Postural reflexes do not fully account for postural control during skilled, purposeful movements, how ever. For example, the simple act of reaching out to grasp an object can destabilize balance unless precisely timed compensatory action is initiated before the arm extended. Thus a system needed to generate anticipa- tory responses. In addition, a wide range of automatic response patterns must be available to cope with any unexpected disturbances. Finally, because postural con trol must be integrated with voluntary movement, postural control systems must be capable of adaptive learning. Thus the current view is that postural control involves the behaviorally meaningful integration of many different neural systems, including those associated with cognition.