In this edition of the new Dr Drew show "Strictly sex" on the Discovery Health Channel we learn that straight men (even the non-homophobic ones) have a primal yet subconcious "threat response" in the brain when shown images of other naked men. Threat response similar to that of seeing a snake or a vicious animal. Women on the other hand do not feel threatened by other naked women.

This is a result of a study done in Atlanta using MRI to monitor the brain while showing test subjects a sequence of 200 photographs, some of sexual nature. This study is only for heterosexual couples so it is not known if gay men have a "threat response" to other naked men ;-) But there is a similar study done in Germany for same sex couples.