Probabilistic classification learning in amnesia.
Probabilistic classification learning in amnesia.
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DOI：
10.1101/lm.1.2.106
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发表时间：
1994-07
影响因子：
2
通讯作者：
B. Knowlton;L. Squire;M. Gluck
中科院分区：
文献类型：
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作者：
B. Knowlton;L. Squire;M. Gluck
糖尿病患者和对照受试者参加了一项概率分类学习的研究。在三项任务中，四种不同的线索分别与两种结果之一相关。在每次试验中，这些线索可以单独出现，也可以与其他线索组合出现，受试者选择他们认为正确的结果。每次试验后都提供反馈。在每项任务中，健忘症患者逐渐学会将线索与适当的结果联系起来，正确率从50%提高到65%左右。可能是因为线索-结果的关联是概率性的，对特定试验结果的陈述性记忆对表现的作用并不像在试验中逐渐积累的信息那样大。然而，当训练时间超过50次时，陈述性记忆确实对表现有所贡献，因为随着进一步的训练，控制组的表现最终超过了健忘症患者。研究还表明，概率分类任务的表现并不是短期记忆中线索-结果关联知识的结果，因为当测试被5分钟的延迟中断时，对照组和健忘症患者都表现出显着的节省（实验2）。概率分类学习似乎为人类受试者提供了一种类似的习惯学习任务，这些习惯学习任务可以由海马损伤的动物正常获得。
Amnesic patients and control subjects participated in a study of probabilistic classification learning. In each of three tasks, four different cues were each probabilistically associated with one of two outcomes. On each trial, the cues could appear alone or in combination with other cues and subjects selected the outcome they thought was correct. Feedback was provided after each trial. In each task, the amnesic patients learned gradually to associate the cues with the appropriate outcome at the same rate as control subjects, improving from 50% correct to approximately 65% correct. Presumably because the cue-outcome associations were probabilistic, declarative memory for the outcomes of specific trials was not as useful for performance as the information gradually accrued across trials. Nevertheless, declarative memory does appear to make a contribution to performance when training is extended beyond approximately 50 trials, because with further training control subjects eventually outperformed the amnesic patients. It was also demonstrated that performance on the probabilistic classification task was not the result of holding knowledge of cue-outcome associations in short-term memory, because both control subjects and amnesic patients demonstrated significant savings when testing was interrupted by a 5-min delay (experiment 2). Probabilistic classification learning appears to provide an analog in human subjects for the habit learning tasks that can be acquired normally by animals with hippocampal lesions.