There is uncertainty regarding the onset timing of the cognitive deficiencies of schizophrenia. We investigated whether conversion to psychosis and/or olanzapine altered the neuropsychological course of subjects within the first-ever double blind medication study of the putative schizophrenia first episode prodrome.

Hawkins KA, Keefe RSE, Christensen B, Addington J, Woods SW, Callahan J, Zipursky RB, Perkins DO, Tohen M, Breier A, McGlashan TH. Neuropsychological course in the prodrome and first episode of psychosis:  Findings from the PRIME North America Double Blind Treatment Study.  Schizophrenia Research, 2008; 105(1-3): 1-9.