The Brain from Planet Arous is a 1957 science fiction film about alien possession. There's actually more than one brain from Planet Arous. It stars John Agar (Zontar, the Thing from Venus; Journey to the Seventh Planet; Tarantula; Mole People).
The 50's may be the hey-day of sexism. A man actually says, "Don't worry your pretty little head about it," in this one. This may be the most sensationalistic of the films I've seen so far. The alien brain causes homicide, lots of pain, rudeness, and turns perfectly normal scientists into power-mad smarmy sex-crazed sleaze-bags. With silver eyes. And then it ends with a kiss. What a disaster!
Googlevideo has it online:
Moria says it "exerts a lurid fascination". 1000 Misspent Hours gives it negative 4 stars (never a good sign).