[Relationship between attention and mu rhythms in the cat and the monkey (author's transl)]

Recording from the cat and monkey parietal cortex reveals the existence of three categories of spontaneous rhythmic activities, with different frequencies, that have the same reactivity and localization as the mu rhythm in man. Each of these rhythms corresponds to a different level of attention and can be preferentially determined through placing the subject in a given situation. The fastest rhythms are observed when the subject displays an attentive behaviour toward a significant target, while those of intermediate frequency are seen during a period of expectancy (like watching a mouse-hole). The slowest rhythms occur when the subject does not show interest to its surrounding. A hypothesis is proposed that mu rhythms are involved in the neurophysiological mechanisms of attention.