Institute of Neuroscience, State Key Laboratory of Neuroscience, Chinese Academy of Sciences, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Center for Brain Science and Brain-Inspired Technology, Shanghai 200031, China; School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, China.
Institute of Neuroscience, State Key Laboratory of Neuroscience, Chinese Academy of Sciences, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Center for Brain Science and Brain-Inspired Technology, Shanghai 200031, China.
Neuron. 2020 Mar 4;105(5):934-946.e5. doi: 10.1016/j.neuron.2019.12.008.
Whether transient or sustained neuronal activity during the delay period underlies working memory (WM) has been debated. Here, we report that transient, but not sustained, delay-period activity in mouse anterior agranular insular cortex (aAIC) plays a dominant role in maintaining WM information during learning of novel olfactory tasks. By optogenetic screening over 12 brain regions, we found that suppressing aAIC activity markedly impaired olfactory WM maintenance during learning. Single-unit recording showed that odor-selective aAIC neurons with predominantly transient firing patterns encoded WM information. Both WM task performance and transient-neuron proportion were enhanced and reduced by activating and suppressing the delay-period activity of the projection from medial prefrontal cortex (mPFC) to aAIC. The ability of mice to resist delay-period distractors also correlated with an increased percentage of transient neurons. Therefore, transient, but not sustained, aAIC neuronal activity during the delay period is largely responsible for maintaining information while learning novel WM tasks.
在延迟期间短暂而非持续的神经元活动是否是工作记忆（WM）的基础一直存在争议。在这里，我们报告说，在学习新的嗅觉任务期间，小鼠前颗粒岛皮层（aAIC）中的短暂而非持续的延迟期活动在维持 WM 信息方面起着主导作用。通过对 12 个脑区进行光遗传学筛选，我们发现抑制 aAIC 活动会显著损害学习期间的嗅觉 WM 维持。单细胞记录显示，具有主要短暂放电模式的气味选择性 aAIC 神经元编码 WM 信息。通过激活和抑制从前扣带回皮层（mPFC）到 aAIC 的投射的延迟期活动，WM 任务表现和瞬时神经元比例都得到了增强和降低。小鼠抵抗延迟期干扰的能力也与瞬时神经元比例的增加相关。因此，在学习新的 WM 任务期间，延迟期间短暂而非持续的 aAIC 神经元活动在维持信息方面起着主要作用。
