Infants’ Understanding of Others’ Goal-Directed Actions Covaries With Speed of Encoding

Woodward (2003) reported that twelve-month-old infants interpret another’s gaze and head shift (single fixation) as goal-directed. Johnson and colleagues (2007) reported that nine-month-old infants are also able to, if they observe equifinal action-paths (multiple fixations). The current study investigated how infants' encoding speed relates to this comprehension. We tested fifty-nine 10-12 month old infants in a habituation paradigm similar to Woodward (2003), but stimuli were prerecorded videos of an actor performing a single or multiple fixations. We categorized infants' encoding speed as slow or fast based on a median split of total habituation time. Encoding speed interacted with fixation condition, in that the multiple fixations stimuli helped fast-encoders interpret the action as goal-directed but the slow-encoders only interpreted the single fixation as goal-directed. These results indicate that encoding speed is a relevant factor of infant's understanding of goal-directed actions.