Individual recovery of cognitive defects after stroke

中风是发达国家导致严重残疾的主要原因，许多人长期患有语言、知觉、运动控制和记忆方面的缺陷。急性中风患者及其家人首先要问的一些问题是：完全康复的可能性有多大？对我来说，什么是现实的康复？到目前为止，还没有个人对这个紧迫的问题做出回应。目前，我们对长期复苏的建议只是基于非常笼统的观察。大约三分之二的急性中风引起的认知缺陷将会恢复；三分之一的患者将经历慢性损害。我们认为，脑成像可以与急性行为相结合，为个体的长期预后提供重要的生物标志物。预后的改善不仅可以提供现实的期望，而且还将指导个性化的治疗(例如，康复与补偿)。作为一般原理的展示，我们将集中于中风对右半球的影响，即空间定向和注意力障碍。这些缺陷是各种日常任务恢复不佳的有力预测因素，包括运动恢复不佳、一般认知功能障碍和康复阻力。基于我们之前的工作，我们现在对常见右脑疾病的解剖学基础有了明确的预测。具体地说，在主动知觉忽视任务中，损伤导致坐姿和凝视的消极偏向，以及以身体为中心的偏向(我们称之为自我中心忽视)。另一方面，更多的后部损伤似乎会导致个体物体内的空间偏向(同位中心性忽视)。相反，顶叶交界处的损伤会导致灭绝(当面对多个同时发作的物体时，这是一种偏见)。我们的目标是进行第一次前瞻性的纵向研究，以了解个人的长期康复情况。我们断言，急性结构和功能脑成像的结合，以及一套精心设计的急性和结果行为测量，将使我们能够了解潜在的生理学，并帮助我们确定需要哪些测量来准确预测。

Stroke is the leading cause of major disability throughout the developed world with many individuals suffering from long term deficits in speech, perception, motor control and memory. Some of the first questions of acute stroke patients and their families are: 'What is the likelihood for a full recovery? What is a realistic recovery in my case?' So far, there is no individual response to this urgent question. Currently our advice regarding long-term recovery is only informed by very general observations. About two-thirds of the cognitive deficits evoked by an acute stroke will recover; one-third of the patients will experience chronic impairments. We propose that brain imaging can be combined with acute behaviour to provide an important biomarker for individual long-term prognosis. Improved prognosis could not only provide realistic expectations, but would also guide individually tailored treatment (e.g. rehabilitation versus compensation). As a showcase for the general principle we will concentrate on the consequences of stroke to the right hemisphere, namely the disorders of spatial orientation and attention. These deficits are strong predictors for poor recovery on a wide range of everyday tasks including poor motor recovery, general cognitive dysfunction and resistance to rehabilitation. Based on our previous work, we now have clear predictions regarding the anatomical underpinnings of common right hemisphere disorders. Specifically, injury to perisylvian regions leads to passive biases in posture and gaze, as well as body-centered biases during active perceptual neglect tasks (which we refer to as egocentric neglect). On the other hand, more posterior injury appears to lead to spatial biases within individual objects (allocentric neglect). In contrast, injury to the temporoparietal junction results in extinction (a bias when confronted by multiple objects that share a simultaneous onset). Our objective is to conduct the first prospective longitudinal study informed by these recent findings in order to understand individual long-term recovery. We assert that the combination of acute structural and functional brain imaging, as well as a carefully designed set of acute and outcome behavioral measures, will allow us to understand the underlying physiology and help us determine which measures are required for accurate prognosis.