Bulletin of the Menninger Clinic. XLIII, 1979: The Sensory Deprivations. An Approach to the Study of the Emergence of Affects and the Capacity for Object Relations. David A. Freedman. Pp. 29-68.

Three modes of sensory deprivation are explored with respect to their associations with specific and predictable psychological vulnerabilities. These are congenital blindness, congenital deafness, and severe environmental deprival during the first three years of life. While twenty-five percent of congenitally blind infants become autistic, autism in the congenitally deaf appears to be no greater than it is in the general population. Six months seems to be the age by which the parents of congenitally blind children seek consultation for their child's deviant behavior, while parents of congenitally deaf children may wait until they are about three years old. Such observations offer persuasive evidence that during the early development of normal children there is a shift in the sensory modality through which the child perceives and organizes experience. The relation with the mother seems to be critical in organizing and channeling aggression. In the environmentally deprived, absence of contact with the mother limits the basic internalizations which allow for a differentiation of self and nonself. Affect as a subjective event and affective expression are not the same. Affective expression is the more primitive in the maturational time-table and leads to synthesis of the two. Thus, Freedman suggests extending Hartmann's concept of an undifferentiated phase to include all elements of psychological functioning: affects, drives, object relations, and structures. Maturation proceeds according to a gene-determined timetable, but how developmental potentials emerge is a function of the psychological ambience in which they occur, i.e., developmental factors.