WHO's move to classify gaming disorder as a mental health condition has revived a debate about whether or not certain substances and behaviors can cause the same addictive illness as drugs.

In its strictest definition, addiction is a disease caused by changes in brain chemistry linked to use of drugs or alcohol and characterized by excessive use that damages aspects of a normal life. Brain studies show that excessive gaming may have an effect on the brain in similar ways.

Brain's Reward Circuit

Certain drugs, such as opioids and alcohol can over-activate the reward circuit of the brain, which is normally activated when people engage in behaviors crucial to survival such as eating when hungry and drinking water when thirsty.

Dopamine helps regulate these behaviors but drugs can flood the brain with the brain chemical which can encourage repeated use and make use of these drugs more rewarding than healthy behaviors.

A person would eventually need increasing amounts of these substances to have the same effect and brain changes, which can lead to an inability to control use.

Caffeine also has the same effect but to a lesser degree. Its reward is making people feel more alert and those who frequently consume them can develop mild withdrawals symptoms when they stop taking these caffeinated products.

Some coffee drinkers develop tolerance and need to consume more to get the same sense of alertness. WHO recognizes caffeine dependence as a disorder but the American Psychiatric Association said that more research is needed to classify it as such.

Can Playing Video Games Lead To Addiction?

The manual used by the American Psychiatric Association for diagnosing mental illness described video gaming as a condition and not a formal diagnosis or disease.

Ellen Selkie, from the University of Michigan, said that addiction is an inability to control use to a point where a person is failing at life.

Compulsive gambling is the only behavior the American Psychiatric Association classified as an addiction. Gamblers need to show several symptoms which include lying to hide their gambling, restlessness or irritability when trying to stop, and loss of jobs and relationships because of gambling activities.

Research has shown that excessive gambling can have the same effect on the brain as addiction, and excessive video gaming may have the same effect.

"For gaming disorder to be diagnosed, the behaviour pattern must be of sufficient severity to result in significant impairment in personal, family, social, educational, occupational or other important areas of functioning and would normally have been evident for at least 12 months," WHO said.