EGR2 and psychotic disorder: For instance, chronic treatment with aripiprazole induces differential gene expression of EGR1, EGR2 and EGR4 in the rat frontal cortex;67EGR1 is differentially expressed also in rat striatum after haloperidol and clozapine treatments.68 Though less studied than EGR1, expression of EGR3 is induced by several of the same stimuli of EGR1, including antipsychotic medications or drugs that induce psychosis.25, 42 Other factors that might possibly affect the EGR3 regulon is alcohol or substance use; a relationship between drug intake or withdrawal and induction of EGR genes has been reported.