Department of Ophthalmology, University Medical Center Göttingen, 37073 Göttingen, Germany; Bernstein Center for Computational Neuroscience Göttingen, 37077 Göttingen, Germany.
Department of Ophthalmology, University Medical Center Göttingen, 37073 Göttingen, Germany; Bernstein Center for Computational Neuroscience Göttingen, 37077 Göttingen, Germany.
Neuron. 2019 Mar 6;101(5):963-976.e7. doi: 10.1016/j.neuron.2019.01.003. Epub 2019 Jan 29.
Neurons in sensory systems are often tuned to particular stimulus features. During complex naturalistic stimulation, however, multiple features may simultaneously affect neuronal responses, which complicates the readout of individual features. To investigate feature representation under complex stimulation, we studied how direction-selective ganglion cells in salamander retina respond to texture motion where direction, velocity, and spatial pattern inside the receptive field continuously change. We found that the cells preserve their direction preference under this stimulation, yet their direction encoding becomes ambiguous due to simultaneous activation by luminance changes. The ambiguities can be resolved by considering populations of direction-selective cells with different preferred directions. This gives rise to synergistic motion decoding, yielding more information from the population than the summed information from single-cell responses. Strong positive response correlations between cells with different preferred directions amplify this synergy. Our results show how correlated population activity can enhance feature extraction in complex visual scenes.
感觉系统中的神经元通常对特定的刺激特征敏感。然而，在复杂的自然刺激下，多个特征可能同时影响神经元的反应，这使得对单个特征的解读变得复杂。为了研究复杂刺激下的特征表示，我们研究了蝾螈视网膜中的方向选择性神经节细胞如何对纹理运动做出反应，其中感受野内的方向、速度和空间模式不断变化。我们发现，在这种刺激下，细胞保持其方向偏好，但由于同时受到亮度变化的激活，其方向编码变得模糊。通过考虑具有不同最佳方向的方向选择性细胞群体，可以解决这些模糊性。这导致协同运动解码，从群体中获得的信息比单个细胞反应的总和信息更多。具有不同最佳方向的细胞之间的强正响应相关性增强了这种协同作用。我们的结果表明，相关的群体活动如何在复杂的视觉场景中增强特征提取。
