DSM+II+1968

Short arm deletion of chromosome 18—group £.
DEFINITIONS OF TERMS 21
Abnormal morphology of chromosomes, other. This category includes
a variety of translocations, ring chromosomes, fragments, and isochromosomes
associated with mental retardation.
.6 Associated with prematurity
This category includes retarded patients who had a birth weight of less
than 2500 grams (5.5 pounds) and/or a gestational age of less than
38 weeks at birth, and who do not fall into any of the preceding categories.
This diagnosis should be used only if the patient's mental
retardation cannot be classified more precisely under categories .0 to
.5 above.
.7 Following major psychiatric disorder
This category is for mental retardation following psychosis or other
major psychiatric disorder in early childhood when there is no evidence
of cerebral pathology. To make this diagnosis there must be good
evidence that the psychiatric disturbance was extremely severe. For
example, retarded young adults with residual schizophrenia should not
be classified here.
.8 With psycho-social (environmental) deprivation
This category is for the many cases of mental retardation with no
clinical or historical evidence of organic disease or pathology but for
which there is some history of psycho-social deprivation. Cases in this
group are classified in terms of psycho-social factors which appear to
bear some etiological relationship to the condition as follows:
Cultural-familial mental retardation. Classification here requires that
evidence of retardation be found in at least one of the parents and
in one or more siblings, presumably, because some degree of cultural
deprivation results from familial retardation. The degree of
retardation is usually mild.
Associated with environmental deprivation. An individual deprived
of normal environmental stimulation in infancy and early childhood
may prove unable to acquire the knowledge and skills required
to function normally. This kind of deprivation tends to be more
severe than that associated with familial mental retardation (q.v.).
This type of deprivation may result from severe sensory impairment,
even in an environment otherwise rich in stimulation. More rarely