Investigation of the control and monitoring of task sequences

描述(申请人提供)：许多日常任务需要多个目标和子目标的序列。例如，制作三明治的目标可能包含烤面包和涂抹调味品的子目标，这些子目标本身由一系列的子目标组成(例如，拿到一把刀，打开罐子等)。我们灵活地引导这些动作的能力被称为认知控制，这是额叶皮质的主要功能。最近的研究表明，额叶皮质是沿着肩尾轴组织的，以控制不同抽象水平(目标至子目标)的认知任务，或按层次控制。多数 然而，这项工作的大部分使用了非顺序任务；因此，只假设类似的控制机制将支持对任务序列的分层控制。这就留下了至少三个对我们理解额叶和认知控制功能至关重要的问题：1)额叶皮质的肩尾组织是否支持对任务序列的分层控制；2)整个任务序列的控制和监控的动力学是什么；以及3)任务序列的控制是如何随着学习而变化的。这三个问题将通过使用功能磁共振成像(FMRI)来研究以下假设来解决我们的三个目标：1)任务序列的分层控制由额叶皮质的肩尾组织支持；2)对于熟悉的任务序列，监控将以持续的方式(贯穿始终)或以瞬时的方式(在开始/结束)发生；以及3)监控将从在新序列上持续发生的方式过渡到在熟悉的学习序列的序列边界上瞬时发生。对将获得的任务序列的监视和控制的洞察将是理解我们如何执行日常任务的基础。这一认识对那些额叶功能障碍或受损的患者的生活质量尤为关键。这类患者通常不能独立生活，因为他们在规划和监控通常需要的任务序列方面存在困难。 与公共卫生相关：额叶皮质受损或功能障碍的患者通常无法独立生活，因为他们无法正确监控日常生活中常见的任务序列。虽然人们对额叶皮质对非连续任务施加这种控制的机制了解很多，但对为任务序列提供辅助的大脑区域的动态和结构知之甚少。目前的项目旨在直接调查和扩大我们对支持任务序列控制的神经系统的知识，这将为前额患者通过更好的诊断和改进的治疗获得更高质量的生活提供基础。

DESCRIPTION (provided by applicant): Many everyday tasks require sequences of multiple goals and subgoals. For example, the goal of making a sandwich may contain the subgoals of toasting the bread and spreading a condiment, which themselves consist of sequences of subgoals (e.g. getting a knife, opening the jar, etc.). Our ability to guide these actions flexiblyis known as cognitive control, and this is a primary function of the frontal cortex. Recent research has suggested that the frontal cortex is organized along the rostrocaudal axis to control cognitive tasks at different levels of abstraction (goals to sub-subgoals), or hierarchically. Most of this work, however, used non-sequential tasks; therefore, it has been only assumed that similar control mechanisms will support hierarchical control over sequences of tasks. This leaves at least three unanswered questions fundamental to our understanding of frontal lobe and cognitive control function, generally: 1) does the rostrocaudal organization of frontal cortex support hierarchical control of task sequences; 2) what are the dynamics of the control and monitoring throughout task sequences; and 3) how does the control of task sequences change with learning. These three questions will be addressed across our three aims by using functional magnetic resonance imaging (fMRI) to investigate the following hypotheses: 1) the hierarchical control of task sequences is supported by the rostrocaudal organization of frontal cortex; 2) monitoring will occur either in a sustained manner (throughout) or in a transient manner (at the beginning/end) for familiar task sequences; and 3) monitoring will transition from occurring in a sustained fashion over novel sequences to occurring transiently at sequence boundaries in familiar sequences with learning. The insight into the monitoring and control of task sequences that will be gained will be fundamental to the understanding of how we perform everyday tasks. This understanding is particularly crucial to the quality of life of those patients who have fronta lobe dysfunction or damage. Such patients often cannot live independently because they have trouble planning and monitoring the task sequences that are commonly required. PUBLIC HEALTH RELEVANCE: Patients with frontal cortical damage or dysfunction often are unable to live independently due to their inability to properly monitor and control the sequences of tasks that are common in everyday life. Although much is known about the mechanism by which the frontal cortex exerts this control over non-sequential tasks, comparatively little is known about the dynamics and structure of the brain areas that subserve sequences of tasks. The current project aims to directly investigate and broaden our knowledge of the neural systems that support the control of task sequences, which would provide the basis for progress towards frontal patients having a higher quality of life with better diagnoses and improved therapies.