No anticipation-no action: the role of anticipation in action and perception.

This paper reviews psychophysical evidence for the existence and the nature of two types of anticipation in goal-oriented action. The first one relates to attained changes of the perceptual world, thus to action goals. These anticipations determine appropriate motor output. We argue that goal codes do not only serve as a reference unit, against which currently produced behavioral effects are compared. Rather voluntary actions appear to be planned literally in terms of intended behavioral effects. The second type of anticipation relates to the environmental conditions that have to be met to bring an intended effect into being. These anticipations serve to trigger selected actions, when appropriate execution conditions are encountered. Altogether, the behavioral evidence portrays a remarkable automaticity of goal-oriented action. Once a goal exists (wherever it might come from), corresponding efferent output is generated and executed under appropriate conditions.