The development of attention in the infant can be characterized by changes in overall arousal (attentiveness) and by changes in attention's effect on specific cognitive processes (e.g., stimulus orienting, spatial selection, recognition memory). These attention systems can be identified using behavioral and psychophysiological methods. The development of infant attention is thought to be closely related to changes in the neural systems underlying attention control. The recent application of cortical source analysis of event-related potentials (ERP) and structural magnetic resonance imaging (MRI) has led to the identification of some of these the neural systems.