Wenk G L
Division of Neural Systems, Memory and Aging, Arizona Research Laboratories, University of Arizona, Tucson 85724, USA.
Neurobiol Learn Mem. 1997 Mar;67(2):85-95. doi: 10.1006/nlme.1996.3757.
The nucleus basalis magnocellularis (NBM) contains a population of large cholinergic (Ch) neurons that send their axons to the entire cortical mantle, the olfactory bulbs, and the amygdala. This is the centennial anniversary of the first exact description of this nucleus by Von Kölliker, who named it in honor of its discoverer. This review will focus upon recent attempts to understand the role of the NBM Ch neurons in higher cognitive function by the use of selective lesion analyses and electrophysiological recording techniques. Behavioral deficits associated with NBM lesions produced by injections of excitatory amino acid agonists have been demonstrated in a variety of tasks. Performance decrements produced by these lesions were initially interpreted as being the result of impairments in learning and memory abilities. However, the precise role of the Ch NBM neurons in these performance deficits could not be more thoroughly investigated until it became possible to produce selective and discrete lesions by injection of the immunotoxin, IgG-192 saporin. The results of investigations using this immunotoxin supported a role for NBM Ch neurons in the performance of tasks that require selected attentional abilities rather than learning and memory per se. These lesion analysis studies suggested that the corticopetal NBM Ch system may be involved in the control of shifting attention to potentially relevant, and brief, sensory stimuli that predict a biologically relevant event, such as a food reward. Electrophysiological evidence has implicated NBM Ch cells in the control of attentional processes, as well as a role in the control and maintenance of arousal and sleep states. Electrophysiological studies also suggest that NBM Ch neurons might influence cortical EEG activity in two ways, by its direct excitatory inputs and by an indirect inhibitory projection to the thalamic reticular nucleus. Taken together with the results of histological and anatomical studies of the basal forebrain, NBM Ch cells appear to be ideally located within the basal forebrain for evaluating sensory stimuli for their level of significance, via inputs from the midbrain and limbic system, and also to modulate intrinsic cortical responsiveness appropriately in order to attend to brief, highly salient sensory stimuli.
大细胞基底核（NBM）包含一群大型胆碱能（Ch）神经元，其轴突投射至整个皮质、嗅球和杏仁核。今年是冯·克利克首次精确描述该核的一百周年，他以该核发现者的名字为其命名。本综述将聚焦于近期通过选择性损伤分析和电生理记录技术来理解NBM胆碱能神经元在高级认知功能中作用的尝试。注射兴奋性氨基酸激动剂导致的NBM损伤所产生的行为缺陷已在多种任务中得到证实。这些损伤导致的行为表现下降最初被解释为学习和记忆能力受损的结果。然而，在能够通过注射免疫毒素IgG - 192皂草素产生选择性和离散性损伤之前，无法更深入地研究胆碱能NBM神经元在这些行为缺陷中的精确作用。使用这种免疫毒素的研究结果支持了NBM胆碱能神经元在需要选择性注意力能力而非学习和记忆本身的任务表现中发挥作用。这些损伤分析研究表明，向皮质投射的NBM胆碱能系统可能参与控制将注意力转移到预测生物相关事件（如食物奖励）的潜在相关且短暂的感觉刺激上。电生理证据表明NBM胆碱能细胞参与注意力过程的控制，以及在唤醒和睡眠状态的控制与维持中发挥作用。电生理研究还表明，NBM胆碱能神经元可能通过其直接兴奋性输入以及对丘脑网状核的间接抑制性投射这两种方式影响皮质脑电图活动。结合基底前脑的组织学和解剖学研究结果，NBM胆碱能细胞似乎理想地位于基底前脑内，以便通过来自中脑和边缘系统的输入评估感觉刺激的重要程度，并相应地调节皮质的内在反应性，从而关注短暂、高度显著的感觉刺激。
