Valdez André B, Amazeen Eric L
Arizona State University, AZ, USA.
Nonlinear Dynamics Psychol Life Sci. 2009 Oct;13(4):369-92.
The present study tested for 1/f noise to examine how timing and target constraints affect cognitive processes in aiming. Participants pointed to targets of varied height and width at preferred speed (Experiment 1) and as quickly as possible (Experiment 2). Results show greater intensity of 1/f noise, or long-range correlation in variability, at preferred speed and with increased accuracy demands perpendicular to the target (i.e., related to height). Prior research suggests that increased 1/f noise in movement reflects increased coordination of processes at different timescales (e.g., planning and control), particularly when there is more time to complete the movement. Previous studies also suggest that target height constraints promote more reliance on both predictive and reactive control, as more time is spent during initial aiming and adjustment. Thus, present results expand on what we know about aiming movements in two ways: (a) by further suggesting a non-orthogonal relation between planning (coarse aiming) and control (fine tuning) that is time dependent; and (b) by demonstrating that such an integration of processes, reflected in distinct patterns of 1/f noise, may be modulated by multiple environmental characteristics (i.e., target shape).
本研究检测了1/f噪声，以考察时间和目标限制如何影响瞄准过程中的认知过程。参与者以偏好速度（实验1）和尽可能快的速度（实验2）指向不同高度和宽度的目标。结果显示，在偏好速度下以及垂直于目标方向（即与高度相关）的准确性要求提高时，1/f噪声的强度更大，或者说变异性中存在更强的长程相关性。先前的研究表明，运动中1/f噪声的增加反映了不同时间尺度上（如计划和控制）过程协调性的提高，特别是在有更多时间完成运动时。先前的研究还表明，目标高度限制会促使更多地依赖预测性和反应性控制，因为在初始瞄准和调整过程中会花费更多时间。因此，目前的结果从两个方面扩展了我们对瞄准动作的认识：（a）进一步表明计划（粗略瞄准）和控制（微调）之间存在时间依赖的非正交关系；（b）证明这种反映在1/f噪声不同模式中的过程整合可能会受到多种环境特征（即目标形状）的调节。
