FRIDAY, May 20 (HealthDay News) -- For the average listener, the vowel sounds in an unfamiliar voice quickly give away the speaker's sexual orientation, a new study finds."I'm not sure what exactly the listeners are responding to in the vowel," study lead author Erik C. Tracy, a cognitive psychologist at Ohio State University, said in a news release from the American Institute of Physics. "Other researchers have done various acoustic analyses to understand why gay and heterosexual men produce vowels differently. Whatever this difference is, it seems that listeners are using it to make this sexual orientation decision." When hearing...