Abstract

Gestures are social in nature. Wundt proposed a «conception of the gesture as that which becomes later a symbol, but which is to be found in its earlier stages as a part of a social act. It is that part of the social act which serves as a stimulus to other forms involved in the same social act» (Mead G.B., 1934). Gestural theories of language have been elaborated by both philosophers and, more recently, neuroscientists. According to Merleau-Ponty, to speak is to make a gesture and we possess words in terms of their articulatory and acoustic style as one of the possible uses of our bodies. A critical contribution to clarify the gestural account of language proposed by phenomenology comes from the empirical evidence supporting the idea that language evolved from gestures. This idea is also captured by the Motor Theory of Speech Perception and Articulatory Phonology. Recent studies strongly suggest that during the gradual transition from manual gesture to speech, the social and intersubjective nature of gestural communication was maintained in the spoken language. Indeed, it has been shown that the social intention to interact with a conspecific affects not only the kinematics of social actions and communicative gestures, but also the pronunciation of words. Further, both executing and observing gestures can influence the simultaneous pronunciation of syllables/words and in particular their vocal spectra. Thus, the social value can be conveyed from manual gestures to speech, mostly through the motor components of spoken language. This may be due to a system of dual hand/mouth motor commands. Concurrently, a motor mirror mechanism may have allowed the characteristics of observed gestures to be maintained in language. As a result, both language expression and comprehension are social.