“Remember: synapses used are synapses strengthened; they are the ruts in the garden where rainwater flows, forming deeper and deeper troughs. The congealing and narrowing of synaptic traffic, crisscrossing among the OFC, the amygdala, the VTA, and the ventral striatum, leave less and less choice. There are fewer routes to take with each replay of the fundamental story line. Leading to more repetition, less flexibility; more habit, less choice. The psychological realities of diminished choice and narrowed interests—those well-known attributes of addiction—are precisely paralleled by the neural reality of reduced flexibility in synaptic traffic patterns. But here’s the thing: the brain doesn’t really parallel”

― Marc Lewis, Memoirs of an Addicted Brain: A Neuroscientist Examines his Former Life on Drugs