Modification of spontaneous ECoG and behavior in cat by monoamine precursors.

The effects of increasing the brain monoamine content on the three types of localized rhythms identified in somatic area I ("mu-type rhythms") were studied in freely moving cats. Increases in brain monoamines (catecholamines and serotonin) were produced by injecting L-Dopa and 5-HTP, L-tyrosine, L-tryptophan and tryptamine were also tested. It is concluded that the two subsets of rhythms, one accompanying high levels of alertness and vigilance and the other appearing during quiet wakefulness, are related to the catecholaminergic systems, while those characterizing drowsiness seem to be controlled by a serotoninergic system. The latter, however, is distinct from that controlling slow sleep.