Baumann Oliver, Mattingley Jason B
Queensland Brain Institute and
Queensland Brain Institute and School of Psychology, The University of Queensland, St Lucia 4072, Australia.
J Neurosci. 2016 Feb 24;36(8):2536-42. doi: 10.1523/JNEUROSCI.3368-15.2016.
The human parahippocampal cortex has been ascribed central roles in both visuospatial and mnemonic processes. More specifically, evidence suggests that the parahippocampal cortex subserves both the perceptual analysis of scene layouts as well as the retrieval of associative contextual memories. It remains unclear, however, whether these two functional roles can be dissociated within the parahippocampal cortex anatomically. Here, we provide evidence for a dissociation between neural activation patterns associated with visuospatial analysis of scenes and contextual mnemonic processing along the parahippocampal longitudinal axis. We used fMRI to measure parahippocampal responses while participants engaged in a task that required them to judge the contextual relatedness of scene and object pairs, which were presented either as words or pictures. Results from combined factorial and conjunction analyses indicated that the posterior section of parahippocampal cortex is driven predominantly by judgments associated with pictorial scene analysis, whereas its anterior section is more active during contextual judgments regardless of stimulus category (scenes vs objects) or modality (word vs picture). Activation maxima associated with visuospatial and mnemonic processes were spatially segregated, providing support for the existence of functionally distinct subregions along the parahippocampal longitudinal axis and suggesting that, in humans, the parahippocampal cortex serves as a functional interface between perception and memory systems.
人类海马旁回皮质在视觉空间和记忆过程中都被认为起着核心作用。更具体地说，有证据表明，海马旁回皮质既有助于对场景布局进行感知分析，也有助于提取关联性情境记忆。然而，目前尚不清楚这两种功能在海马旁回皮质的解剖结构上是否能够分离。在此，我们提供证据表明，在海马旁回皮质纵轴上，与场景的视觉空间分析和情境记忆处理相关的神经激活模式存在分离。我们使用功能磁共振成像（fMRI）来测量海马旁回的反应，同时让参与者执行一项任务，要求他们判断以文字或图片形式呈现的场景和物体对的情境相关性。联合因子分析和联合分析的结果表明，海马旁回皮质的后部主要由与图片场景分析相关的判断驱动，而其前部在情境判断过程中更为活跃，无论刺激类别（场景与物体）或形式（文字与图片）如何。与视觉空间和记忆过程相关的激活最大值在空间上是分离的，这为海马旁回皮质纵轴上存在功能不同的子区域提供了支持，并表明在人类中，海马旁回皮质充当了感知和记忆系统之间的功能接口。
