Circuit directionality for motivation: Lateral accumbens-pallidum, but not pallidum-accumbens, connections regulate motivational attraction to reward cues.
Circuit directionality for motivation: Lateral accumbens-pallidum, but not pallidum-accumbens, connections regulate motivational attraction to reward cues.
复制标题
动机的回路方向性：侧伏隔-苍白球，但不是苍白球-伏隔，连接调节对奖励线索的动机吸引力。
DOI：
10.1016/j.nlm.2019.05.001
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发表时间：
2019
影响因子：
2.7
通讯作者：
Smith,KyleS
中科院分区：
文献类型：
--
作者：
Smedley,ElizabethB;DiLeo,Alyssa;Smith,KyleS
符号跟踪行为是动物与预测奖励的线索相互作用的行为，它提供了一个例子，说明如何将激励显着性归因于线索并引发动机。伏核（NAc）和腹侧苍白球（VP）是涉及线索驱动动机的两个区域。 VP 和 NAc 亚区域（包括内侧壳和核心）对于体征跟踪至关重要。此外，已知内侧壳和 VP 之间的连接参与体征跟踪和其他动机行为。 NAc 侧壳 (NAcLSh) 是 NAc 的一个独特且尚未被研究的细分，其对奖励线索获取价值的过程的贡献仍不清楚。 NAcLSh 与奖励导向行为有关，并且与 VP 具有相互联系，这表明 NAcLSh 和 VP 相互作用可能是激励显着性的重要机制。在这里，我们使用 DREADD（由设计药物独家激活的设计受体）和交叉病毒传递策略来对投射到 VP 的 NAcLSh 神经元产生偏向抑制，反之亦然。我们发现，从 NAcLSh 到 VP 的连接中断会减少体征跟踪行为，同时不会影响食物奖励的消费。相比之下，VP 到 NAcLSh 的破坏既不影响信号跟踪，也不影响奖励消耗，但确实使动物的行为发生了更大的转变，在奖励来源可用时更倾向于奖励来源。这些发现表明，NAcLSh→VP 通路在引导动物获得奖励线索方面发挥着重要作用，而 VP→NAcLSh 反向预测可能不会，而且可能会使动机行为偏向于奖励。
Sign-tracking behavior, in which animals interact with a cue that predicts reward, provides an example of how incentive salience can be attributed to cues and elicit motivation. The nucleus accumbens (NAc) and ventral pallidum (VP) are two regions involved in cue-driven motivation. The VP, and NAc subregions including the medial shell and core, are critical for sign-tracking. Further, connections between the medial shell and VP are known to participate in sign-tracking and other motivated behaviors. The NAc lateral shell (NAcLSh) is a distinct and understudied subdivision of the NAc, and its contribution to the process by which reward cues acquire value remains unclear. The NAcLSh has been implicated in reward-directed behavior, and has reciprocal connections with the VP, suggesting that NAcLSh and VP interactions could be important mechanisms for incentive salience. Here, we use DREADDs (Designer Receptors Exclusively Activated by Designer Drugs) and an intersectional viral delivery strategy to produce a biased inhibition of NAcLSh neurons projecting to the VP, and vice versa. We find that disruption of connections from NAcLSh to VP reduces sign-tracking behavior while not affecting consumption of food rewards. In contrast, VP to NAcLSh disruption affected neither sign-tracking nor reward consumption, but did produce a greater shift in animals’ behavior more towards the reward source when it was available. These findings indicate that the NAcLSh → VP pathway plays an important role in guiding animals towards reward cues, while VP → NAcLSh back-projections may not and may instead bias motivated behavior towards rewards.