Neurologist Judith Grisel

As watering a flooded field is moot, widespread cannabinoid activity, by highlighting everything, conveys nothing. And amid the flood induced by regular marijuana use, the brain dampens its intrinsic machinery to compensate for excessive stimulation. Chronic exposure ultimately impairs our ability to imbue value or importance to experiences that truly warrant it.

In adults, such neuro-adjustment may hamper or derail a successful and otherwise fulfilling life, though these capacities will probably recover with abstinence. But the consequences of this desensitization are more profound, perhaps even permanent, for adolescent brains. Adolescence is a critical period of development, when brain cells are primed to undergo significant organizational changes: Some neural connections are proliferating and strengthening, while others are pared away.
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