Why the modern world is bad for your brain | Science | The Guardian

Each time we dispatch an email in one way or another, we feel a sense of accomplishment, and our brain gets a dollop of reward hormones telling us we accomplished something. Each time we check a Twitter feed or Facebook update, we encounter something novel and feel more connected socially (in a kind of weird, impersonal cyber way) and get another dollop of reward hormones. But remember, it is the dumb, novelty-seeking portion of the brain driving the limbic system that induces this feeling of pleasure, not the planning, scheduling, higher-level thought centres in the prefrontal cortex. Make no mistake: email-, Facebook- and Twitter-checking constitute a neural addiction.
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