Modulation of Maximum Pitch in the Speech of Caregivers Addressing Their 18- to 24-Month-Old Children Corresponds to Objects Vertical Position

There are close relationships between vertical positions in space and auditory experiences of fundamental frequency (F0), which even very young children seem to use. Like adults, they associate higher or rising F0 values with upper positions in space and vice versa for lower or falling F0 values. Here, we tested whether caregivers’ speech capitalizes on these associations to guide the attention of very young children (18 to 24 months). Together with their child, caregivers saw four different objects (in the corners of a computer screen). Caregivers produced standardized sentences (e.g., “Look at the hat.”). We observed a significantly increased maximum F0 (but no differences in mean or minimum F0) at the onset of the utterance when the to be named object appeared at an upper position compared to the same object at a lower position. Furthermore, exploratory analyses of F0 dynamics of caregivers’ utterances indicated that the higher F0 maximum was part of a more prominent F0 increase for objects appearing at an upper compared to a lower position. Adults without a child present and less experience in interacting with children did not show systematic pitch modulation when addressing an imagined child in the same study set-up. Thus, caregivers appear to systematically modulate F0 dynamics to provide an effective language environment when they are interacting with their child.