Assuming too much from 'familiar' brain potentials.

Familiarity is sometimes associated with midfrontal old/new (FN400) signals, but investigators assume too much by inferring familiarity whenever they identify these signals. We describe how Rosburg and colleagues (2011) made this assumption, yielding potentially faulty conclusions about the recognition heuristic. We provide an alternative interpretation emphasizing implicit processing that can underlie decision-making.