In this paper, the author discusses the recurrence of infantile, proto-mental functioning in adolescence mainly in the context of the work of Frances Tustin. She demonstrates, through clinical example, how the tendency to resort to bodily centered and sensationdominated protections is reactivated on a grand scale when the internal and external physical and psychological changes, brought on in puberty, are felt to be potentially overwhelming. She also demonstrates how, when the capacity for adequate mental and emotional development is stultified, sensation and action once again come to the rescue as the adolescent's way of attenuating anxieties unconsciously experienced as resonating with those unmentalized happenings of early infancy and how the psychoanalytic relationship may be pivotal in setting previously derailed mental and emotional growth back on track.