The Science of Drunk Personalities
Alcohol affects the prefrontal cortex, the part of the brain responsible for decision-making, impulse control, and social judgment. As inhibitions lower, personality traits that are normally held in check tend to emerge more strongly. This is why some people become more affectionate, others more philosophical, and some suddenly believe they are exceptional chefs.
Research from the University of Missouri found that most people have a distinct "drunk personality" that differs from their sober self. The study identified four main drunk types: the Mary Poppins (kind and together), the Hemingway (minimal change), the Nutty Professor (uninhibited and outgoing), and the Hyde (more negative personality change). Most people fall somewhere between these types depending on how much they have consumed.
The "will I regret this?" phenomenon is well-documented in psychology. Alcohol reduces activity in the amygdala, which processes fear and consequences, while simultaneously reducing prefrontal cortex activity. The result: actions that would normally trigger a warning feel fine in the moment. This is why decisions made after several drinks often look very different in the morning.