(Ap)perceptual distortions in a case of right-hemisphere lesion: Evidence from the tat

A diverse body of recent evidence suggests that patients with anosognosia to hemiplegia following right-hemisphere deficit (RHD) have implicit knowledge of their deficit and that their denial is motivated by the aversive emotional consequences that would accompany full awareness. Recent theories link spatial deficits following RHD with this defensive, psychological need, suggesting that attentional and perceptual processes can be dramatically biased by deep psychological mechanisms. The present study further explores the nature of perceptual biases in a patient with RHD and an anosodiaphoric reaction to cognitive impairment. The patient was asked to tell a story, depicting the events in three Thematic Apperception Test (TAT) cards. The patient’s descriptions revealed systematic distortions of several “objective” features of characters and scenes, which enabled him to view the pictures as exact portrayals of episodes from his own life. These “pure projective” distortions are examined in light of three theories: Ramachandran’s lateralization of “schema sorting” and “incongruency detection” functions; Kaplan-Solms and Solms’s theory of narcissistic regression in right perisylvian lesions; and the Process Approach. Finally, I consider possible implications of these findings for normal, everyday instances, in which visual perception is massively colored by projective mechanisms.