Check out Irresistible: The rise of addictive technology and the business of keeping us hooked, by Adam Alter. (his Ted Talk can be accessed at https://www.ted.com/talks/adam_alter_why_our_screens_make_us_less_happy
Alter does an excellent analysis of the psychological, situational and physiological factors and principles used to get us and keep us hooked to the immediate, intermittent reinforcement of all the activities we might do on the net (text, email, Facebook, shop, game…), and the damage this can cause. Our instant access to these very compelling internet activities available through our tech has fueled a dramatic and alarming increasing in behavioural addiction (Alter, 2017). He cites research that up to 40% of the population, and 48% of American university students, “suffers from some form of Internet-based addiction…to email, gaming or porn…” (p. 86).
Remember, symptoms of behaviour addictions include that the person feels unable to stop the behaviour, and has adverse consequences such as interference with work or school performance, social relationships with family and friends, even physical or financial safety.
Alter also analyzes the reasons why on-line gaming is so addictive, and so possibly damaging to functioning at work or school or in relationships.
Don’t get me wrong, I’ve loved role-laying D & D from the original Gary Gygax era in the early 80’s. But I don’t play on-line games (though often tempted by Legends of Zelda).