Dimensions of premorbid functioning in schizophrenia: a review of neuromotor, cognitive, social, and behavioral domains.

After a brief discussion of methods for studying the premorbid period in schizophrenia, the authors review relevant experimental literature to assess the validity of current theories. A critical review is provided that includes representative empirical investigations on premorbid functioning in schizophrenia in the domains of neuromotor, intellectual, academic, cognitive, social, emotional, and behavioral functioning. Limitations of past research, such as lack of specificity to schizophrenia populations, high incidences of false positives, questionable definitions of the premorbid period, inconsistent measures of premorbid functioning, and problems with the current method of DSM classification are discussed. Alternative approaches to studying early functioning in schizophrenia are highlighted.