Bush also using the MMIP in normal males and females, examined the relationship between psychoticism in males and defensive rigidity in female the stroop significantly correlated with the psychoticism index for female (p= 01) and defensive rigidity for male (P=01)killian also found that of 19 cognitive measures only the stroop inference score successfully discriminated between those schizophrenic and depressed patients who responded to psychotropic drugs from those who were classified as non responders.