It seems possible, therefore, that these events specially highlight path information in some way.
One potential way that directed motion events might highlight the path is the fact that the path always
comes first; by definition, the goal is the end of the event and the path must precede it. This
explanation, however, seems doubtful. Across the studies looking at children’s understanding of goals,
it is always the case that processes, paths, and means precede the goal; this follows logically from the
fact that causes precede effects. If precedence were the root cause of the current path bias, the literature
would be rife with process biases in all sorts of situations instead of the goal biases more commonly
found. Moreover, there is a way to explicitly test this possibility with directed motion events by
using source objects instead of goal objects (cf. Lakusta, Wagner, O’Hearn, & Landau, 2007). Instead of
modeling an action path to a specific goal object, one could model a doll starting at a specific source
object and then moving along an action path (stopping at the end of the trajectory but not at a specific
object); thus, source precedes path. If precedence were critical, we would expect the path bias to disappear
in favor of a source bias. Preliminary data from a study of just this type do not appear to show
such a bias; indeed, the path bias still seems to dominate children’s responses.