Funding for Cognitive Imaging

磁共振成像（MRI）是一种强大的研究工具，可以在对受试者没有风险的情况下研究人脑的解剖结构和功能。我们正在使用这种技术来研究三种常见的疾病：左大脑半球中风;轻度到中度阿尔茨海默病;和一种慢性癫痫，称为颞叶癫痫。中风我们正在研究左大脑半球中风后交流障碍（失语症）的患者。每年约有25，000名患者在中风后留下持续性失语症。这种情况的治疗远非完美，在许多情况下，大部分未经证实的好处。它主要采取在言语和语言治疗师的监督下进行行为再训练的形式。一个特别困难的问题是预测自然恢复的程度。这通常是最大的三个月，但恢复的数量可以是非常可变的。中风的大小确实影响结果。然而，其他因素似乎也参与其中，而这些因素是什么还不清楚。许多人认为恢复是因为语言从左脑“切换”到右脑，但这种情况发生的证据很少。有更好的证据表明，恢复是由于左半球未受损部分的广泛重组，我们的预测是，如果关键通路保持完整，那么恢复会更好。因此，我们招募了50名失语性中风患者，在第一阶段，我们评估他们在中风第一周内的语言能力。我们对语言产生特别感兴趣，因为患者发现表达自己的能力受损是他们病情中最令人沮丧的方面。然后我们在三个月时重新评估它们，这样我们就有了一个衡量它们恢复的“轨迹”：好的、坏的或无关紧要的。我们还做了详细的MRI，早期和晚期，以评估中风的边界，当患者试图说话时整个大脑的功能，以及整个大脑的通路（白色物质束）的完整性。我们预测，这将使相当深入的因素，为良好的自然恢复，这方面的知识将是必不可少的，在通知改善未来的治疗策略。阿尔茨海默氏病阿尔茨海默氏病（AD）的主要特点是健忘，特别是对口头信息。记住一个人刚刚被告知的内容有三个阶段：记录信息（即注意说话者以理解所说的内容）;将信息编码为更持久的记忆;然后在需要时检索记忆。这些不同的阶段依赖于大脑中非常不同的网络。大多数研究集中在编码和检索阶段。我们正在研究第一阶段，特别是注意力的作用。在AD的早期阶段，语言功能是完整的，所以言语不理解不是问题。相反，我们认为，病人不注意。注意力取决于右脑系统。我们正在研究这个系统在通信过程中，使用功能和解剖MRI序列。我们也在观察用于缓解AD某些症状的药物是否对右半球系统有特别强的作用。癫痫有些癫痫患者通过手术来预防发作。一种常见的手术是切除大脑一个脑叶的前部，即颞叶。令人惊讶的是，这对患者的高级心理功能的影响相对较小。我们正在调查的假设，频繁的癫痫发作活动，在整个生命的病人已经导致重组的颞叶网络，从而保护病人从一个重大的缺陷后，手术已经完成。这将告诉我们更多关于大脑的保护性“可塑性”。

Magnetic resonance imaging (MRI) is a powerful research tool, allowing both the anatomy and function of the human brain to be studied without risk to the subject. We are using this technique to study three common diseases: left cerebral hemisphere stroke; mild-to-moderate Alzheimer's disease; and a form of chronic epilepsy, know as temporal lobe epilepsy.StrokeWe are investigating patients who have impaired communication (aphasia) after a left cerebral hemisphere stroke. About 25,000 patients each year are left with persistent aphasia after stroke. Treatment for this condition is far from perfect, and in many instances largely of unproven benefit. It mostly takes the form of behavioural retraining, under the supervision of speech and language therapists. A particular difficulty is the problem of predicting the degree of natural recovery that will occur. This is usually maximal by three months, but the amount of recovery can be very variable. The size of the stroke does influence outcome. However, other factors seem to be involved, and what these are are not knowm. Many people believe that recovery is because language 'switches' from the left to the right cerebral hemisphere, but the evidence that this happens is slender. There is much better evidence that recovery is due to wide reorganisation of undamaged parts of the left hemisphere, and our prediction is that if critical pathways remain intact then recovery is much better. Therefore, we are recruiting 50 patients after aphasic stroke, and in the first phase we are assessing their language abilities within the first week of stroke. We are particularly interested in speech production, as patients find an impaired ability to express themselves the most frustrating aspect of their condition. We then reassess them at three months, and so we have a measure of their 'trajectory' of recovery: good, bad or indifferent. We also do detailed MRI, early and late, to assess the boundaries of the stroke, the function of the whole brain as the patients try to speak, and the integrity of pathways (white matter tracts) throughout the brain. We predict that this will give considerable insight into the factors necessary for good natural recovery, and this knowledge will be essential in informing improved future therapeutic strategies.Alzheimer's diseaseThe cardinal feature of Alzheimer's disease (AD) is forgetfulness, particularly for verbal information. There are three stages for remembering what one has just been told: registering the information (that is paying attention to the speaker to understand what is being said); encoding the information as a longer lasting memory; and then retrieving that memory when required. These different stages rely on very different networks in the the brain. Most research has concentrated on the encoding and retrieval stages. We are researching the first stage, and specifically the role of attention. In the early stages of AD, language functions are intact, so undertanding speech is not the problem. Rather, we argue, the patients are inattentive. Attention depends on a right cerebral hemisphere system. We are investigating this system during communication, using functional and anatomical MRI sequences. We are also observing whether the drugs used to alleviate some of the symptoms of AD have a particularly strong action on this right hemisphere system.EpislepsySome patients with epilepsy have surgery to prevent their attacks. One common operation is to remove the front pary of one lobe of the brain, the temporal lobe. Surprisingly, this has a relatively minor effect on the patient's higher mental functions. We are invetigating the hypothesis that frequent seizure activity throughot the lifetime of the patient has resulted in reorganisation of the temporal lobe networks, thus protecting the patient from a major deficity after the surgery has been completed. This will inform us more about the protective 'plasticity' of the brain.