Brasted P J, Döbrössy M D, Robbins T W, Dunnett S B
MRC Cambridge Centre for Brain Repair, University of Cambridge, UK.
Brain Res Bull. 1998 Aug;46(6):487-93. doi: 10.1016/s0361-9230(98)00044-6.
The dorsal striatum plays a crucial role in mediating voluntary movement. Excitotoxic striatal lesions in rats have previously been shown to impair the initiation but not the execution of movement in a choice reaction time task in an automated lateralised nose-poke apparatus (the "nine-hole box"). Conversely, when a conceptually similar reaction time task has been applied in a conventional operant chamber (or "Skinner box"), striatal lesions have been seen to impair the execution rather than the initiation of the lateralised movement. The present study was undertaken to compare directly these two results by training the same group of rats to perform a choice reaction time task in the two chambers and then comparing the effects of a unilateral excitotoxic striatal lesion in both chambers in parallel. Particular attention was paid to adopting similar parameters and contingencies in the control of the task in the two test chambers. After striatal lesions, the rats showed predominantly contralateral impairments in both tasks. However, they showed a deficit in reaction time in the nine-hole box but an apparent deficit in response execution in the Skinner box. This finding confirms the previous studies and indicates that differences in outcome are not simply attributable to procedural differences in the lesions, training conditions or tasks parameters. Rather, the pattern of reaction time deficit after striatal lesions depends critically on the apparatus used and the precise response requirements for each task.
背侧纹状体在介导自主运动中起着关键作用。先前的研究表明，大鼠的兴奋性毒性纹状体损伤会损害在自动侧向鼻戳装置（“九孔箱”）中进行的选择反应时任务中的运动起始，但不会损害运动执行。相反，当在传统的操作性条件反射箱（或“斯金纳箱”）中应用概念上类似的反应时任务时，纹状体损伤被发现会损害侧向运动的执行而非起始。本研究旨在通过训练同一组大鼠在两个箱中执行选择反应时任务，然后并行比较两个箱中单侧兴奋性毒性纹状体损伤的效果，直接比较这两个结果。在两个测试箱中控制任务时，特别注意采用相似的参数和意外情况。纹状体损伤后，大鼠在两项任务中主要表现为对侧功能障碍。然而，它们在九孔箱中反应时出现缺陷，而在斯金纳箱中反应执行明显出现缺陷。这一发现证实了先前的研究，并表明结果的差异并非仅仅归因于损伤、训练条件或任务参数的程序差异。相反，纹状体损伤后的反应时缺陷模式关键取决于所使用的装置以及每项任务的确切反应要求。
