Generative character of perception: a neural architecture for sensorimotoranticipation

The basic idea of our anticipatory approach to perception is to avoid the c ommon separation of perception and generation of behavior and to fuse both aspects into a consistent neural process. Our approach tries to explain the phenomenon of perception, in particular, of perception at the level of sen sorimotor intelligence, from a behavior-oriented point of view. Perception is assumed to be a generative process of anticipating the course of events resulting from alternative sequences of hypothetically executed actions. By means of this sensorimotor anticipation, it is possible to characterize a visual scenery immediately in categories of behavior, i.e. by a set of acti ons which describe possible methods of interaction with the objects in the environment. Thus, the competence to perceive a complex situation can be un derstood as the capability to anticipate the course of events caused by dif ferent action sequences. Starting from an abstract description of anticipat ory perception and the essential biological evidence for internal simulatio n, we present two biologically motivated computational models that are able to anticipate and evaluate hypothetically sensorimotor sequences. Both mod els consider functional aspects of those cortical and subcortical systems t hat are assumed to be involved in the process of sensory prediction and sen sorimotor control. Our first approach, the Model for Anticipation based on Sensory IMagination (MASIM), realizes a sequential search in sensorimotor s pace using a simple model of lateral cerebellum as sensory predictor. We de monstrate the efficiency of this model approach in the light of visually gu ided local navigation behaviors of a mobile system. The second approach, th e Model for Anticipation based on Cortical Representations (MACOR), is actu ally still at a conceptual level of realization. We postulate that this mod el allows a completely parallel search at the neocortical level using assem blies of spiking neurons for grouping, separation, and selection of sensori motor sequences. Both models are intended as general schemes for anticipati on based perception at the level of sensorimotor intelligence. (C) 1999 Els evier Science Ltd. All rights reserved.