to find that you keep repeating the behavior even after it no longer gives you the same pleasure that it once did.

This state of addiction, when the activity continues in spite of negative consequences and despite the fact it is no longer rewarding, is termed by addiction experts the "pathological pursuit of rewards." It is the result of chemical changes in the reward circuitry of the brain.

How Addiction Gets Started

The reason that people engage in activity that can become addictive in the first place is either to achieve a feeling of euphoria or to relieve an emotional state of dysphoria - discomfort, dissatisfaction, anxiety or restlessness.

When they drink, take drugs or participate in other reward-seeking behavior - such as gambling, eating or having sex - they experience a "high" that gives them the reward or relief they are seeking.

This high is the result of increased dopamine and opioid peptide activity in the brain's reward circuits. But after the high they experience, there is a neurochemical rebound that causes the reward function of the brain to drop below the original normal level. When the activity is repeated, the same level of euphoria or relief is not achieved.

Simply put, the person never really gets as high as they did that first time.

Lower Highs and Lower Lows

Added to the fact that the addict develops a tolerance to the high - requiring more to try to achieve the same level of euphoria - is the fact that the person does not develop a tolerance to the emotional low they feel afterward. Rather than return to "normal," they revert to a deeper state of dysphoria.

For those who have become addicted, they increase the amount of drugs they take, alcohol they drink or increase the frequency of other addictive behaviors in an effort to get back to that initial euphoric state.

In fact they end up experiencing a deeper and deeper low as the brain's reward circuitry reacts to the cycle of intoxication and withdrawal.

When Reward-Seeking Becomes Pathological

According to the American Society of Addiction Medicine (ASAM) this is the point at which the pursuit of rewards becomes pathological:

  • Reward seeking become compulsive or impulsive.
  • The behavior ceases to be pleasurable.
  • The behavior no longer provides relief.

No Longer a Function of Choice

To put it another way, the addicted person finds themselves compelled - despite their own intentions to stop - to repeat behaviors that are no longer rewarding to try to escape an overwhelming feeling of being ill at ease. But they find no relief.

According to ASAM, at this point addiction is no longer solely a function of choice. Consequently, the state of addiction is a miserable place to be, for the addict and for those around them.

If you think you have become addicted to a substance or an activity, you may want to answer these questions to determine if you could benefit from professional treatment. It's not just alcohol and drugs that you can become addicted to, there is a long list of behaviors that can become addictive.


American Society of Addiction Medicine. "The Definition of Addiction (Long Version). 15 August 2011.

American Society of Addiction Medicine. "Definition Of Addiction: Frequently Asked Questions (PDF)," 15 August 2011.

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