Kotchoubey B I, Grözinger B, End H, Kornhuber A, Kornhuber H H
Department of Neurophysiology, University of Ulm, Germany.
Arch Ital Biol. 1995 Mar;133(2):99-115.
18 healthy right-handed subjects had to predict one of two random non-equiprobable events by pressing one of two buttons with the right index finger. Each trial was preceded by a cue that increased the probability of the corresponding event in comparison to its overall probability. The Bereitschaftspotential (BP) before an action and the stimulus-preceding negativity (SPN) between the action and the event presentation were recorded. The subjects were subdivided into groups according to their tendency to follow the cue or to reject it. Cue rejection provided in the present situation a larger final gain than cue acceptance. Those subjects who used the former strategy were characterized by a local BP increase over the right parietal cortex, when a low-probable cue was presented. Their SPN amplitude was relatively small, but it increased substantially after a low-probable cue. Subjects who tended to follow the cue had a very large BP amplitude over the projection area and at vertex. Their SPN was overall large, regardless of condition. Peculiarities of the potentials recorded in these subjects are thought to relate to their desire to minimize errors.
18名健康的右利手受试者需要用右手食指按下两个按钮之一，来预测两个随机的非等概率事件中的一个。每次试验之前都会有一个提示，与该事件的总体概率相比，这个提示会增加相应事件发生的概率。记录动作之前的准备电位（BP）以及动作和事件呈现之间的刺激前负波（SPN）。根据受试者遵循或拒绝提示的倾向将他们分成不同的组。在当前情况下，拒绝提示比接受提示能带来更大的最终收益。那些采用前一种策略的受试者的特征是，当呈现低概率提示时，右侧顶叶皮质上方会出现局部BP增加。他们的SPN振幅相对较小，但在出现低概率提示后会大幅增加。倾向于遵循提示的受试者在投射区域和头顶处有非常大的BP振幅。无论处于何种情况，他们的SPN总体上都很大。这些受试者记录到的电位特征被认为与他们将错误最小化的愿望有关。
