"매 habit = cue → routine → reward 의 basal-ganglia automatization". 매 21-day myth 의 false — Lally 2010 의 median 66 days (range 18-254). 매 2026 의 wearables + LLM coaching + JITAI (just-in-time adaptive intervention) 의 active.
매 핵심
매 habit loop (Duhigg / Wood)
Cue: 매 trigger — time, place, emotional state, preceding action, people.
Routine: 매 behavior 자체.
Reward: 매 reinforcement — neural prediction error.
Craving (Wood addition): 매 anticipation 의 cue→reward.
매 neural substrate
Goal-directed: 매 prefrontal + dorsomedial striatum — early learning.
Habitual: 매 dorsolateral striatum (sensorimotor loop) — automatization.
Switch: 매 overtraining + stable context → habitual takeover.
매 formation 의 핵심 levers
Implementation intentions (Gollwitzer): "When X, I will Y" — 매 효과 size large (d ≈ 0.65).
Context stability: 매 same time + place 의 consistency.
Friction reduction: 매 cue salience ↑, 매 obstacle ↓.
Temptation bundling (Milkman): 매 desired + pleasurable 결합.
Identity-based: 매 "I am someone who..." (Clear).
매 응용
Atomic Habits 의 4 laws (obvious, attractive, easy, satisfying).
Health behavior change (exercise, medication adherence).
defimplementation_intention(goal:str,cue:str,action:str)->str:returnf"When {cue}, I will {action} in service of {goal}."# When I pour my morning coffee, I will do 10 push-ups in service of strength training.
Habit-stacking chain
defstack(anchor:str,new_habit:str,reward:str|None=None)->dict:return{"anchor":anchor,"new_habit":new_habit,"rule":f"After {anchor}, I will {new_habit}.","immediate_reward":reward,}
JITAI delivery decision
defjitai_should_deliver(state:dict)->bool:"""Deliver intervention only when receptive + context-matched + low burden."""return(state["stress"]<0.7andstate["cognitive_load"]<0.6andstate["context_match"]>0.8andstate["recent_interventions_24h"]<3)
Lally formation curve
importnumpyasnpdefautomaticity(day:int,asymptote:float=0.95,k:float=0.04)->float:"""Asymptotic automaticity (Lally 2010 fit)."""returnasymptote*(1-np.exp(-k*day))# day 21 → ~0.58, day 66 → ~0.88
Context-cue salience score
defcue_salience(cue:dict,history:list[dict])->float:"""Higher when cue co-occurs with successful routine."""matches=[hforhinhistoryifall(h.get(k)==vfork,vincue.items())]ifnotmatches:return0.0returnsum(h["completed"]forhinmatches)/len(matches)
매 결정 기준
상황
Strategy
Brand-new habit
implementation intention + context stability
Existing routine + new addition
habit stacking (anchor)
High-friction habit
reduce friction first, then add cue
Reward-poor habit
temptation bundling
Identity-level change
identity-based ("I am the kind of person who...")
Relapse prevention
re-stabilize context, restore cue
기본값: 매 implementation intention + same context daily + 60-90 day window. 매 21-day promise X.
언제: 매 implementation intention drafting, 매 habit-stack anchor 의 brainstorm, 매 obstacle anticipation, 매 daily reflection scaffold.
언제 X: 매 individual psychological diagnosis (e.g., compulsion vs habit) — 매 clinical professional 필수.
❌ 안티패턴
21-day promise: 매 individual variance 무시 — 매 18-254 day range.
Willpower 만 의 의존: 매 ego depletion + decision fatigue — 매 environment design.
Multiple new habits 의 동시: 매 cognitive bandwidth 초과 — 매 1-2 habits 의 sequence.
No cue specification: 매 vague intention ("eat better") — 매 specific cue + action.
Punishing missed days excessively: 매 self-shame spiral — 매 "miss once, never twice" rule.
🧪 검증 / 중복
Verified (Lally et al. 2010 EJSP, Wood "Good Habits, Bad Habits" 2019, Duhigg "Power of Habit", Clear "Atomic Habits", Gollwitzer 1999 meta-analysis).