Robbins T W, Evenden J L, Ksir C, Reading P, Wood S, Carli M
Psychopharmacology (Berl). 1986;90(1):72-8. doi: 10.1007/BF00172874.
A test of attentional switching was devised for the rat in which it obtained sucrose reinforcement by an appropriate nose-poke response that discriminated which of two visual events terminated first, in a specially designed chamber. The effect of mesolimbic dopamine depletion (to 20% of control values) produced by infusions of 6-hydroxydopamine (6-OHDA) into the nucleus accumbens (N. Acc) on stable discrimination was measured alone and in the presence of a range of doses of d-amphetamine (0.4-2.3 mg/kg IP). The 6-OHDA lesion of the N. Acc impaired postoperative performance transiently by reducing choice accuracy and slowing response latency. By post-operative days 12-16, however, performance recovered to control levels and was not differentially affected by a manipulation of task difficulty. d-Amphetamine produced dose-dependent performance impairments, which were antagonised by the 6-OHDA treatment. In a second group of N. Acc lesioned rats, the neuroleptic alpha-flupenthixol (0.1-1.0 mg/kg) led to fewer trials being completed and longer latencies than in the sham-operated control group. The results are discussed in terms of the possible attentional mechanisms underlying the d-amphetamine-induced disruption of performance mediated by the N. Acc and of the implications for psychopathology resulting from possible dysfunction of this region.
为大鼠设计了一种注意力转换测试，在一个特别设计的实验箱中，大鼠通过适当的鼻触反应获得蔗糖强化，该反应能区分两个视觉事件中哪个先结束。单独测量并在一系列剂量的d-苯丙胺（0.4-2.3毫克/千克腹腔注射）存在的情况下，测量向伏隔核注射6-羟基多巴胺（6-OHDA）使中脑边缘多巴胺耗竭（降至对照值的20%）对稳定辨别力的影响。伏隔核的6-OHDA损伤通过降低选择准确性和延长反应潜伏期，短暂损害了术后表现。然而，到术后第12-16天，表现恢复到对照水平，且不受任务难度操作的差异影响。d-苯丙胺产生剂量依赖性的表现损害，6-OHDA治疗可拮抗这种损害。在另一组伏隔核损伤的大鼠中，与假手术对照组相比，抗精神病药物α-氟哌噻吨（0.1-1.0毫克/千克）导致完成的试验次数减少且潜伏期延长。根据伏隔核介导的d-苯丙胺诱导的表现破坏背后可能的注意力机制以及该区域可能功能障碍对精神病理学的影响来讨论这些结果。
