The relationship of cognition to affect in normal subjects is similar to that observed in psychopathological states. Among normals the sequence perception-cognition-emotion is dictated largely by the demand character of the stimulus situation. In psychopathological conditions, the reaction to the stimulus situation is determined to a much greater extent by internal processes. The affective response is likely to be excessive or inappropriate because of the idiosyncratic conceptualization of the event. The input from the external situation is molded to conform to the typical schemas activated in these conditions. As a result, interpretations of experience embody arbitrary judgments, overgeneralizations, and distortions. Perserverative conceptualizations relevant to danger, loss, unjustified attack, and self-enhancement are typical of anxiety neuroses, depression, paranoid states, and hypomanic states, respectively.