Goel Vinod
Department of Psychology, York University, Toronto, ON, Canada; Department of Psychology, Capital Normal University, Beijing, China.
Handb Clin Neurol. 2019;163:179-196. doi: 10.1016/B978-0-12-804281-6.00010-0.
With the exception of language, hemispheric asymmetry has not historically been an important issue in the frontal lobe literature. Data generated over the past 20 years is forcing a reconsideration of this position. There is now considerable evidence to suggest that the left prefrontal cortex is an inference engine that automatically makes simple conceptual, logical, and causal connections to fill in missing information and eliminate uncertainty or indeterminacy. This is a fine-tuning of the "left hemisphere interpreter" account from the callosotomy patient literature. What is new is an understanding of the important contributions of the right prefrontal cortex to formal logical inference, conflict detection, and indeterminacy tolerance and maintenance. This chapter articulates these claims and reviews the data on which they are based. The chapter concludes by speculating that the inference capabilities of the left prefrontal cortex are built into the very fabric of language and can be accounted for by the left hemisphere dominance for language. The roles of the right PFC require multiple mechanisms for explanation. Its role in formal inference may be a function of its visual-spatial processing capabilities. Its role in conflict detection may be explained as a system for checking for consistency between existing beliefs and new information coming into the system and inferences drawn from beliefs and/or new information. There are at least three possible mechanisms to account for its role in indeterminacy tolerance. First, it could contain a representational system with properties very different from those of language, and an accompanying inference engine. Second, it could just contain this different representational system, and the information is at some point passed back to the left prefrontal cortex for inference. Third, the role of the right prefrontal cortex may be largely preventative. That is, it doesn't provide alternative representational and inference capabilities but simply prevents the left prefrontal cortex from settling on initial, local inferences. The current data do not allow differentiating between these possibilities. Successful real-world functioning requires the participation of both hemispheres.
除语言外，半球不对称性在额叶文献中历来不是一个重要问题。过去20年产生的数据促使人们重新审视这一观点。现在有大量证据表明，左侧前额叶皮质是一个推理引擎，它能自动建立简单的概念、逻辑和因果联系，以填补缺失信息并消除不确定性或不明确性。这是对胼胝体切开术患者文献中“左半球解释器”观点的微调。新的认识是，右侧前额叶皮质对形式逻辑推理、冲突检测以及不确定性容忍和维持具有重要贡献。本章阐述了这些观点，并回顾了其依据的数据。本章最后推测，左侧前额叶皮质的推理能力是语言结构所固有的，并且可以用左半球在语言方面的优势来解释。右侧前额叶皮质的作用需要多种机制来解释。它在形式推理中的作用可能是其视觉空间处理能力的一种功能。它在冲突检测中的作用可以解释为一个用于检查现有信念与进入系统的新信息以及从信念和/或新信息得出的推理之间一致性的系统。至少有三种可能的机制来解释其在不确定性容忍中的作用。首先，它可能包含一个与语言属性非常不同的表征系统以及一个伴随的推理引擎。其次，它可能只包含这个不同的表征系统，并且信息在某个时候会传回左侧前额叶皮质进行推理。第三，可以解释为右侧前额叶皮质的作用在很大程度上是预防性的。也就是说，它不提供替代的表征和推理能力，而只是防止左侧前额叶皮质确定初始的局部推理。目前的数据无法区分这些可能性。在现实世界中成功发挥功能需要两个半球的参与。
