Final answer:
Causal evidence from rats indicates that choices are modulated by differences in behavior, rather than motivation. For example, male rats may still seek receptive females even if they cannot engage in sexual behavior.
Step-by-step explanation:
Causal evidence from rats indicates that choices are modulated by differences in behavior, rather than motivation. For example, research has shown that male rats exhibit different patterns of sexual behavior and motivation. Even if a male rat cannot engage in sexual behavior, it may still seek receptive females, suggesting that the ability to engage in sexual behavior and the motivation to do so are mediated by different systems in the brain (Everett, 1990).