Test of two hypotheses about summation of rewarding brain stimulation.
D000818:Animals; D001921:Brain / Q000502:physiology*; D004594:Electrophysiology; D007031:Hypothalamus / Q000502:physiology; D008297:Male; D009433:Neural Inhibition; D051381:Rats; D012653:Self Stimulation / Q000502:physiology*; D013681:Tegmentum Mesencephali / Q000502:physiology; D013997:Time Factors