Perceptual, Cognitive, and Motor Rigidity in Parkinson's Disease

运动强直是帕金森病（PD）的标志性症状，并且越来越多的证据表明非运动领域（如认知和人格）的强直。提出的问题是，这种刚性是否延伸到视觉感知，这是已知的PD异常。对健康成年人的感知研究集中在感知可逆性上，这是一种切换模糊不清的图像的能力。感知可逆性取决于通常受PD影响的大脑区域，包括皮质纹状体-丘脑皮质回路。本研究旨在探讨PD的知觉僵化，与这种知觉现象相关的机制，以及其与运动，认知和人格僵化的关系。将向非痴呆PD患者和年龄匹配的正常对照受试者提供可逆（可逆）图形，并评估其从一种感知解释转换为另一种感知解释的自然能力。将评估他们的双眼竞争（一个图像对另一个图像的感知优势）的交替率。为了探索可能的机制，潜在的刚性，将进行几个实验，包括意志控制，视觉空间的注意，并进行自下而上的处理时，刺激功能退化的能力检查。将评估参与者的认知僵化（执行功能的神经心理学测试，包括持续性）、运动僵化（手臂和腿部运动之间以及骨盆和胸部旋转之间的相对相位的步态测量）和个性僵化（问卷）。据推测，相对于对照组，个人与PD将显示减少知觉可逆性，因为他们将有一个降低的能力，故意“放手”的占主导地位的记忆，由于受损的额-纹状体-顶叶网络，支持选择性注意和集转移的认知能力。第二，它是假设自下而上的信息将有一个较弱的影响PD患者的知觉优势比对照组。第三，假设在PD组中，知觉僵化与认知、运动和人格僵化之间存在显著相关性，因为这些运动和非运动PD症状都源于基底神经节功能障碍的直接和间接影响。了解帕金森病患者知觉僵化的本质，可以为知觉干预的发展提供信息，以提高帕金森病患者的生活质量和独立性。

Motor rigidity is a hallmark symptom of Parkinson's disease (PD), and there is increasing evidence for rigidity in non-motor domains such as cognition and personality. The question is raised as to whether such rigidity extends to visual perception, which is known to be abnormal in PD. Research on perception with healthy adults has focused on perceptual reversibility, which is the ability to switch the image of a bistable ambiguous figure. Perceptual reversibility depends on brain areas that are typically affected by PD, including corticostriatal-thalamocortical circuitry. The proposed study aims to examine perceptual rigidity in PD, the mechanisms associated with this perceptual phenomenon, and its association with motor, cognitive and personality rigidity. Non-demented PD patients and age-matched normal control participants will be presented with bistable (reversible) figures and will be assessed for their natural ability to switch from one perceptual interpretation to the other. Their alternation rate for binocular rivalry (perceptual dominance of one image over the other one) will be assessed. In order to explore possible mechanisms underlying rigidity, several experiments will be conducted including examinations of volitional control, visuospatial attention, and the ability to engage in bottom-up processing when stimulus features are degraded. The participants will be assessed for cognitive rigidity (neuropsychological tests of executive function including perseveration), motor rigidity (gait measures of relative phase between arm and leg movements and between pelvic and thoracic rotation), and personality rigidity (questionnaire). It is hypothesized that relative to the control group, individuals with PD will show reductions in perceptual reversibility in that they will have a reduced ability to intentionally "let go" of the dominant percept due to compromised fronto-striatal-parietal networks that support the cognitive abilities of selective attention and set-shifting. Second, it is hypothesized that bottom-up information will have a weaker effect on perceptual dominance in PD patients than in control participants. Third, it is hypothesized that in the PD group, there will be significant correlations between perceptual rigidity and cognitive, motor, and personality rigidity as these motor and non-motor PD symptoms all emanate from the direct and indirect influence of the dysfunctional basal ganglia. Understanding the nature of perceptual rigidity in PD can inform the development of perceptual interventions to enhance PD patients' quality of life and independence.