Mediavilla C, Molina F, Puerto A
Departamento de Psicología Experimental y Fisiología del Comportamiento, Universidad de Granada, Spain.
Exp Brain Res. 2000 Oct;134(4):497-505. doi: 10.1007/s002210000497.
The purpose of this study was to examine the role of the external lateral parabrachial subnucleus (PBNLe) in two different taste aversion learning (TAL) procedures. For the first, short-term (concurrent) TAL, two different-flavored stimuli were presented at the same time, one associated with simultaneous intragastric administration of an aversive product, hypertonic NaCl, and the other with saline. In the second, long-term (sequential/delayed) TAL, each gustatory stimulus was presented every other day and the intragastric products LiCl and saline were administered after a 15-min delay. Electrolytic lesions in the PBNLe blocked acquisition of concurrent TAL, in which the vagal visceral information is critical. But the same lesions failed to interrupt sequential TAL. This result was independent of the order in which the two tasks (concurrent and sequential) were presented. However, as found by other authors, the latter type of learning was impaired in the presence of larger lesions in this same area. This supports the existence of sensory information needed to establish sequential TAL in other subnuclei of the parabrachial complex. The results of these experiments suggest that the different modalities of TAL are anatomically specific.
本研究的目的是考察外侧臂旁核外侧亚核（PBNLe）在两种不同的味觉厌恶学习（TAL）程序中的作用。对于第一种，即短期（同时性）TAL，同时呈现两种不同味道的刺激，一种与同时胃内注射厌恶剂高渗氯化钠相关，另一种与生理盐水相关。对于第二种，即长期（相继性/延迟性）TAL，每隔一天呈现每种味觉刺激，并在延迟15分钟后胃内注射氯化锂和生理盐水。PBNLe的电解损伤阻断了同时性TAL的习得，在这种情况下迷走神经内脏信息至关重要。但同样的损伤未能中断相继性TAL。这一结果与两项任务（同时性和相继性）呈现的顺序无关。然而，正如其他作者所发现的，在该区域存在较大损伤时，后一种学习类型会受到损害。这支持了在臂旁复合体的其他亚核中存在建立相继性TAL所需的感觉信息。这些实验结果表明，TAL的不同模式在解剖学上具有特异性。
