U.S. scientists say they've determined people spontaneously use a system of "verbal gestures" when they speak.
University of Chicago scientists say the previously uninvestigated form of communication dubbed "analog acoustic expression" is a kind of verbal gesturing that expands people's capacity to communicate and typically occurs with little intention on the part of the speaker.
Although researchers have long been aware people modulate their speech, psychology Professor Howard Nusbaum said scientists had assumed some modulation was intentional, designed to emphasize points or communicate emotion.
The new discovery, Nusbaum said, is the first experimental evidence showing people unconsciously modulate their voices to provide an additional channel of expression.
"Someone will raise his voice slightly at the end of the sentence when saying, 'the stock market is going up' or lower it when saying 'the stock market is going down,'" said Nusbaum, a co-author of the study and chairman of the university's psychology department. Such modulations also make telephone conversations and words spoken on the radio more comprehensible, he added.
The research appears in the current issue of the Journal of Memory and Language.
Copyright 2006 by United Press International