TV & video games
Research agrees that video games doesn't cause excessively violent behavior, but I do have to admit that it seems video games may be addictive for some people, and in particular, for certain personalities. Some studies have found symptoms of withdrawal in a very small subset of subjects; they became moody, agitated, and had physical symptoms of withdrawal.
Television addiction may cause some users to elicit the signs of a behavioral addiction— users often watch TV to change mood, but the relief that’s gotten is only temporary, and often brings them back for more.
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