Intentional switching between patterns of bimanual coordination depends on the intrinsic dynamics of the patterns.
Intentional switching between patterns of bimanual coordination depends on the intrinsic dynamics of the patterns.
复制标题
双手协调模式之间的有意切换取决于模式的内在动态。
作者：
J. Scholz;J. Kelso
从先前的理论和经验工作中得出的两个预测，证明了双手协调模式的自发变化是由于模式稳定性的丧失（即，非平衡相变）而引起的：(a)故意从一种模式切换到另一种模式所需的时间取决于模式本身的差异稳定性；(b)意图，定义为一种预期的行为模式，可以改变动态特征，例如，行为模式的整体稳定性。受试者在进行手指协调的同相或反相模式时，以六种运动频率中的一种有节奏地移动食指。根据听觉信号的提示，受试者从正在进行的模式切换到另一种模式。两个手指之间的相对运动阶段被用来描述正在进行的协调模式。在模式之间切换所花费的时间，或切换时间，以及相对相位波动被用来评估由于受试者改变模式的意图而导致的修改模式动态。所有受试者从同相模式切换到反相模式的速度明显慢于相反方向的切换。每个方向上切换时间的均值和分布都与模型预测一致。运动频率对切换时间几乎没有影响，这一发现也与模型一致。在研究的最高运动频率下，以反相位模式运动时，相对相位波动明显更大。结果表明，尽管有意影响会改变协调模式的内在动态，但这些动态对最终行为的影响始终存在，并且在高运动频率时尤其强烈。
Two predictions arising from previous theoretical and empirical work which demonstrated that spontaneous changes of bimanual coordination patterns result from a loss of pattern stability (i.e., a nonequilibrium phase transition) were tested: (a) that the time it takes to intentionally switch from one pattern to another depends on the differential stability of the patterns themselves; and (b) that an intention, defined as an intended behavioral pattern, can change the dynamical characteristics, e.g., the overall stability of the behavioral patterns. Subjects moved both index fingers rhythmically at one of six movement frequencies while performing either an in-phase or antiphase pattern of finger coordination. On cue from an auditory signal, subjects switched from the ongoing pattern to the other pattern. The relative phase of movement between the two fingers was used to characterize the ongoing coordinative pattern. The time taken to switch between patterns, or switching time, and relative phase fluctuations were used to evaluate the modified pattern dynamics resulting from a subject's intention to change patterns. Switching from the in-phase to the antiphase pattern was significantly slower than switching in the opposite direction for all subjects. Both the mean and distribution of switching times in each direction were found to be in agreement with model predictions. movement frequency had little effect on switching time, a finding that is also consistent with the model. Relative phase fluctuations were significantly larger when moving in the antiphase pattern at the highest movement frequencies studied. The results show that, although intentional influences act to modify a coordinative pattern's intrinsic dynamics, the influence of these dynamics on the resulting behavior is always present and is particularly strong at high movement frequencies.