High on pixels?

Dr. Richard Friedman describes in the NYT (“Lasting Pleasures, Robbed by Drug Abuse”) how many of his patients who are addicted to drugs like cocaine seem to lose the ability to enjoy the small things in life. After a while, even the drug itself no longer gives them the same high. And these effects persist even many years after they have kicked the habit. Dr. Friedman explains that mind-altering drugs highjack the reward system of the human brain as they act much more powerfully on it than any natural stimuli. With time, neurons in the brain become less sensitive to all the dopamine being released under the influence of the drug, and pleasure fades away. Is this mechanism activated only by chemical substances, though? I am looking at a review of Fun, Inc. by Tom Chatfield. He thinks that video games are clearly the greatest invention in the history of humanity. Yet, even he recognizes that games are designed to tap into the same reward circuits that are activated by sugar, alcohol, and other drugs. Could they, then have a similar effect, desensitizing the brain to the smaller pleasures of life?