Psychology Department, University of California, San Diego, La Jolla, CA 92093-0109, USA.
J Cogn Neurosci. 2010 Nov;22(11):2460-79. doi: 10.1162/jocn.2009.21373.
We examined the organization and function of the ventral object processing pathway. The prevailing theoretical approach in this field holds that the ventral object processing stream has a modular organization, in which visual perception is carried out in posterior regions and visual memory is carried out, independently, in the anterior temporal lobe. In contrast, recent work has argued against this modular framework, favoring instead a continuous, hierarchical account of cognitive processing in these regions. We join the latter group and illustrate our view with simulations from a computational model that extends the perceptual-mnemonic feature-conjunction model of visual discrimination proposed by Bussey and Saksida [Bussey, T. J., & Saksida, L. M. The organization of visual object representations: A connectionist model of effects of lesions in perirhinal cortex. European Journal of Neuroscience, 15, 355-364, 2002]. We use the extended model to revisit early data from Iwai and Mishkin [Iwai, E., & Mishkin, M. Two visual foci in the temporal lobe of monkeys. In N. Yoshii & N. Buchwald (Eds.), Neurophysiological basis of learning and behavior (pp. 1-11). Japan: Osaka University Press, 1968]; this seminal study was interpreted as evidence for the modularity of visual perception and visual memory. The model accounts for a double dissociation in monkeys' visual discrimination performance following lesions to different regions of the ventral visual stream. This double dissociation is frequently cited as evidence for separate systems for perception and memory. However, the model provides a parsimonious, mechanistic, single-system account of the double dissociation data. We propose that the effects of lesions in ventral visual stream on visual discrimination are due to compromised representations within a hierarchical representational continuum rather than impairment in a specific type of learning, memory, or perception. We argue that consideration of the nature of stimulus representations and their processing in cortex is a more fruitful approach than attempting to map cognition onto functional modules.
我们研究了腹侧物体处理通路的组织和功能。该领域的主流理论观点认为，腹侧物体处理流具有模块化组织，其中视觉感知在后区进行，而视觉记忆则在前颞叶独立进行。相比之下，最近的研究工作反对这种模块化框架，而是支持这些区域认知处理的连续、分层的解释。我们加入了后一组，并通过对视觉辨别知觉-记忆特征结合模型的扩展计算模型的模拟来说明我们的观点，该模型由 Bussey 和 Saksida 提出 [Bussey, T. J., & Saksida, L. M. The organization of visual object representations: A connectionist model of effects of lesions in perirhinal cortex. European Journal of Neuroscience, 15, 355-364, 2002]。我们使用扩展模型重新审视了 Iwai 和 Mishkin 的早期数据 [Iwai, E., & Mishkin, M. Two visual foci in the temporal lobe of monkeys. In N. Yoshii & N. Buchwald (Eds.), Neurophysiological basis of learning and behavior (pp. 1-11). Japan: Osaka University Press, 1968]；这项开创性的研究被解释为视觉感知和视觉记忆模块化的证据。该模型解释了猴子在腹侧视觉流的不同区域受损后视觉辨别表现的双重分离。这种双重分离经常被引用为感知和记忆系统分离的证据。然而，该模型提供了一个简洁、机械的单系统对双重分离数据的解释。我们提出，腹侧视觉流损伤对视觉辨别能力的影响是由于分层表示连续体中的表示受损，而不是特定类型的学习、记忆或感知受损。我们认为，考虑刺激表示的性质及其在皮层中的处理是比试图将认知映射到功能模块更有成效的方法。
