Young William R, Rodger Matthew W M, Craig Cathy M
Centre for Sports Medicine and Human Performance, Brunel University, Uxbridge, UB8 3PH, UK.
School of Psychology, Queen׳s University Belfast, Belfast, BT9 5BN, UK.
Neuropsychologia. 2014 May;57:140-53. doi: 10.1016/j.neuropsychologia.2014.03.009. Epub 2014 Mar 25.
A common behavioural symptom of Parkinson׳s disease (PD) is reduced step length (SL). Whilst sensory cueing strategies can be effective in increasing SL and reducing gait variability, current cueing strategies conveying spatial or temporal information are generally confined to the use of either visual or auditory cue modalities, respectively. We describe a novel cueing strategy using ecologically-valid 'action-related' sounds (footsteps on gravel) that convey both spatial and temporal parameters of a specific action within a single cue.
The current study used a real-time imitation task to examine whether PD affects the ability to re-enact changes in spatial characteristics of stepping actions, based solely on auditory information. In a second experimental session, these procedures were repeated using synthesized sounds derived from recordings of the kinetic interactions between the foot and walking surface. A third experimental session examined whether adaptations observed when participants walked to action-sounds were preserved when participants imagined either real recorded or synthesized sounds.
Whilst healthy control participants were able to re-enact significant changes in SL in all cue conditions, these adaptations, in conjunction with reduced variability of SL were only observed in the PD group when walking to, or imagining the recorded sounds.
The findings show that while recordings of stepping sounds convey action information to allow PD patients to re-enact and imagine spatial characteristics of gait, synthesis of sounds purely from gait kinetics is insufficient to evoke similar changes in behaviour, perhaps indicating that PD patients have a higher threshold to cue sensorimotor resonant responses.
帕金森病（PD）常见的行为症状是步长（SL）缩短。虽然感觉提示策略可有效增加步长并减少步态变异性，但目前传达空间或时间信息的提示策略通常分别局限于视觉或听觉提示方式的使用。我们描述了一种新颖的提示策略，使用具有生态效度的“与动作相关”声音（在砾石上行走的脚步声），该声音在单个提示中传达特定动作的空间和时间参数。
本研究使用实时模仿任务来检查PD是否仅基于听觉信息就会影响重新 enact 步行动作空间特征变化的能力。在第二个实验环节中，使用从足部与行走表面的动力学相互作用记录中衍生的合成声音重复这些程序。第三个实验环节检查当参与者想象真实录制或合成声音时，参与者走向动作声音时观察到的适应性是否得以保留。
虽然健康对照参与者能够在所有提示条件下重新 enact 步长的显著变化，但只有在PD组中，当走向或想象录制声音时，才观察到这些适应性变化以及步长变异性的降低。
研究结果表明，虽然步行动作的录音传达动作信息以使PD患者能够重新 enact 并想象步态的空间特征，但仅从步态动力学合成声音不足以引发类似的行为变化，这可能表明PD患者对提示感觉运动共振反应的阈值更高。
