各位老师：

您好！由实验室舒华老师邀请了University of  California, Irvine的Steven L.  Small教授来实验室做讲座，欢迎感兴趣的老师和同学参加。学术演讲信息如下：

讲座时间：6月15日（周五）上午10:10

讲座地点：小红楼三层大会议室

主讲人：Pro. Steven L.  Small,  University of California, Irvine）

讲座题目：What is the Role of  the Parietal-Premotor Pathway in Language Comprehension? Is this Relevant for  Language Recovery after Stroke?”

内容摘要：An important source of information for language  comprehension comes from the perception of action, including the movements of  the mouth and hands. The neural interactions involved in processing this  information involve the premotor cortex, the inferior parietal lobule, and the  superior temporal gyrus. These regions and the neural connections among them  comprise a human system for observation-execution matching that appears to have  a phylogenetic basis in the mirror neuron system of the macaque. There is some  controversy about the extent to which this system operates by covert simulation  of perceived action. In this talk, we present data from several studies of  audiovisual language comprehension that address the issues.First we discuss the role of action understanding in speech  perception, and show how it aids phonological disambiguation across  environmental and contextual variation, and that the motor cortex plays a  fundamental role in the process. Next, we discuss the role of action  understanding in higher order language comprehension. Finally, we present data  directly addressing the putative role of motor simulation in comprehension. We  conclude that the process of understanding language involves multimodal sensory  and motor processing, but perhaps not simulation per se, and that the overall  process forms a distributed circuit encoding comprehension. Some final comments  will address the usefulness of this basic work for translational efforts in  stroke recovery.

主讲人介绍：

Pro. Steven L. Small  Ph.D.,  M.D.Professor and Chair,  NeurologyDepartment of  NeurologyDepartment of  Neurobiology and BehaviorDepartment of Cognitive  Sciences

Research  Interests：Neurobiology of  Language, Neural Repair, Computational Neuroscience

Research  Abstract：Our laboratory uses  functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI),  high density electroencephalography (hd-EEG), and transcranial magnetic  stimulation (TMS) to study the organization of the normal human cerebral cortex  and the changes that it undergoes after neurological injury, particularly  stroke. We focus particularly  on speech, language, and hand motor function. In the study of normal adults, we  have found that the language areas of the brain are more widely distributed than  previously thought, extending to brain regions that are anatomically removed  from those originally postulated by Broca, Wernicke, and Déjérine, and extending  to both cerebral hemispheres. To characterize this distributed functional  anatomy, we use multivariate mathematical modeling approaches across brain  regions and methods of analyzing distributed population codes within regions. We  have recently found that the comprehension of speech requires neural processing  in areas thought to be primarily involved in production, and that the underlying  mechanism is likely to include action simulation via the mirror neuron system.  We have also determined that the circuits for higher-order language  comprehension are highly integrated with those for encoding information into  memory, and that activity in these circuits depends critically on the  information value of what is heard. In the motor system, we  have found significant overlap in the neural circuits for kinetic motor imagery  and overt execution of finger movements, but that when examining the circuit  using multivariate distributed modeling, the interactions among cerebellar,  parietal, and premotor (frontal) cortices on can be seen to differ  significantly. In the study of expert motor performance, we recently  demonstrated that professional athletes have a much more constrained and focused  pattern of brain activation than novices, incorporating mainly primary and  secondary motor cortices, without any significant limbic activation as found in  novices.In our studies of  stroke recovery of speech, language, and hand motor function, we perform  longitudinal behavioral testing and brain imaging during natural recovery and  during treatment interventions. During natural recovery, we have shown that  patients' performance improves and their pattern of brain activity changes, and  that the hemisphere ipsilateral to the injury and the cerebellum contralateral  to the injury play the major role in recovery. Various intervention studies are  in progress, both for aphasia and hand motor recovery, and these studies aim to  take advantage of the process of observation-execution matching, the human  analogue to the macaque mirror neuron system, to improve function after stroke  and the understand the brain mechanisms of recovery.

    此致

敬礼

认知神经科学与学习国家重点实验室

2012年6月13日