Boronat Consuelo B, Buxbaum Laurel J, Coslett H Branch, Tang Kathy, Saffran Eleanor M, Kimberg Daniel Y, Detre John A
Moss Rehabilitation Research Institute, Korman 213, 1200 W. Tabor Rd., Philadelphia, PA 19141, USA.
Brain Res Cogn Brain Res. 2005 May;23(2-3):361-73. doi: 10.1016/j.cogbrainres.2004.11.001. Epub 2005 Jan 7.
A prominent account of conceptual knowledge proposes that information is distributed over visual, tactile, auditory, motor and verbal-declarative attribute domains to the degree to which these features were activated when the knowledge was acquired [D.A. Allport, Distributed memory, modular subsystems and dysphagia, In: S.K. Newman, R. Epstein (Eds.), Current perspectives in dysphagia, Churchill Livingstone, Edinburgh, 1985, pp. 32-60]. A corollary is that when drawing upon this knowledge (e.g., to answer questions), particular aspects of this distributed information is re-activated as a function of the requirements of the task at hand [L.J. Buxbaum, E.M. Saffran, Knowledge of object manipulation and object function: dissociations in apraxic and non-apraxic subjects. Brain and Language, 82 (2002) 179-199; L.J. Buxbaum, T. Veramonti, M.F. Schwartz, Function and manipulation tool knowledge in apraxia: knowing 'what for' but not 'how', Neurocase, 6 (2000) 83-97; W. Simmons, L. Barsalou, The similarity-in-topography principle: Reconciling theories of conceptual deficits, Cognitive Neuropsychology, 20 (2003) 451-486]. This account predicts that answering questions about object manipulation should activate brain regions previously identified as components of the distributed sensory-motor system involved in object use, whereas answering questions about object function (that is, the purpose that it serves) should activate regions identified as components of the systems supporting verbal-declarative features. These predictions were tested in a functional magnetic resonance imaging (fMRI) study in which 15 participants viewed picture or word pairs denoting manipulable objects and determined whether the objects are manipulated similarly (M condition) or serve the same function (F condition). Significantly greater and more extensive activations in the left inferior parietal lobe bordering the intraparietal sulcus were seen in the M condition with pictures and, to a lesser degree, words. These findings are consistent with the known role of this region in skilled object use [K.M. Heilman, L.J. Gonzalez Rothi, Apraxia, In: K.M. Heilman, E. Valenstein (Eds.), Clinical Neuropsychology, Oxford University Press, New York, 1993, pp. 141-150] as well as previous fMRI results [M. Kellenbach, M. Brett, K. Patterson, Actions speak louder than functions: the importance of manipulability and action in tool representation, Journal of Cognitive Neuroscience, 15 (2003) 30-46] and behavioral findings in brain-lesion patients [L.J. Buxbaum, E.M. Saffran, Knowledge of object manipulation and object function: dissociations in apraxic and non-apraxic subjects, Brain and Language, 82 (2002) 179-199]. No brain regions were significantly more activated in the F than M condition. These data suggest that brain regions specialized for sensory-motor function are a critical component of distributed representations of manipulable objects.
一种关于概念知识的重要观点认为，信息分布于视觉、触觉、听觉、运动以及言语陈述属性领域，其分布程度取决于知识获取时这些特征被激活的程度[D.A. 奥尔波特，《分布式记忆、模块化子系统与吞咽困难》，载于：S.K. 纽曼、R. 爱泼斯坦（编），《吞咽困难的当前观点》，丘吉尔·利文斯通出版社，爱丁堡，1985年，第32 - 60页]。一个必然结果是，当利用这些知识时（例如回答问题），根据手头任务的要求，这些分布式信息的特定方面会被重新激活[L.J. 布克斯鲍姆、E.M. 萨夫兰，《物体操作知识与物体功能知识：失用症患者与非失用症患者的分离》。《大脑与语言》，82（2002年）179 - 199；L.J. 布克斯鲍姆、T. 韦拉蒙蒂、M.F. 施瓦茨，《失用症中的功能与操作工具知识：知道“为何用”却不知“如何用”》，《神经病例》，6（2000年）83 - 97；W. 西蒙斯、L. 巴萨洛，《地形相似性原则：调和概念缺陷理论》，《认知神经心理学》，20（2003年）451 - 486]。这一观点预测，回答关于物体操作的问题应激活先前被确定为参与物体使用的分布式感觉运动系统组成部分的脑区，而回答关于物体功能（即其用途）的问题应激活被确定为支持言语陈述特征系统组成部分的脑区。这些预测在一项功能磁共振成像（fMRI）研究中得到了检验，在该研究中，15名参与者观看表示可操作物体的图片或单词对，并确定这些物体的操作方式是否相似（M条件）或功能是否相同（F条件）。在M条件下，观看图片时，左顶下叶靠近顶内沟处出现了显著更大范围和更广泛的激活，观看单词时激活程度稍低。这些发现与该区域在熟练物体使用中的已知作用相符[K.M. 海尔曼、L.J. 冈萨雷斯·罗西，《失用症》，载于：K.M. 海尔曼、E. 瓦伦斯坦（编），《临床神经心理学》，牛津大学出版社，纽约，1993年，第141 - 150页]，也与先前的fMRI结果相符[M. 凯伦巴赫、M. 布雷特、K. 帕特森，《行动比功能更响亮：可操作性和行动在工具表征中的重要性》，《认知神经科学杂志》，15（2003年）30 - 46]以及脑损伤患者的行为学发现相符[L.J. 布克斯鲍姆、E.M. 萨夫兰，《物体操作知识与物体功能知识：失用症患者与非失用症患者的分离》，《大脑与语言》，82（2002年）179 - 199]。在F条件下，没有脑区比M条件下有更显著的激活。这些数据表明，专门用于感觉运动功能的脑区是可操作物体分布式表征的关键组成部分。
