Tretyakova Vera, Pavlova Anna, Arapov Vasily, Rytikova Anna, Vorobiova Alicia, Prokofyev Andrey, Chernyshev Boris, Stroganova Tatiana
Center for Neurocognitive Research (MEG Center), Moscow State University of Psychology and Education, Moscow, Russia.
School of Psychology, HSE University, Moscow, Russia.
PLoS One. 2025 Jul 2;20(7):e0325977. doi: 10.1371/journal.pone.0325977. eCollection 2025.
Action word learning is believed to rely on mechanisms of Hebbian learning. However, this biological mechanism requires activation of the neural assemblies representing a word form and a corresponding movement to repeatedly overlap in time. In reality, though, these associated events could be separated by seconds. In the current MEG study, we examined trial-and-error learning of associations between novel auditory pseudowords and movements of specific body parts. We aimed to explore how the brain bridges the temporal gap between the transient activity evoked by auditory input and the preparatory motor activation before the corresponding movement. To address this, we compared learning-induced changes in neuromagnetic responses locked to the onset of the stimulus and to the onset of the movement. As learning progressed, both types of neural responses showed sustained enhancement during the delay period between the auditory pseudoword and the required movement. Cortical sources of this learning-induced increase were localized bilaterally in the lateral and medial temporal cortices. Notably, the learning effect was significantly stronger when measured time-locked to the movement onset, rather than to the pseudoword onset. This suggests that once pseudoword-movement associations were reliably acquired, extensive regions of the auditory cortex were reactivated in synchrony with the preparation for the upcoming movement. Such reactivation likely served to bring together in time the representations of the correct action and the preceding auditory cue. This temporal alignment could enable Hebbian learning, leading to long-lasting synaptic changes in temporally correlated neural assemblies.
动作词学习被认为依赖于赫布学习机制。然而,这种生物学机制要求代表单词形式和相应动作的神经集合的激活在时间上反复重叠。但在现实中,这些相关事件可能相隔数秒。在当前的脑磁图(MEG)研究中,我们考察了新的听觉假词与特定身体部位动作之间关联的试错学习。我们旨在探究大脑如何弥合听觉输入引发的瞬态活动与相应动作之前的准备性运动激活之间的时间间隙。为了解决这个问题,我们比较了与刺激 onset 和动作 onset 锁定的神经磁反应的学习诱导变化。随着学习的进行,在听觉假词和所需动作之间的延迟期内,这两种类型的神经反应均显示出持续增强。这种学习诱导增加的皮层源在双侧颞叶外侧和内侧皮层定位。值得注意的是,当与动作 onset 锁定测量时,学习效应明显强于与假词 onset 锁定测量时。这表明一旦可靠地获得了假词 - 动作关联,听觉皮层的广泛区域会与即将到来的动作准备同步重新激活。这种重新激活可能有助于在时间上把正确动作的表征和先前的听觉线索聚集在一起。这种时间对齐可以实现赫布学习,导致时间相关神经集合中持久的突触变化。