Oliver Zoe J, Cristino Filipe, Roberts Mark V, Pegna Alan J, Leek E Charles
School of Psychology, Bangor University.
School of Psychology, University of Queensland.
J Exp Psychol Hum Percept Perform. 2018 Apr;44(4):518-534. doi: 10.1037/xhp0000444. Epub 2017 Oct 12.
The role of stereo disparity in the recognition of 3-dimensional (3D) object shape remains an unresolved issue for theoretical models of the human visual system. We examined this issue using high-density (128 channel) recordings of event-related potentials (ERPs). A recognition memory task was used in which observers were trained to recognize a subset of complex, multipart, 3D novel objects under conditions of either (bi-) monocular or stereo viewing. In a subsequent test phase they discriminated previously trained targets from untrained distractor objects that shared either local parts, 3D spatial configuration, or neither dimension, across both previously seen and novel viewpoints. The behavioral data showed a stereo advantage for target recognition at untrained viewpoints. ERPs showed early differential amplitude modulations to shape similarity defined by local part structure and global 3D spatial configuration. This occurred initially during an N1 component around 145-190 ms poststimulus onset, and then subsequently during an N2/P3 component around 260-385 ms poststimulus onset. For mono viewing, amplitude modulation during the N1 was greatest between targets and distracters with different local parts for trained views only. For stereo viewing, amplitude modulation during the N2/P3 was greatest between targets and distracters with different global 3D spatial configurations and generalized across trained and untrained views. The results show that image classification is modulated by stereo information about the local part, and global 3D spatial configuration of object shape. The findings challenge current theoretical models that do not attribute functional significance to stereo input during the computation of 3D object shape. (PsycINFO Database Record
立体视差在三维（3D）物体形状识别中的作用，对于人类视觉系统的理论模型来说仍是一个未解决的问题。我们使用高密度（128通道）事件相关电位（ERP）记录来研究这个问题。采用了一种识别记忆任务，其中观察者接受训练，在单眼或立体视觉条件下识别一组复杂、多部分的3D新奇物体。在随后的测试阶段，他们从先前未训练过的干扰物体中区分出先前训练过的目标，这些干扰物体在局部部分、3D空间配置或两个维度上均与目标不同，跨越先前见过的和新奇的视角。行为数据显示，在未训练的视角下，立体视觉对目标识别具有优势。ERP显示，对于由局部部分结构和全局3D空间配置定义的形状相似性，早期存在差异幅度调制。这种调制最初发生在刺激开始后约145 - 190毫秒的N1成分期间，随后发生在刺激开始后约260 - 385毫秒的N2/P3成分期间。对于单眼视觉，仅在训练视角下，N1期间目标与具有不同局部部分的干扰物之间的幅度调制最大。对于立体视觉，N2/P3期间目标与具有不同全局3D空间配置的干扰物之间的幅度调制最大，并且在训练和未训练的视角中均有体现。结果表明，图像分类受到关于物体形状的局部部分和全局3D空间配置的立体视觉信息的调制。这些发现挑战了当前的理论模型，这些模型在3D物体形状计算过程中未赋予立体视觉输入功能意义。（PsycINFO数据库记录）
