'Attractive' Voice May Speak Volumes About Desirability

July 28, 2008— -- An appealing voice -- a warm, confident murmur that seems to emanate from the chest rather then the neck -- can be a turn-on for many of us. Now there is strong evidence that demonstrates that an "attractive" voice serves a purpose: to draw us to the most genetically fit potential mates.

In a recent study published in the Journal of Nonverbal Behavior, researchers have shown that the human voice is more than just a stand-alone trait. It's an indicator of desirable yet difficult to perceive physiological and mental strengths.

Lead researcher Susan M. Hughes of the psychology department at Albright College in Pennsylvania measured the hands, elbows, wrists and fingers of 76 men and women between the ages of 18 to 34 to take stock of their "bilateral body symmetry."

Researchers then compared the right parts to the left parts, measuring them with instruments able to detect differences barely perceptible to the naked eye.

Research has already demonstrated that those with more symmetrical bodies are often more fit, at least in the Darwinian sense. They seem to be more fertile/virile, less susceptible to illness and less likely to carry genetic anomalies.

"Symmetry is an indirect measure of developmental fitness. That is, likely to pass on your genes to the next generation," Hughes says. Surviving the assaults of womb life -- parasites, genetic bullets -- requires a certain toughness.

After researchers had parts of their subjects' bodies measured, the volunteers were asked to count from one to 10 into a voice recorder.

A total of 101 undergraduates listened to the recordings and rated the voices on a scale from 1 to 7. The traits they were asked to measure -- approachability, dominance, healthiness, honesty, intelligence, likelihood to get dates, maturity, sexiness and warmth -- have been shown to be important in mate selection.

It came as small surprise to Hughes that the people with greater "bilateral body symmetry" also had the highest-rated voices. But, interestingly enough, the correlation was evident only for certain traits.

Men who had voices that were perceived as approachable, sexy, intelligent and warm showed high body symmetry. (So much for honesty and maturity.)

As for the women, only those with voices considered approachable, sexy and "likely to get dates" showed significant body symmetry. (So much for intelligence.)

Even more interesting, perhaps, is that women with an index finger to ring finger ratio similar to the average man's ratio -- just the length of two specific fingers in relation to each other -- had voices that received high ratings for dominance and maturity.

Why?

Ratios between the ring and index finger are an indirect measure of prenatal sex hormone exposure, Hughes says.

"The index finger being shorter than ring finger is a sign of greater androgen exposure in the womb," she says. "And this is what the females tended to have who had voices rated as being more mature and dominant sounding."

No similar correlation was found in men.

Yet G.T. Manning, a well-regarded British researcher has published work that seems to indicate that there may be a correlation between hormone exposure/digit ratio and sexual orientation.

Voices also can be an indicator of other things, even though people can go to voice coaches, affect accents and do all sorts of things to change their voice quality.

Changes can be made, says Hughes, but she compares them to applying makeup.

"The sheer tonal qualities can be manipulated," she says, "but the control we have over our voices is constrained by biology."