Motor-cognitive dual task performance: a multidimensional approach

随着年龄的增长，在双重任务条件下，姿势不稳定和跌倒的风险增加。工作记忆（WM）任务在这方面的要求特别高。姿势控制和WM操作之间的双任务干扰可能是由于注意力焦点必须以时间紧迫的方式在WM中的维护和处理操作与用于调整直立姿势的控制操作之间频繁且重复地切换。因此，在处理速度的差异，但也注意力的焦点（短期存储容量）的大小可能代表关键的限制，造成干扰下的双重任务conditions.Four关键问题出现，这是解决所提出的项目：（1）双任务成本取决于WM操作的需求，这种需求如何相互作用的需求姿势控制？(2)在这方面，处理速度或注意力焦点的大小是关键的限制因素吗？(3)潜在的大脑机制是什么？(4)什么是适当的培训策略，以提高双重任务的表现？为了揭示负责双任务干扰的神经认知机制，我们改变了对WM操作的需求和对姿势控制的需求，并比较了健康的年轻人和老年人受试者之间这些变化的交互作用。我们将这些影响定量估计，基于视觉注意力（TVA）的理论，个人的处理速度和短期存储容量。本研究应用功能磁共振成像、脑磁图和脑电分析技术，对静息状态和任务相关脑网络进行了研究，以揭示加工能力和双任务干扰的脑动力学机制。我们特别感兴趣的是一个功能性脑网络对另一个功能性脑网络的影响，以及这种影响如何随着双重任务成本的变化而变化。对轻度认知障碍（MCI）患者和恐怖性眩晕患者的评估将允许比较两种类型的中枢处理限制的病理影响：结构性（MCI）与策略性（恐怖性眩晕）。两组之间的大脑连接模式的比较将提供信息的网络基础上的一个可能的结构瓶颈，限制处理能力，和一个潜在的可修改的战略bottlenective.We的建议汇集运动科学，认知心理学，脑成像和临床神经学在一个跨学科的方法。预期的结果将不仅提高我们的理解的神经认知框架下的运动认知双重任务的要求，人类的表现。它们还可以支持姿势不稳定和衰老的新预防性干预策略的开发和理解。

With increasing age, postural instability and risk to fall increase under dual task conditions. Working memory (WM) tasks are particularly demanding in this regard. Dual task interference between postural control and WM manipulation may result from the fact that the attentional focus has to be frequently and repeatedly switched, in a time-critical manner, between maintenance and processing operations in WM, and control operations for adjusting upright posture. Therefore, differences in processing speed but also the size of the attentional focus (short-term storage capacity) may represent critical limitations causing interference under dual task conditions.Four critical questions arise, which are addressed by the proposed project: (1) Do dual task costs depend on the demand on WM manipulation and how does this demand interact with the demand on postural control? (2) Is processing speed or the size of the attentional focus the crucially limiting factor in this regard? (3) What are the underlying brain mechanisms? (4) What are appropriate training strategies to enhance dual task performance?To reveal the neuro-cognitive mechanisms responsible for dual task interference, we vary the demand on WM manipulation and the demand on postural control, and compare the interactive effects of these variations between healthy young and elderly subjects. We relate these effects to quantitative estimates, based on a theory of visual attention (TVA), of the individual processing speed and short-term storage capacity. Applying fMRI, MEG, and EEG analyses, resting state and task related brain networks are investigated to reveal the cerebral dynamics underlying processing capacity and dual task interference. We are particularly interested in the influences that one functional brain network exerts over another and how this influence changes with the variation of the dual task costs. Assessment of patients with mild cognitive impairment (MCI) and of patients with phobic vertigo will allow to compare the pathological effects of two types of central processing limitations: structural (in the case of MCI) versus strategic (in the case of phobic vertigo). A comparison of the cerebral connectivity patterns between both groups will provide information about the network basis of a possible structural bottleneck, limiting processing capacity, and of a potentially modifiable strategic bottleneck.Our proposal brings together movement science, cognitive psychology, brain imaging and clinical neurology in an interdisciplinary approach. The expected results will not only improve our understanding of the neuro-cognitive framework of human performance under motor-cognitive dual task requirements. They can also support the development and understanding of new preventive intervention strategies in postural instability and aging.