I chanced upon this fascinating infopic by Dr Doug Lisle (a psychologist) in the plant-based nutrition course offered by T Colin Campbell Center for Nutrition Studies.
Five Phases of Change by Dr Doug Lisle
The Pleasure Trap can keep us in a state of constantly craving artificially calorie-dense foods until we break out of it. The five phases of change outline the path into the Pleasure Trap as well as the way out of it as it shows how our bodies and minds can adapt to different kinds of stimuli.
Phase 1 - If you are eating whole, natural foods with low calorie density, you have a normal pleasure response to the food you eat.
Phase 2 - You may start eating "supra-normal stimuli," like chocolate apples, and the calorie density fires the pleasure centers in your brain to create an enhanced pleasure response.
Phase 3 - After eating "supra-normal stimuli" regularly, the pleasure centers adapt downward such that high-calorie-density foods lead to a "normal" pleasure response.
Phase 4 - If you then go back to whole, natural foods at that point, the dramatically reduced calorie density will lead to a subnormal pleasure response. Think of trying to eat peas and carrots after eating fried chicken and ice cream.
Phase 5 - If you stick with the whole, natural foods for a short period of time (weeks to a small number of months), the pleasure response will recalibrate such that these low-calorie-density foods fire the normal pleasure response receptors again.