Ricker Joshua M, Hatch Justin D, Powers Daniel D, Cromwell Howard Casey
J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University.
J Comp Psychol. 2016 May;130(2):174-86. doi: 10.1037/com0000034. Epub 2016 Apr 14.
Choice behavior combines discrimination between distinctive outcomes, preference for specific outcomes and relative valuation of comparable outcomes. Previous work has focused on 1 component (i.e., preference) disregarding other influential processes that might provide a more complete understanding. Animal models of choice have been explored primarily utilizing extensive training, limited freedom for multiple decisions and sparse behavioral measures constrained to a single phase of motivated action. The present study used a paradigm that combines different elements of previous methods with the goal to distinguish among components of choice and explore how well components match predictions based on risk-sensitive foraging strategies. In order to analyze discrimination and relative valuation, it was necessary to have an option that shifted and an option that remained constant. Shifting outcomes among weeks included a change in single-option outcome (0 to 1 to 2 pellets) or a change in mixed-option outcome (0 or 5 to 0 or 3 to 0 or 1 pellets). Constant outcomes among weeks were also mixed-option (0 or 3 pellets) or single-option (1 pellet). Shifting single-option outcomes among weeks led to better discrimination, more robust preference and significant incentive contrast effects for the alternative outcome. Shifting multioptions altered choice components and led to dissociations among discrimination, preference, and reduced contrast effects. During extinction, all components were impacted with the greatest deficits during the shifting mixed-option outcome sessions. Results suggest choice behavior can be optimized for 1 component but suboptimal for others depending upon the complexity of alterations in outcome value between options. (PsycINFO Database Record
选择行为包括对不同结果的辨别、对特定结果的偏好以及对可比结果的相对估值。以往的研究主要集中在一个组成部分（即偏好），而忽略了其他可能提供更完整理解的影响过程。选择的动物模型主要是通过广泛的训练、限制多次决策的自由度以及将行为测量稀疏地限制在动机行动的单一阶段来探索的。本研究使用了一种将先前方法的不同元素结合起来的范式，目的是区分选择的各个组成部分，并探索这些组成部分与基于风险敏感觅食策略的预测的匹配程度。为了分析辨别和相对估值，必须有一个变化的选项和一个保持不变的选项。几周内结果的变化包括单选项结果的变化（从0到1到2颗颗粒）或混合选项结果的变化（从0或5到0或3到0或1颗颗粒）。几周内恒定的结果也是混合选项（0或3颗颗粒）或单选项（1颗颗粒）。几周内单选项结果的变化导致了更好的辨别、更强的偏好以及对替代结果的显著激励对比效应。多选项的变化改变了选择的组成部分，并导致辨别、偏好之间的分离以及对比效应的降低。在消退过程中，所有组成部分都受到了影响，在变化的混合选项结果阶段缺陷最大。结果表明，根据选项之间结果值变化的复杂性，选择行为可以针对一个组成部分进行优化，但对其他组成部分则次优。（PsycINFO数据库记录
