Infant-directed speech (IDS) is characterized by a range of register-typical characteristics. Many of those can be objectively measured, such as acoustic-prosodic and structural-linguistic modifications. Perceived vocal affect, however, is a socio-emotional IDS characteristic and is subjectively assessed. Vocal affect goes beyond acoustic-prosodic…

The current study examined how mothers' production of four types of internal state words at multiple ages across the second year in a free play context was related to their infants' acquisition of those words. Twenty-nine mother-infant dyads were videotaped for 18 minutes during free play when infants were 13 and 17 months old. Mothers' total and…

The Mandarin resultative verb compound (RVC; e.g., "tui dao" "push fall" and "pa shang" "climb ascend") encodes complex events composed of an initiating action and resulting activity or state. This study investigated when Mandarin-speaking children acquired this language-specific device. Specifically, we…