The phrase "music to my ears" may take on a new meaning if researchers are right. For many years common wisdom has dictated that warning messages played in high task-loading environments be recorded by a woman. Now there's a growing body of scientific information that explains in part why a woman's voice seems to work better to gain attention. Scientists at the University of Sheffield studied the differences in the way the male brain interprets male and female voices. The study sheds new light on the way the brain processes voices to produce an 'auditory face' that allows people to determine aspects of someone's physical appearance based solely on the way they sound.
The paper, published online in NeuroImage, describes how scientists studied brain scans of 12 male subjects while they listened to male and female voices. It found startling differences in the way that the brain interprets the two sounds, with female voices causing activity in the auditory section of the brain and the male voice sparking activity in the 'mind's eye' at the back of the brain. Earlier research led by Dr Joseph Lurito, of Indiana University showed women use both sides of their brain to listen, while men only use the left side. Studies suggest women can handle two conversations at once.
Dr Michael Hunter, of the Department of Psychiatry and Division of Genomic Medicine at the University of Sheffield, and co-author of the Sheffield study commented, "Voices allow the brain to determine various factors about a person's appearance, including their sex, size and age. It is much more complex than most people think and is an extremely important tool for determining someone's identity without having to see them."
The study determined that the female voice is actually more complex than the male voice, due to differences in the size and shape of the vocal cords and larynx between women and men. According to the study, women have greater natural 'melody in their voices.
When men hear a male voice the part of the brain that processes the information is towards the back of the brain and is colloquially known as the 'mind's eye'. This is the part of the brain where people compare their experiences to themselves, so the man is comparing his own voice to the new voice to determine gender. Processing a woman's voice activates parts of the brain associated with music to a higher level of activity.
According to Dr. Hunter, people who hear hallucinatory voices usually hear male voices. Psychiatrists believe that these auditory hallucinations are caused when the brain spontaneously activates, creating a false perception of a voice. The reason these voices are usually male could be explained by the fact that the female voice is so much more complex that the brain would find it much harder to create a false female voice accurately than a false male voice. This research could also explain why female voices are considered to be more clear than male voices. The phenomenon could be linked to the fact that female voices are interpreted in the auditory part of the brain, and are therefore more easily decoded.
The Sheffield study used a panel of men due to the differences in how men and women process sounds. Women use both halves of their brains while men employ primarily the left side. Scientists explained their selection of men for the initial study observing that they wanted to start with the simpler processing model first. A later study will use women to understand the more complex processing model.