Denyer Ronan, Boyd Lara A
University of British Columbia, Vancouver.
J Cogn Neurosci. 2025 Mar 1;37(3):582-601. doi: 10.1162/jocn_a_02268.
Spatially congruent cues increase the speed of bimanual reach decisions compared with abstract symbolic cues, particularly for asymmetric reaches. Asymmetric rhythmic bimanual movements are less stable than symmetric rhythmic movements, but it is not well understood if spatially congruent cues similarly increase the stability of asymmetric rhythmic bimanual movements. To address this question, in Experiment 1, participants performed symmetric and asymmetric bimanual rhythmic finger tapping movements at different movement frequencies in time with flickering spatially congruent and abstract symbolic stimuli. As expected, symmetric movements were more stable. Spatially congruent cues similarly increased the stability of symmetric and asymmetric movements compared with abstract symbolic cues. The benefits of spatial congruence and movement symmetry were restricted to high movement frequencies (>2 Hz). To better understand if the emergence of these effects at high movement frequencies was driven by a change in movement strategy, in Experiment 2, video of the hands was concurrently recorded during task performance. Markerless motion tracking software revealed that participants switched from discontinuous to continuous movement strategies with increasing movement frequency. Because discontinuous and continuous movements are thought to be controlled by distinct neurocognitive systems, this might explain why the beneficial effects of spatial congruence and response symmetry emerged only at high movement frequencies. Overall, results from the current study indicate that the perceptual quality of the stimulus use to cue movement frequency can have powerful effects on the stability of rhythmic bimanual movements, but that these effects may depend on whether discontinuous or continuous movement strategies are selected.
与抽象符号线索相比，空间一致线索能提高双手够物决策的速度，尤其是对于非对称够物。非对称有节奏的双手运动比对称有节奏的运动稳定性更低，但空间一致线索是否同样能提高非对称有节奏双手运动的稳定性，目前还不太清楚。为了解决这个问题，在实验1中，参与者随着闪烁的空间一致和抽象符号刺激，以不同的运动频率进行对称和非对称的双手有节奏手指敲击运动。正如预期的那样，对称运动更稳定。与抽象符号线索相比，空间一致线索同样提高了对称和非对称运动的稳定性。空间一致性和运动对称性的益处仅限于高运动频率（>2Hz）。为了更好地理解这些效应在高运动频率下的出现是否是由运动策略的变化驱动的，在实验2中，在任务执行过程中同时记录双手的视频。无标记运动跟踪软件显示，随着运动频率的增加，参与者从间断运动策略转变为连续运动策略。由于间断运动和连续运动被认为是由不同的神经认知系统控制的，这可能解释了为什么空间一致性和反应对称性的有益效应仅在高运动频率下出现。总体而言，当前研究结果表明，用于提示运动频率的刺激的感知质量对有节奏的双手运动的稳定性可能有强大影响，但这些影响可能取决于是否选择了间断或连续运动策略。
