Institute of Neuroscience and Department of Biology, University of Oregon, Eugene, Oregon 97403.
Institute of Neuroscience and Department of Biology, University of Oregon, Eugene, Oregon 97403
J Neurosci. 2019 May 8;39(19):3687-3697. doi: 10.1523/JNEUROSCI.2585-18.2019. Epub 2019 Mar 5.
Learned behavioral responses to sounds depend largely on the expected outcomes associated with each potential choice. Where and how the nervous system integrates expectations about reward with auditory sensory information to drive appropriate decisions is not fully understood. Using a two-alternative choice task in which the expected reward associated with each sound varied over time, we investigated potential sites along the corticostriatal pathway for the integration of sound signals, behavioral choice, and reward information in male mice. We found that auditory cortical neurons encode not only sound identity, but also the animal's choice and the expected size of reward. This influence of reward expectation on sound- and choice-related activity was further enhanced in the major striatal target of the auditory cortex: the posterior tail of the dorsal striatum. These results indicate that choice-specific information is integrated with reward signals throughout the corticostriatal pathway, potentially contributing to adaptation in sound-driven behavior. Learning and maintenance of sensory-motor associations require that neural circuits keep track of sensory stimuli, choices, and outcomes. It is not clear at what stages along the auditory sensorimotor pathway these signals are integrated to influence future behavior in response to sounds. Our results show that the activity of auditory cortical neurons and of their striatal targets encodes the animals' choices and expectation of reward, in addition to stimulus identity. These results challenge previous views of the influence of motor signals on auditory circuits and identifies potential loci for integration of task-related information necessary for updating auditory decisions in changing environments.
学习行为对声音的反应在很大程度上取决于与每个潜在选择相关的预期结果。神经系统如何将对奖励的期望与听觉感觉信息整合起来,以驱动适当的决策,目前还不完全清楚。我们使用了一种二选一的选择任务,其中与每个声音相关的预期奖励随时间变化,我们研究了雄性小鼠皮质纹状体通路中潜在的整合声音信号、行为选择和奖励信息的部位。我们发现,听觉皮层神经元不仅编码了声音的身份,还编码了动物的选择和预期的奖励大小。这种奖励预期对声音和选择相关活动的影响在前听觉皮层的主要纹状体靶点:背侧纹状体的尾部更为明显。这些结果表明,特定于选择的信息在整个皮质纹状体通路上与奖励信号整合在一起,可能有助于对声音驱动的行为进行适应。学习和维持感觉运动关联需要神经回路跟踪感觉刺激、选择和结果。目前还不清楚这些信号在听觉感觉运动通路上的哪个阶段整合,以影响对声音的未来行为。我们的结果表明,听觉皮层神经元及其纹状体靶点的活动除了刺激身份外,还编码了动物的选择和对奖励的期望。这些结果挑战了以前关于运动信号对听觉回路影响的观点,并确定了在不断变化的环境中更新听觉决策所需的与任务相关信息整合的潜在部位。