Neuroscience and Cognitive Technology Laboratory, Center for Technologies in Robotics and Mechatronics Component, Innopolis University, 1 Universitetskaya str., Innopolis, Republic of Tatarstan, Russia, 420500.
Saratov State Medical University, 112 Bolshaya Kazachia str., Saratov, Russia, 410012.
Sci Rep. 2021 Feb 10;11(1):3454. doi: 10.1038/s41598-021-82688-1.
A repeated presentation of an item facilitates its subsequent detection or identification, a phenomenon of priming. Priming may involve different types of memory and attention and affects neural activity in various brain regions. Here we instructed participants to report on the orientation of repeatedly presented Necker cubes with high (HA) and low (LA) ambiguity. Manipulating the contrast of internal edges, we varied the ambiguity and orientation of the cube. We tested how both the repeated orientation (referred to as a stimulus factor) and the repeated ambiguity (referred to as a top-down factor) modulated neuronal and behavioral response. On the behavioral level, we observed higher speed and correctness of the response to the HA stimulus following the HA stimulus and a faster response to the right-oriented LA stimulus following the right-oriented stimulus. On the neuronal level, the prestimulus theta-band power grew for the repeated HA stimulus, indicating activation of the neural networks related to attention and uncertainty processing. The repeated HA stimulus enhanced hippocampal activation after stimulus onset. The right-oriented LA stimulus following the right-oriented stimulus enhanced activity in the precuneus and the left frontal gyri before the behavioral response. During the repeated HA stimulus processing, enhanced hippocampal activation may evidence retrieving information to disambiguate the stimulus and define its orientation. Increased activation of the precuneus and the left prefrontal cortex before responding to the right-oriented LA stimulus following the right-oriented stimulus may indicate a match between their orientations. Finally, we observed increased hippocampal activation after responding to the stimuli, reflecting the encoding stimulus features in memory. In line with the large body of works relating the hippocampal activity with episodic memory, we suppose that this type of memory may subserve the priming effect during the repeated presentation of ambiguous images.
项目的重复呈现促进了其随后的检测或识别，这是一种启动现象。启动可能涉及不同类型的记忆和注意力，并影响大脑各个区域的神经活动。在这里，我们指示参与者报告以高（HA）和低（LA）歧义重复呈现的 Necker 立方体的方向。通过操纵内部边缘的对比度，我们改变了立方体的歧义性和方向。我们测试了重复的方向（称为刺激因素）和重复的歧义性（称为自上而下的因素）如何调节神经元和行为反应。在行为水平上，我们观察到在 HA 刺激后，对 HA 刺激的反应速度更快，正确性更高，并且在右向 LA 刺激后，对右向刺激的反应更快。在神经元水平上，对于重复的 HA 刺激，预刺激θ波段功率增加，表明与注意力和不确定性处理相关的神经网络被激活。刺激后，重复的 HA 刺激增强了海马体的激活。在对右向刺激后的右向 LA 刺激的行为反应之前，增强了楔前叶和左额回的活动。在重复 HA 刺激处理过程中，海马体激活增强可能证明检索信息以消除刺激的歧义并定义其方向。在对右向刺激后的右向 LA 刺激做出反应之前，楔前叶和左前额叶皮层的激活增加可能表明它们的方向匹配。最后，我们观察到在响应刺激后海马体的激活增加，反映了在记忆中对刺激特征的编码。与将海马体活动与情景记忆相关的大量研究结果一致，我们假设这种类型的记忆可能在模糊图像的重复呈现期间支持启动效应。
