The effect of duration of exposure on systematic desensitization and extinction.
D000818:Animals; D001521:Behavior Therapy; D003887:Desensitization, Psychologic; D005108:Extinction, Psychological; D005239:Fear; D005260:Female; D006801:Humans; D007092:Imagination; D010698:Phobic Disorders / Q000628:therapy*; D011581:Psychological Tests; D012063:Relaxation; D012911:Snakes; D013997:Time Factors; D014796:Visual Perception