The crossroads of anticipatory attention and motor preparation. I.

This series of papers suggests that processes underlying anticipatory attention and motor preparation share a common control mechanism. Both functions are of utmost importance for an optimal adaptation to our environment. While the posterior part of the cortex is aimed at the analysis of incoming information, both from the outer world and our own body, the anterior part is involved in action and reaction. If we know when in the near future we will be confronted with relevant information, and how this has to be responded upon, modality specific sensoric and motoric information channels have to be open in order to guarantee an adequate response. The anterior and posterior parts of the cortex are activated from the thalamus and the information transmission is influenced via the reticular nucleus (RN) of the thalamus. The RN itself is under a double control: excitatory from the prefrontal cortex and inhibitory from the neostriatum. It is suggested that selection in anticipatory attention and motor preparation is realized in a comparable way via the RN. In Part I the relevant anatomical structures are described. In Part II the model for anticipatory attention and motor preparation is presented. In Part III the supporting neuropsychological evidence is presented, after which psychophysiological experiments will be discussed having lead to the formulation of the model.