Effects upon the hunger drive of periods of starvation lasting up to 32 days were noted. Although weight-loss and speed of attack of food increased throughout this period, the amount of gross motor activity remained constant, and the amount of subsequent food intake reached a maximum after 4-8 days' starvation. A moving stimulus generally facilitated feeding behavior, and after long periods of starvation, odor cues alone often elicited feeding responses. (PsycINFO Database Record (c) 2006 APA, all rights reserved)