ABSTRACT
Spoken language encodes two different sources of information. First, it carries linguistic information about the symbolic content of the talker's intended message. The second type of information carried in the speech stream is often termed paralinguistic, extralinguistic, or indexical. Speech is generated by a speaker's larynx and supralaryngeal vocal tract. The vocal tract, which extends from the larynx through the throat and mouth to the lips, acts as an acoustic filter, enhancing certain resonance frequencies (formants) and attenuating others. Behavioral and neural studies on the perceptual processing of speech illustrate its bipartite nature. Neural studies of voice identification and discrimination reveal that characteristics of the voice are processed in brain areas that are distinct from those that process the linguistic properties of the speech signal. In the linguistic task, listeners were asked to press a button every time they heard a specific target word.
