Human voice perception

We are all voice experts. First and foremost, we can produce and understand speech, and this makes us a unique species. But in addition to speech perception, we routinely extract from voices a wealth of socially-relevant information in what constitutes a more primitive, and probably more universal, non-linguistic mode of communication. Consider the following example: you are sitting in a plane, and you can hear a conversation in a foreign language in the row behind you. You do not see the speakers' faces, and you cannot understand the speech content because you do not know the language. Yet, an amazing amount of information is available to you. You can evaluate the physical characteristics of the different protagonists, including their gender, approximate age and size, and associate an identity to the different voices. You can form a good idea of the different speaker's mood and affective state, as well as more subtle cues as the perceived attractiveness or dominance of the protagonists. In brief, you can form a fairly detailed picture of the type of social interaction unfolding, which a brief glance backwards can on the occasion help refine - sometimes surprisingly so. What are the acoustical cues that carry these different types of vocal information? How does our brain process and analyse this information? Here we briefly review an emerging field and the main tools used in voice perception research.