Breveglieri Rossella, Brandolani Riccardo, Diomedi Stefano, Lappe Markus, Galletti Claudio, Fattori Patrizia
Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna 40126, Italy
Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna 40126, Italy.
J Neurosci. 2025 Jan 1;45(1):e0659242024. doi: 10.1523/JNEUROSCI.0659-24.2024.
The interplay between attention, alertness, and motor planning is crucial for our manual interactions. To investigate the neural bases of this interaction and challenge the views that attention cannot be disentangled from motor planning, we instructed human volunteers of both sexes to plan and execute reaching movements while attending to the target, while attending elsewhere, or without constraining attention. We recorded reaction times to reach initiation and pupil diameter and interfered with the functions of the medial posterior parietal cortex (mPPC) with online repetitive transcranial magnetic stimulation to test the causal role of this cortical region in the interplay between spatial attention and reaching. We found that mPPC plays a key role in the spatial association of reach planning and covert attention. Moreover, we have found that alertness, measured by pupil size, is a good predictor of the promptness of reach initiation only if we plan a reach to attended targets, and mPPC is causally involved in this coupling. Different from previous understanding, we suggest that mPPC is neither involved in reach planning per se, nor in sustained covert attention in the absence of a reach plan, but it is specifically involved in attention functional to reaching.
注意力、警觉性和运动规划之间的相互作用对于我们的手动交互至关重要。为了探究这种相互作用的神经基础，并挑战注意力无法与运动规划相分离的观点，我们指导男女志愿者在关注目标时、在关注其他地方时或不限制注意力的情况下规划并执行伸手动作。我们记录了伸手起始的反应时间和瞳孔直径，并通过在线重复经颅磁刺激干扰内侧后顶叶皮层（mPPC）的功能，以测试该皮质区域在空间注意力和伸手动作之间相互作用中的因果作用。我们发现，mPPC在伸手动作规划和隐蔽注意力的空间关联中起关键作用。此外，我们还发现，只有当我们规划向关注目标伸手时，通过瞳孔大小测量的警觉性才是伸手起始及时性的良好预测指标，并且mPPC因果性地参与了这种耦合。与先前的理解不同，我们认为mPPC既不参与伸手动作规划本身，也不参与在没有伸手动作规划时的持续隐蔽注意力，但它特别参与对伸手动作起作用的注意力。
