with visual stimuli, such as vivid colors—red is a trigger color—or a vibration against the skin near our pocket that signals a possible enticing reward, the body responds in predictable ways: a faster heartbeat and the release of a neurotransmitter, dopamine. In human biology, a faster heartbeat and the release of dopamine are meant to be momentary responses that increase the odds of survival in a life-or-death situation. Too much of that kind of stimulus is a bad thing for any human, but the effects are particularly dangerous in children and adolescents. The first wave of consequences
