A significant number of TAT records do not show pathology because of the paucity of content in the stories or for other reasons. Bellak therefore urges that we 'study apperceptive protocols specifically from the standpoint of the defenses as indicators of personality structure, as criteria of assets and liabilities, and often as the only clues to impulses which themselves may have become completely invisible'. He discusses manifestations of perceptual repression, denial and turning into the opposite, displacement in time or place, reaction-formation against aggression, and other defenses. We need to understand failures in terms of defenses against anxiety, as in the psychoanalytic situation. The TAT presents a special ego problem that requires mental activity which is more controlled than that in nocturnal dreams, which involves a more defined task than do daydreams, and which needs freer rein than does thinking about the structured problems of everyday routine.