Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, 4401 University Dr. W, Lethbridge, AB T1K 3M4, Canada.
eNeuro. 2018 Jan 8;4(6). doi: 10.1523/ENEURO.0437-17.2017. eCollection 2017 Nov-Dec.
Animals quickly learn to approach sources of food. Here, we report on a form of approach in which rats made volitional orofacial contact with inactive feeders between trials of a self-paced operant task. This extraneous feeder sampling (EFS) was never reinforced and therefore imposed an opportunity and effort cost. EFS decreased during initial training but persisted thereafter. The relative rate of EFS to operant responding increased with novel changes to the operant chamber, reward devaluation by prefeeding, or lesions to the dorsolateral striatum. We speculate that this may function to increase exploration when the task is uncertain (early in learning or introduction of novel apparatus components), when the opportunity cost is low, or when the learned sensorimotor solution is compromised. Moreover, EFS strongly affected subsequent choices by triggering a lose-shift response away from the sampled feeder, even though it occurred outside of the trial context. This indicates that at least some behaviors occurring between trials impact future behaviors and should be considered in decision-making studies.
动物很快就学会了接近食物源。在这里，我们报告了一种接近方式，即在一项自我调节操作性任务的试验之间，大鼠自愿地进行口面部接触到不活跃的喂食器。这种额外的喂食器采样（EFS）从未得到强化，因此会产生机会和努力成本。EFS 在初始训练期间减少，但此后仍持续存在。EFS 与操作性反应的相对速率随着操作性室的新变化、预喂食导致的奖励贬值或背外侧纹状体的损伤而增加。我们推测，当任务不确定（学习早期或引入新仪器组件时）、机会成本低或所学的感觉运动解决方案受到影响时，这可能有助于增加探索。此外，EFS 通过触发从采样喂食器转移的失去-转移反应强烈影响随后的选择，即使它发生在试验情境之外。这表明，至少一些在试验之间发生的行为会影响未来的行为，并且应该在决策研究中加以考虑。
