Changes in Central EEG Activity in relation to Voluntary Movement. I. Normal Subjects

Abstract

This chapter discusses changes in central electroencephalography (EEG) activity in relation to voluntary movement. In the central region various changes in the EEG activity can be recorded before and during a self-paced voluntary movement. These changes can be found either in the intrinsic EEG and here especially in the rhythmic activity within the alpha band in form of a movement-related amplitude reduction (desynchronization) or in the slow negative potential shift known as Bereitschaftspotential. Beside this, different macropotentials—for example, the motor cortex potential, are also generated. The chapter introduces the results of a study on 20 normal subjects, of the behaviour of central mu activity and negative potential shift preceding and during voluntary pressing of a rubber ball. The reason for the use of a rubber ball, of about 5 cm diameter, for the execution of a voluntary movement is that the same ball is to be used also in a study on patients with cerebral hemispheric lesions (expansive or infarct).