FRIDAY, Oct. 4 (HealthDay News) -- Your voice can reveal whether the person you're talking to is a lover or a friend, a new study suggests.

The sound of people's voices is different when speaking to romantic partners compared to buddies, and such variations could potentially be used to detect infidelity, according to study author Susan Hughes, an associate professor of psychology at Albright College in Reading, Pa.

"It's not just that we change the sound of our voice, but that others can easily perceive those changes," Hughes said in a college news release.

The study included 24 people who were newly in love. They were asked to phone their romantic partners and a close same-sex friend and in both cases have a conversation asking specifically "How are you?" and "What are you doing?"

The calls were recorded and played to 80 independent listeners who judged the recordings for their sexiness, pleasantness and degree of romantic interest.

"Vocal samples directed toward romantic partners were rated as sounding more pleasant, sexier and reflecting greater romantic interest than those directed toward same-sex friends," according to the study in the October issue of the Journal of Nonverbal Behavior.

One type of analysis of the voice recordings revealed that both men and women tend to adjust their pitch to match that of their romantic partner. Women will use a lower pitch, while men will use a higher pitch.

Another type of analysis that focused on voice elements such as inflection and intonation revealed stress, nervousness and lack of confidence in the voices of participants when they were talking to their lovers. This could be due to the fact that they were still in the early stages of love, the researchers suggested in the news release.

"There was vulnerability associated with the voices of those newly in love. Perhaps people don't want to be rejected," said Hughes, an expert in evolutionary psychology and voice perception.

More information

The American Association for Marriage and Family Therapy has more about infidelity.