视觉拥挤效应的神经机制

当出现在边缘视野的一个物体被周围其他物体包围时,视觉系统对它的识别会很困难,这种现象叫做视觉拥挤效应.研究拥挤效应既有利于理解人类进行客体识别的过程,也对治疗黄斑变性、弱视和阅读障碍等视觉病变有显著的临床意义.自拥挤效应被提出以来,对拥挤效应的特性、神经机制和影响因素等都做了深入地研究.本文将系统地综述拥挤效应的研究进展,包括其特性、现有的理论假设、计算模型、可能涉及的大脑区域以及近年来利用知觉学习消除拥挤效应的一些工作,最后对该领域的未来发展给出建议.尽管在这个领域已经获得了丰富的成果,但在许多问题上仍有争议,未来还需要更为巧妙的设计和精确的技术进一步解决这些问题.

Neural Mechanisms of Visual Crowding Effect

When a target is presented with nearby flankers in the peripheral visual field, it becomes difficult to be identified, which is a phenomenon termed crowding. Studying crowding not only facilitates understanding of object recognition, but also benefits the remedy of macular degeneration, amblyopia and dyslexia. Since the concept of crowding was put forward, researchers have studied it extensively and gained much knowledge. Here, we provide an overview of the advances in this research field, including the properties of crowding, the existing theories and computational models that were proposed to explain the underlying neural mechanisms of crowding and how to alleviate crowding with perceptual learning. Although there has been tremendous growth of this topic, controversies remain. Further studies with elaborate designs and advanced technologies are required to address these controversies.