Over the last decade a number of studies and books have likened willpower to a single muscle. According to this model, all of our choices and temptations are tugging on the same “muscle” in the brain. So the strain of resisting a luscious chocolate chip cookie in front of us may leave us with less willpower to stick with a difficult test afterward.

The model is useful in understanding, for example, why even health-conscious people may find themselves making grossly unhealthy choices when driving through McDonald’s. You are in a hurry; you are hungry; you are confronted by a dizzying menu of items, combinations, and prices — and prodded with more choices by voice prompts. You leave feeling vaguely guilty, asking yourself, “Why did I agree to be supersized?” And the answer is that the drive-through experience was designed to stretch your willpower “muscle” to the breaking point — and it worked.

Now, researchers from Kellogg School of Management at Northwestern University are proposing a similar model to explain more complex behaviors, such as what happens when we lose our inhibitions, either from being drunk, being anonymous, or being powerful. According to a paper published in Perspectives on Psychological Science, these three states seem very different, but each one blocks the same neurological system — the behavioral inhibition system — that regulates behavior.

Very briefly, here’s how it works:

Intoxication: Consuming too much alcohol decreases cognitive resources, and only the most prominent cues will guide behavior in this state. Thus, pre-existing attitudes and personality traits may be expressed more freely, such as aggressive tendencies or risky sexual decision-making. At the same time, however, inebriated individuals tend to be more helpful than their sober counterparts when the situation calls for heroism.

Anonymity: A cloaked identity serves to reduce social desirability concerns and external constraints on action. As such, an individual may be less inclined to maintain normal levels of what’s socially acceptable. This could result in higher levels of honesty and self-disclosure — or heightened aggression and verbal abuse — in an anonymous chat room.

Social Power: Powerful people are used to relative abundance and have an increased inclination to pursue potential rewards. Because the experience of power increases a “goal and reward” focus, individuals feel less restrained in expressing their current motives, regardless of the social implications. The researchers argue that of these three processes — cognitive exhaustion, lack of social concerns, and a reward focus — all block the same neurological system. And the combination of these forces (e.g., a powerful person who has been imbibing all night and then goes into an anonymous chat room) is likely to be the most disinhibited, for better or for worse.

“When people lose their inhibitions — from being drunk, powerful, or acting anonymously — there can be significant behavioral consequences. In effect, disinhibition can both reveal and shape the person, as contradictory as that may sound,” explains Adam Galinsky, the Morris and Alice Kaplan Professor of Ethics and Decisions in Management at Kellogg. Dr. Galinsky also notes, “Although the powerful and inebriated might be more willing to help during an emergency, it may be best to turn on the lights and hide the alcohol to avoid acting on selfish inclinations.”