Neural Correlates of Language and Communication in Apes

描述(申请人提供)：拟议研究的长期目标是了解早期环境在手动手势和面部表情不对称的发展中所起的作用，以及它们与大脑不同结构的关系。在这项拟议的研究中，对手势交流中使用的功能不对称和参考发声时使用的面部表情的行为研究将与磁共振成像(MRI)评估的神经解剖不对称相关。具体地说，手势的使用是否代表了一种独特的功能不对称，或者它是否反映了所有运动功能的普遍不对称，将通过比较手势的利手指数与具有类似情景要求的运动任务来评估。在另一系列实验中，将评估语音交流对指代手势手势表达的影响，以确定语音信号是增强还是抑制交流行为中不对称的程度。在第三组实验中，具有参照功能的黑猩猩做出的面部表情的不对称性将与没有使用参照发声的面部表情的不对称性进行比较。最后，手势交流和面部表情的偏侧性将与大脑特定感兴趣区的不对称性相关，这些感兴趣区包括颞平面、中央前回的运动/手区、扣带回和基底节。此外，还将使用扩散张量成像(DTI)评估和比较大脑半球之间皮质连接性的不对称性。在所有分析中特别感兴趣的将是将由人类饲养并接触人类语言的类人猿对象与由同种物种饲养的类人猿对象进行比较。这种比较将有助于确定人类环境和通信系统可能如何改变黑猩猩和黑猩猩的交流行为和大脑组织的发展。总体而言，拟议的研究将有助于更好地理解影响中枢神经系统发育的因素及其行为和交际相关性。

DESCRIPTION (provided by applicant): The long-term objectives of the proposed studies are to understand the role that early environment plays in the development of asymmetries in manual gestures and facial expressions and their relationship to different structures of the brain. In the proposed research, behavioral studies on functional asymmetries in hand use for gestural communication and facial expressions used with referential vocalizations will be correlated with neuroanatomical asymmetries as assessed by magnetic resonance imaging (MRI). Specifically, whether hand use for gestures represents a unique functional asymmetry or whether it reflects a general asymmetry for all motor functions will be assessed by comparing handedness indices for gestures compared to motor tasks with similar situational demands. In another series of experiments, the influence of vocal communication on the expression of hand use for referential gestures will be assessed to determine whether the vocal signals enhance or inhibit the magnitude of asymmetries in communicative behavior. In a third set of experiments, asymmetries in facial expressions that made by bonobos that have a referential function will be compared to asymmetries in facial expressions that are not accompanied by the use of a referential vocalization. Finally, laterality in gestural communication and facial expressions will be correlated with asymmetries in the brain from specific regions of interest including the planum temporale, motor/hand area of the precentral gyrus, cingulate gyrus and basal ganglia. In addition, asymmetries in cortical connectivity using diffusion tensor imaging (DTI) will be assessed and compared between hemispheres. Of specific interest in all analyses will be the comparison of ape subjects that have been reared by humans and exposed to human language compared to those reared by conspecifics. This comparison will allow for determination of how human environments and communication systems may alter the development of communicative behavior and the cerebral organization of bonobos and chimpanzees. Overall, the proposed research will lead a better understanding of factors which influence the development of the central nervous system and its behavioral and communicative correlates.