Regional brain c-fos activation associated with penile erection and other symptoms induced by the spider toxin Tx2-6

► Tx2-6 is a neurotoxin from Phoneutria nigriventer venom that induces penile erection. ► Induction of c-fos expression in brain during intoxication was mapped. ► Brain areas correlate better to a stress response than to erction-related regions. ► There is a poor correlation with convulsion-related areas. ► Intracerebral injection of the toxin failed to induce penile erection.