effects. Collectively, these responses may serve as a protective factor underlying these drinkers’ ability to “put the brakes on” and limit their drinking. Taken together, the results indicate that the low-level response theory should be revised to include heightened sensitivity to rewarding and stimulating alcohol effects as equally important predictors as lack of sedative responses in the development and maintenance of problematic drinking among at-risk persons. Furthermore, we propose a modified differentiator model to focus on stimulant, rewarding, and sedative effects without connection to a specific BrAC limb or, conversely, to simplify the model and to focus on effects observed during peak BrAC.