Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK; Sainsbury Wellcome Centre, University College London, London W1T 4JG, UK.
Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK; Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK.
Neuron. 2024 Jul 17;112(14):2386-2403.e6. doi: 10.1016/j.neuron.2024.04.015. Epub 2024 May 9.
To investigate which activity patterns in sensory cortex are relevant for perceptual decision-making, we combined two-photon calcium imaging and targeted two-photon optogenetics to interrogate barrel cortex activity during perceptual discrimination. We trained mice to discriminate bilateral whisker deflections and report decisions by licking left or right. Two-photon calcium imaging revealed sparse coding of contralateral and ipsilateral whisker input in layer 2/3, with most neurons remaining silent during the task. Activating pyramidal neurons using two-photon holographic photostimulation evoked a perceptual bias that scaled with the number of neurons photostimulated. This effect was dominated by optogenetic activation of non-coding neurons, which did not show sensory or motor-related activity during task performance. Photostimulation also revealed potent recruitment of cortical inhibition during sensory processing, which strongly and preferentially suppressed non-coding neurons. Our results suggest that a pool of non-coding neurons, selectively suppressed by network inhibition during sensory processing, can be recruited to enhance perception.
为了探究感觉皮层中的哪些活动模式与知觉决策有关，我们结合双光子钙成像和靶向双光子光遗传学技术，在知觉辨别过程中探究了皮层活动。我们训练小鼠辨别双侧胡须的偏移，并通过左右舔舐来报告决策。双光子钙成像揭示了在 2/3 层中对侧和同侧胡须输入的稀疏编码，大多数神经元在任务期间保持沉默。使用双光子全息光刺激激活锥体神经元会引发与被光刺激的神经元数量成正比的知觉偏向。这种效应主要由非编码神经元的光遗传学激活所主导，这些神经元在任务执行过程中没有表现出感觉或运动相关的活动。光刺激还揭示了在感觉处理过程中皮质抑制的有力募集，这强烈且优先地抑制了非编码神经元。我们的结果表明，在感觉处理过程中被网络抑制选择性抑制的非编码神经元池可以被募集来增强感知。
