Satiation-induced avoidance responses to betaine. (A) Partial satiation raised feeding thresholds significantly over presatiation measures. (B) Partial satiation increased the frequency of avoidance responses (withdrawal and turns) to the feeding stimulus during threshold measures. *, P < 0.0001, two-tailed paired Wilcoxon signed rank test. **, P < 0.006; ***, P < 0.002; two-sided values, Fisher's exact tests.