Infants' perceptions of constraints on object motion as a function of object shape.

Three studies examined young infants' ability to distinguish between expected and unexpected motion of objects based on their shape. Using a preferential-looking paradigm, 8- and 12-month-old infants' looking time towards expected and unexpected motion displays of familiar, everyday objects (e.g., balls and cubes) was examined. Experiment 1 demonstrated that two factors drive infants' preferential fixations of object motion displays. Both 8- and 12-month-olds displayed a tendency to look at rotating information over non-rotating, stationary visual information. In contrast, only 12-month-olds showed a tendency to look at object motions that were inconsistent or "unexpected" based on shape. After controlling for the preference for more complex (rolling) by adding rolling motion to both displays (Experiment 2), 12-month-olds' ability to distinguish between expected and unexpected motion displays was facilitated. Experiment 3 provided a control by demonstrating that the preference for the unexpected object motion was not due to any other motion properties of the objects. Overall, these results indicate that 12-month-old infants have the ability to recognize the role that object shape plays in constraining object motion, which has important theoretical implications for the development of object perception.

Playing a first-person shooter video game induces neuroplastic change.

Playing a first-person shooter (FPS) video game alters the neural processes that support spatial selective attention. Our experiment establishes a causal relationship between playing an FPS game and neuroplastic change. Twenty-five participants completed an attentional visual field task while we measured ERPs before and after playing an FPS video game for a cumulative total of 10 hr. Early visual ERPs sensitive to bottom-up attentional processes were little affected by video game playing for only 10 hr. However, participants who played the FPS video game and also showed the greatest improvement on the attentional visual field task displayed increased amplitudes in the later visual ERPs. These potentials are thought to index top-down enhancement of spatial selective attention via increased inhibition of distractors. Individual variations in learning were observed, and these differences show that not all video game players benefit equally, either behaviorally or in terms of neural change.