Klingberg F, Klingberg H
Paul Flechsig Institute for Brain Research, Department of Neurophysiology, Karl Marx University, Leipzig, GDR.
Biomed Biochim Acta. 1988;47(6):497-505.
Six-month-old male Long-Evans rats reproduced their preoperatively learnt active avoidance responses (CAR) in a Y-maze and in a jump test box after bilateral symmetric lesions of thalamic anterior ventral (AV) and anterior medial (AM) nuclei without significant changes. However, when the test sequence was changed in a way that transitions from high success probability (low error probability) to low success probability (high error probability) were taken into account, then problems with time limit and increased punishments were not overcome by lesioned rats. Transitions in the opposite direction were better mastered. All AV-AM rats were unable to acquire a new CAR stereotype in a W-like maze in which the first phase had a low success probability. Rats without lesions were rarely influenced by various test sequences. The lesioned rats showed purely arrest behaviour and did not develop learned helplessness in successless sessions and were transiently hyperactive in the open field test. The data support the hypothesis that the anterior thalamic nuclei as part of the Papez circuit participate in the analysis of success probability and preferent consolidation of correct responses, when stereotype behaviour has to be changed.
6个月大的雄性Long-Evans大鼠在丘脑前腹侧（AV）和前内侧（AM）核双侧对称损伤后，能在Y迷宫和跳跃测试箱中重现术前习得的主动回避反应（CAR），且无显著变化。然而，当测试顺序以考虑从高成功概率（低错误概率）到低成功概率（高错误概率）的转变的方式改变时，损伤大鼠无法克服时间限制和增加惩罚带来的问题。相反方向的转变则能更好地掌握。所有AV-AM大鼠在W型迷宫中无法习得新的CAR刻板行为，其中第一阶段的成功概率较低。未损伤的大鼠很少受到各种测试顺序的影响。损伤大鼠在无成功的实验环节中表现出纯粹的停滞行为，未出现习得性无助，且在旷场试验中短暂多动。这些数据支持以下假设：丘脑前核作为帕佩兹环路的一部分，在必须改变刻板行为时，参与成功概率的分析和正确反应的优先巩固。
