A MEG Study of Saccardic Eye Movement Effects on Word Processing

眼跳眼动对文字处理影响的脑磁图研究

• 批准号: 7145501
• 负责人: SIMONA TEMEREANCA IBANESCU
• 金额: $ 8.75万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7145501
• 关键词: attention; behavior test; bioimaging /biomedical imaging; biophysics; brain imaging /visualization /scanning; clinical research; cognition; electroencephalography; fovea centralis retinae; human subject; interview; language; magnetic resonance imaging; magnetoencephalography; neural information processing; psychophysics; reading; saccades; time resolved data; visual perception; visual stimulus; vocabulary

DESCRIPTION (provided by applicant): Saccades are rapid eye movements employed during active vision to bring the target of interest onto the fovea, the retinal area of highest visual acuity. They are critical to essential human behaviors such as reading and visual exploration of the environment, with recent perceptual studies emphasizing their active role in regulating the flow of visual information. The impact of saccades on word recognition remains little understood, however, because most studies have focused on static visual processing wherein visual stimuli are presented during constant fixation. The aim of this research proposal is to investigate the spatial temporal dynamics of brain activity as words are processed following saccades, using a multimodal imaging approach that combines whole-head magnetoencephalography (MEG), electroencephalography (EEG), anatomical magnetic resonance imaging (MRI), and psychophysical methods. Integrating MEG/EEG with MRI provides a powerful tool for human brain imaging by allowing source localization of the magnetic and electrical signal on a millimeter spatial scale, with the high temporal resolution (milliseconds) inherent to MEG/EEG recordings. Our working hypothesis is that word processing is facilitated within a narrow time window following an eye movement and we aim to uncover the neuronal mechanisms involved. To distinguish between different postsaccadic effects (visual, motor, and attentional influences), we will compare the brain activations to words presented following saccades vs. externally generated image motion that mimics that during an eye movement. Word frequency and repetition priming effects within a lexical decision task will be used to investigate postsaccadic effects on different aspects (visual feature, orthographic, phonological, semantic) of language processing. To our knowledge, this is the first study to investigate saccadic modulation of word processing using multimodal MEG/EEG/MRI recordings. This work will contribute to elucidating the neural processes underlying control of eye movements and attention, and will advance our understanding of how active vision influences brain activity and visual processing during reading. Furthermore, results are expected to have important implications for clinical research in dyslexia, attention-deficit hyperactivity disorder (ADHD) and schizophrenia, where eye-movements have been shown to be abnormal.

描述（由申请人提供）：扫视是在主动视觉期间采用的快速眼动动作，以将感兴趣的目标带入Fovea，这是视力最高的视网膜区域。它们对人类基本行为（例如对环境的阅读和视觉探索）至关重要，最近的感知研究强调了它们在调节视觉信息流动中的积极作用。但是，扫视对单词识别的影响尚不清楚，因为大多数研究都集中在静态视觉处理上，其中在恒定固定过程中会呈现视觉刺激。这项研究建议的目的是使用多模式成像方法在扫视后处理脑活动的空间时间动力学，该方法结合了全头磁性磁摄影术（MEG），脑电图（EEG），解剖学磁共振成像（MRI）和心理学物理学方法。将MEG/EEG与MRI集成，为人脑成像提供了强大的工具，它通过允许在毫米空间尺度上定位磁性和电信号，具有高时间分辨率（毫秒）固有的MEG/EEG记录。我们的工作假设是，在眼睛运动后，在狭窄的时间窗口内促进了文字处理，我们旨在揭示所涉及的神经元机制。为了区分不同的后acadic效应（视觉，运动和注意力影响），我们将将大脑的激活与扫视与外部产生的图像运动呈现的单词进行比较。词汇决策任务中的单词频率和重复启动效应将用于研究对语言处理的不同方面（视觉特征，拼字，语音，语义，语义）的后听效应。据我们所知，这是第一项研究使用多模式MEG/EEG/MRI记录来研究单词处理的saccadic调制的研究。这项工作将有助于阐明眼睛运动和注意力控制的神经过程，并将促进我们对主动视力在阅读过程中如何影响大脑活动和视觉处理的理解。此外，预计结果对阅读障碍，注意力缺陷多动障碍（ADHD）和精神分裂症的临床研究具有重要意义，在这些研究中，已经证明眼动剂异常。