Fig 2. Dietary effects on impulsive choice.

A) Mean proportion of LL choices overall and for each group when rats were tested on their designated diets versus when tested off the diets. HF and HS rats became less SS preferring after removal from the diet compared to C rats (ps < .001). B) Mean proportion of LL choices as a function of SS delay for each group when rats were tested on their designated diets. HF and HS rats made more impulsive choices, indicating a greater bias for immediacy than C rats (ps = .021 and .003, respectively). HF and HS rats also had steeper slopes than C rats (ps < .001), indicating heightened sensitivity to delay. C) Mean proportion of LL choices as a function of SS delay for each group when rats were tested off their designated diets. There were no significant differences in bias, but HF and HS rats had steeper slopes than C rats (p = .016 and p < .001, respectively). D) Mean proportion of LL choices for Group HF as a function of SS delay when they were on versus off the diet. HF rats made fewer impulsive choices and displayed lower slopes off the diet (ps < .001). E) Mean proportion of LL choices for Group HS as a function of SS delay when they were on versus off the diet. HS rats made fewer impulsive choices and displayed lower slopes off the diet (ps < .001). F) Mean proportion of LL choices for Group C as a function of SS delay when they were on versus off the diet. C rats showed no differences in impulsive choice on and off the diet (p = .761), but they had lower slopes off the diet (p < .001). Errors bars depict ± the SE of the model prediction.