Area-Specific Regulation of Slow Cortical Potentials

Abstract

A negative dc potential shift typically develops prior to an anticipated event or performance. These slow potentials (SPs, a typical example of which is the contingent negative variation, CNV) have been related to behavior within the frameworks of attention (e.g., Tecce 1972), preparation (e.g., Gaillard 1978; Loveless 1979), and controlled processing (e.g., Cooper et al. 1979). However, it seems still to be topic of discussion to what extent SPs represent nonspecific states of activation/arousal or preparation, or whether they rather indicate preparatory processes in a specific manner, i.e., within distinct brain regions for distinct behavioral responses. In an attempt to integrate the various findings and interpretations reported in the literature we have conceptualized negative SPs as an indicator of “cerebral potentiality” that facilitates anticipated cerebral performance (Rockstroh et al. 1982). With regard to specificity of potentiality supply it has been assumed that potentiality or processing resources are allocated to specific cortical regions or neuronal networks depending on actual as well as anticipated processing requirements (Elbert and Rockstroh 1987). From this model it follows that SPs should be generated and regulated in a specific manner, i.e., specific with respect to temporal aspects of SP generation, in that “the timing of the E-wave is related to when in time the process it reflects is needed” (Ruchkin et al. 1986), as well as area specific, in that resources are allocated to those cortical neuronal networks that will be involved in the anticipated cerebral performance.