I Think, Therefore Eyeblink
作者研究了经典条件反射是否需要被试有意识地察觉刺激之间的关联。实验让被试完成两项反应时任务，确保他们注意实验刺激，然后将两项任务交错，使一项任务中的视觉刺激与另一项任务中的气吹刺激形成巴甫洛夫条件反射。许多被试没有意识到这种关联，尽管视觉刺激与气吹刺激多次在时间上接近且相关，他们仍未能表现出差异性的眨眼条件反射。通过口头指导操纵意识水平后，被试的意识显著提高，差异性眨眼反应也随之增强。这些结果对双系统理论（认为存在独立于认知的自动联想系统）提出质疑，并有力证明与意识相关的认知过程在学习中发挥因果作用。
Can conditioning occur without conscious awareness of the contingency between the stimuli? We trained participants on two separate reaction time tasks that ensured attention to the experimental stimuli. The tasks were then interleaved to create a differential Pavlovian contingency between visual stimuli from one task and an airpuff stimulus from the other. Many participants were unaware of the contingency and failed to show differential eyeblink conditioning, despite attending to a salient stimulus that was contingently and contiguously related to the airpuff stimulus over many trials. Manipulation of awareness by verbal instruction dramatically increased awareness and differential eyeblink responding. These findings cast doubt on dual-system theories, which propose an automatic associative system independent of cognition, and provide strong evidence that cognitive processes associated with awareness play a causal role in learning.