Olfaction: From Coding to Memory Team, Lyon Neuroscience Research Center, CNRS UMR 5292, INSERM U1028, Université Lyon 1, 50 Avenue Tony Garnier, F-69366 Lyon cedex 07, France.
J Neurosci Methods. 2013 Feb 15;213(1):22-31. doi: 10.1016/j.jneumeth.2012.11.010. Epub 2012 Nov 29.
Episodic memory is defined as the conscious recollection of a personal event (What) in its spatial (Where) and contextual (Which context) environment. In existing approaches, human episodic memory is either explored separately from real-life situations or is not fully controlled. In this study, we propose an intermediate approach, inspired by animal studies, that permits the control of the encoding and recall phases, while still being ecologically valid. As odors are known to be especially evocative reminders, we explored the memory of olfactory episodes. During trial-unique encoding, participants freely explored three episodes, one episode per day, each composed of three unnamable odors (What) that were positioned at specific locations on a board (Where) within a visual context (Which context). On the fourth day, both old and new odors were presented, and when an odor was recognized, the participants had to remember both its spatial location and the visual context in which it occurred. In Experiment 1, the participants were highly proficient at recognizing odors, and they recall the spatio-contextual environment associated with these odors in approximately half of the trials. To adapt the recall procedure to the constraints of fMRI, we conducted Experiment 2 demonstrating that trial repetition did not disturb the memory process. Thus, we first validated our protocol, which investigates the memory of olfactory episodes in a fully controlled way that is as close as possible to real-life situations. Then, we demonstrated the adaptability of our protocol for the future exploration of the neural networks implicated in episodic recall.
情景记忆被定义为对个人事件（What）在其空间（Where）和上下文（Which context）环境中的有意识回忆。在现有的方法中，人类情景记忆要么与现实生活情况分开探索，要么无法完全控制。在这项研究中，我们受动物研究的启发，提出了一种中间方法，该方法允许控制编码和回忆阶段，同时仍然具有生态有效性。由于众所周知气味是特别有启发性的提示，我们探索了嗅觉情景记忆。在独特的试验编码期间，参与者自由探索三个情景，每天一个情景，每个情景由三个无法命名的气味（What）组成，这些气味位于板上的特定位置（Where），并在视觉环境（Which context）中。第四天，同时呈现旧和新气味，当识别出一种气味时，参与者必须记住其空间位置和出现它的视觉环境。在实验 1 中，参与者非常熟练地识别气味，并且他们在大约一半的试验中回忆出与这些气味相关的空间-上下文环境。为了使回忆过程适应 fMRI 的限制，我们进行了实验 2，证明试验重复不会干扰记忆过程。因此，我们首先验证了我们的方案，该方案以尽可能接近现实生活的方式，对嗅觉情景记忆进行完全控制的研究。然后，我们展示了我们的方案对未来探索涉及情景回忆的神经网络的适应性。
