Pre-exposure interferes with perceptual learning for ambiguous stimuli
Pre-exposure interferes with perceptual learning for ambiguous stimuli
复制标题
预暴露会干扰对模糊刺激的感知学习
DOI：
10.1167/10.7.1140
复制
发表时间：
2010
影响因子：
1.8
通讯作者：
B. Backus
中科院分区：
文献类型：
--
作者：
L. Dam;M. Ernst;B. Backus
对双稳态刺激的感知受到该刺激的先前陈述的影响。这样的影响可能是长期的：例如，依赖位置的习得偏见可能会持续数天，而扭转这些偏见需要广泛的再培训(海江等人，2006年)。因此，训练的有效性可能会受到预先暴露于模棱两可的刺激的影响。在这里，我们调查了预暴露在学习位置依赖的知觉偏差中的作用。我们使用旋转Necker立方体作为双稳态刺激，既可以呈现在注视的上方，也可以呈现在注视下方。在训练试验中，额外的线索(双目视差和遮挡)消除了立方体旋转方向的歧义。在测试试验中，旋转立方体没有消除歧义的线索。受试者报告立方体的正面和一个移动点是朝着相同的方向还是相反的方向移动。受试者收到了关于他们回答的正确性的反馈。在350次训练试验中，受试者被暴露在立方体上方和下方固定位置的不同旋转方向下。休息5分钟后，进行后测(80个测试试验)。单独的受试者要么直接开始训练，要么在预测试(80次测试)中预先暴露于模棱两可的刺激。在83%的测试后试验中，立即开始训练的受试者平均感觉到立方体在两个位置沿着训练的方向旋转，重复了之前的结果。然而，对于暴露前的受试者，在后测中，与训练的知觉-位置偶然性的一致性只有58%。在控制条件下，我们使用消除歧义的试验来模拟前测，并在最初向受试者呈现与他们随后在训练期间暴露的相反的偶然性。测试后的一致性与训练的偶然性为78%。这表明，暴露前的干扰不一定取决于最初的知觉历史，这表明测试和训练试验之间存在根本差异。
The perception of a bistable stimulus is influenced by prior presentations of that stimulus. Such effects can be long lasting: eg position-dependent learned biases can persist for days, and reversing them requires extensive retraining (Haijiang et al., 2006). The effectiveness of training may therefore be influenced by pre-exposure to the ambiguous stimulus. Here we investigate the role of pre-exposure for learning a position dependent perceptual bias. We used rotating Necker cubes as the bistable stimuli that could be presented either above or below fixation. On training trials, additional cues (binocular disparity and occlusion) disambiguated the rotation direction for the cube. On test trials the rotating cube was presented without disambiguation cues. Subjects reported whether the front face of the cube and a moving dot moved in the same or opposite directions. Subjects received feedback about the correctness of their response. Using 350 training trials, subjects were exposed to different rotation directions for the above and below fixation locations of the cube. Following a 5-minute break a post-test (80 test trials) was performed. Separate subjects either directly started with the training, or were pre-exposed to the ambiguous stimulus in a pre-test (80 test trials). Subjects starting the training immediately, on average perceived the cube to be rotating in the trained direction for both locations on 83% of the post-test trials, replicating previous results. However, for the pre-exposed subjects, consistency with the trained percept-location contingency was only 58% in the post-test. In control conditions we simulated the pre-test using disambiguated trials and initially presented subjects with the reversed contingency than that which they would subsequently be exposed to during training. Post-test consistency with the trained contingency was 78%. This shows that the pre-exposure interference does not necessarily depend on the initial perceptual history, suggesting a fundamental difference between test and training trials.