Vandenberghe Muriel, Schmidt Nicolas, Fery Patrick, Cleeremans Axel
Université Libre de Bruxelles, Cognitive Science Research Unit, CP191, Avenue F.D. Roosevelt, 50, 1050 Bruxelles, Belgium.
Neuropsychologia. 2006;44(10):1629-41. doi: 10.1016/j.neuropsychologia.2006.03.022. Epub 2006 May 30.
Can associative learning take place without awareness? We explore this issue in a sequence learning paradigm with amnesic and control participants, who were simply asked to react to one of four possible stimuli on each trial. Unknown to them, successive stimuli occurred in a sequence. We manipulated the extent to which stimuli followed the sequence in a deterministic manner (noiseless condition) or only probabilistically so (noisy condition). Through this paradigm, we aimed at addressing two central issues: first, we asked whether sequence learning takes place in either condition with amnesic patients. Second, we asked whether this learning takes place without awareness. To answer this second question, participants were asked to perform a subsequent sequence generation task under inclusion and exclusion conditions, as well as a recognition task. Reaction times results show that amnesic patients learned the sequence only in the deterministic condition. However, they failed to be able to reproduce the sequence in the generation task. In contrast, we found learning for both sequence structures in control participants, but only control participants exposed to a deterministic sequence were successful in performing the generation task, thus suggesting that the acquired knowledge can be used consciously in this condition. Neither amnesic nor control participants showed correct old/new judgments in the recognition task. The results strengthen the claim that implicit learning is at least partly spared in amnesia, and the role of contextual information available for learning is discussed.
联想学习能否在无意识的情况下发生？我们在一个序列学习范式中探讨了这个问题，研究对象包括失忆症患者和对照组参与者，他们只需在每次试验中对四种可能的刺激之一做出反应。他们不知道的是，连续的刺激是以序列的形式出现的。我们操纵了刺激以确定性方式（无噪声条件）或仅以概率方式（有噪声条件）遵循序列的程度。通过这个范式，我们旨在解决两个核心问题：第一，我们询问失忆症患者在这两种条件下是否都能进行序列学习。第二，我们询问这种学习是否在无意识的情况下发生。为了回答第二个问题，要求参与者在包含和排除条件下执行后续的序列生成任务，以及一个识别任务。反应时间结果表明，失忆症患者仅在确定性条件下学习了序列。然而，他们在生成任务中无法再现该序列。相比之下，我们发现对照组参与者对两种序列结构都有学习，但只有接触到确定性序列的对照组参与者成功完成了生成任务，这表明在这种情况下获得的知识可以被有意识地使用。失忆症患者和对照组参与者在识别任务中均未表现出正确的旧/新判断。这些结果强化了这样一种观点，即失忆症中至少部分保留了内隐学习，并讨论了可用于学习的情境信息的作用。
