Goodman Jarid, Gabriele Amanda, Packard Mark G
Department of Psychology, Institute for Neuroscience, Texas A&M University.
Department of Psychology, Texas A&M University.
Behav Neurosci. 2017 Apr;131(2):143-148. doi: 10.1037/bne0000190.
The present study examined the role of the dorsolateral striatum (DLS) in extinction behavior. Male Long-Evans rats were initially trained on the straight alley maze, in which they were reinforced to traverse a straight runway and retrieve food reward at the opposite end of the maze. After initial acquisition, animals were given extinction training using 1 of 2 distinct protocols: response extinction or latent extinction. For response extinction, the animal was released from the same starting position and had the opportunity to perform the originally reinforced approach response to the goal end of the maze, which no longer contained food. For latent extinction, the animal was confined to the original goal location without food, allowing the animal to form a new cognitive expectation (i.e., that the goal location is no longer reinforced). Immediately before response or latent extinction training, animals received bilateral intra-DLS administration of the sodium channel blocker bupivacaine or control injections of physiological saline. Results indicated that neural inactivation of the DLS with bupivacaine impaired response extinction, but did not influence latent extinction. The dissociation observed indicates that the DLS selectively mediates extinction mechanisms involving suppression of the original response, as opposed to cognitive mechanisms involving a change in expectation. (PsycINFO Database Record
本研究考察了背外侧纹状体（DLS）在消退行为中的作用。雄性Long-Evans大鼠最初在直巷迷宫中接受训练，在迷宫中它们因穿过直跑道并在迷宫另一端获取食物奖励而得到强化。初始习得后，动物使用两种不同方案中的一种进行消退训练：反应消退或潜在消退。对于反应消退，动物从相同起始位置释放，有机会对迷宫目标端做出最初强化的接近反应，但目标端不再有食物。对于潜在消退，动物被限制在没有食物的原目标位置，使动物形成新的认知预期（即目标位置不再有强化）。就在反应或潜在消退训练前，动物接受双侧DLS内注射钠通道阻滞剂布比卡因或生理盐水对照注射。结果表明，布比卡因使DLS神经失活损害了反应消退，但不影响潜在消退。观察到的这种分离表明，DLS选择性地介导涉及抑制原始反应的消退机制，而不是涉及预期改变的认知机制。（PsycINFO数据库记录
