Abstract
Two types of the so-called hippocampal arousal waves were reported in relation to the dog's behaviors. The one, hippocampal rhythmic wave-S, occurred only after sleep pattern spontaneously or by stimuli, during the appearance of which the animal kept continuously a sleeping posture but showed a few localized twichings of eyelids, conchae, vibrissae, facial muscles etc. and frequently rapid movement potentials of eyeballs. The other, hippocampal rhythmic wave-A, was seen in a short train during wakefulness, accompanying some actions, i.e. head-turning, sniffing, searching on the floor etc. The characteristics and interrelationships of these waves were discussed.
