COMPARISON OF DEVELOPMENTAL PATTERNS OF THREE DIAGNOSTIC GROUPS OF MIDDLE GRADE AND LOW GRADE MENTAL DEFECTIVES.

The article presents a comparative study on the pattern of intellectual development of the etiological group in Mongolism in the U.S. This paper compares two equated groups of brain injured and familial mental defectives in the areas of verbal production and concrete performance. The subject of this study include middle grade or low grade defective intellectual level.