Twelve-month-olds' vocal production during pointing in naturalistic interactions: sensitivity to parents' attention and responses.

There have been many rich, naturalistic studies documenting prelinguistic communicative abilities that suggest that the ntegration of alternating eye gaze, vocal behaviors, and nonverbal gestures are indicative of intentional communication (e.g., ates, Camaioni, & Volterra, 1975; Bates, Benigni, Bretherton, Camaioni, & Volterra, 1979; Dore, 1974; Ninio & Bruner, 1978; revarthen & Hubley, 1978). Many observational studies have noted the increase in pointing and concurrent vocalizations rom the age of 12 months into the 2nd year, primarily during the acquisition of first words and later language abilities e.g., Bakeman & Adamson, 1986; Butcher & Goldin-Meadow, 2000; Carpenter et al., 1998; Goldin-Meadow, 1998; Masur, 983; Murphy, 1977); however, some studies have also documented gestures with concurrent prelinguistic vocalizations in ommunicative interactions prior to the acquisition of first words (Bates, 1976; Franco & Butterworth, 1996; Leroy, Mathiot, Morgenstern, 2009; Messinger & Fogel, 1998). Although there are many studies that document gestures and co-occurring ocalizations, few have examined the potential intentional use of communicative behaviors, particularly vocalizations, in ocial interactions (but see Camaioni, 1992; Franco & Butterworth, 1996). There has been an increase in research to investigate whether infants point with the intent to communicate or not. esearchers suggest that infants point initially for the self, without communicative intent, yet parents respond to infants’ ointing as if it was communicative (Carpendale & Lewis, 2004; see also Iverson & Thal, 1998). Similarly, researchers have uggested that communicative pointing may emerge out of initially non-communicative pointing and can be identified ased on whether or not infants alternate eye gaze to their parent and a target when they point versus pointing without ye gaze alternation (Desrochers, Morissette, & Ricard, 1995; Franco & Butterworth, 1996). Recent experimental studies in hich a social partner’s attention and response to an infant’s point are manipulated have helped to reveal the behaviors hat are indicative of communicative pointing. For example, when adults did not share infants’ interests or misidentified heir interests, infants pointed repeatedly and looked at adults more compared to when adults responded with interest and