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Recent discoveries indicate that the neural codes in the superficial layers of the primary visual cortex (V1) of macaque monkeys are complex, diverse, and super-sparse. This leads us to ponder the computational advantages and functional role of these “grandmother cells." Here, we propose that such cells can serve as prototype memory priors that bias and shape the distributed feature processing during the image generation process in the brain. These memory prototypes are learned by momentum online clustering and are utilized through a memory-based attention operation. Integrating this mechanism, we propose Memory Concept Attention (MoCA) to improve few-shot image generation quality. We show that having a prototype memory with attention mechanisms can improve image synthesis quality, learn interpretable visual concept clusters, and improve the robustness of the model. Our results demonstrate the feasibility of the idea that these super-sparse complex feature detectors can serve as prototype memory priors for modulating the image synthesis processes in the visual system 

System identification techniques—projection pursuit regression models (PPRs) and convolutional neural networks (CNNs)—provide state-of-the-art performance in predicting visual cortical neurons’ responses to arbitrary input stimuli. However, the constituent kernels recovered by these methods are often noisy and lack coherent structure, making it difficult to understand the underlying component features of a neuron’s receptive field. In this paper, we show that using a dictionary of diverse kernels with complex shapes learned from natural scenes based on efficient coding theory, as the front-end for PPRs and CNNs can improve their performance in neuronal response prediction as well as algorithmic data efficiency and convergence speed. Extensive experimental results also indicate that these sparse-code kernels provide important information on the component features of a neuron’s receptive field. In addition, we find that models with the complex-shaped sparse code front-end are significantly better than models with a standard orientation-selective Gabor filter front-end for modeling V1 neurons that have been found to exhibit complex pattern selectivity. We show that the relative performance difference due to these two front-ends can be used to produce a sensitive metric for detecting complex selectivity in V1 neurons.