Animal Physiology Unit, Institute of Neurobiology, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany.
Animal Physiology Unit, Institute of Neurobiology, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany.
Cell Rep. 2021 Aug 3;36(5):109470. doi: 10.1016/j.celrep.2021.109470.
Feature-based attention enables privileged processing of specific visual properties. During feature-based attention, neurons in visual cortices show "gain modulation" by enhancing neuronal responses to the features of attended stimuli due to top-down signals originating from prefrontal cortex (PFC). Attentional modulation in visual cortices requires "feature similarity:" neurons only increase their responses when the attended feature variable and the neurons' preferred feature coincide. However, whether gain modulation based on feature similarity is a general attentional mechanism is currently unknown. To address this issue, we record single-unit activity from PFC of macaques trained to switch attention between two conjunctive feature parameters. We find that PFC neurons experience gain modulation in response to attentional demands. However, this attentional gain modulation in PFC is independent of the feature-tuning preferences of neurons. These findings suggest that feature similarity is not a general mechanism in feature-based attention throughout the cortical processing hierarchy.
基于特征的注意力使特定视觉属性能够得到优先处理。在基于特征的注意力过程中，由于来自前额叶皮层 (PFC) 的自上而下的信号，视觉皮层中的神经元会通过增强对注意刺激特征的神经元反应来表现出“增益调制”。视觉皮层中的注意力调制需要“特征相似性”：只有当注意特征变量与神经元的最佳特征相同时，神经元才会增加其反应。然而，基于特征相似性的增益调制是否是一种普遍的注意力机制目前尚不清楚。为了解决这个问题，我们记录了经过训练以在两个联合特征参数之间切换注意力的猕猴 PFC 的单个单元活动。我们发现 PFC 神经元会根据注意力需求经历增益调制。然而，PFC 中的这种注意力增益调制与神经元的特征调谐偏好无关。这些发现表明，特征相似性不是整个皮质处理层次结构中基于特征的注意力的一般机制。
