Fig. 5. ImageNet category-selective units in untrained networks.

a The responses of units in untrained networks to the images of 1000 ImageNet⁶⁵ classes and to face images (VGGFace2)⁶². b Average tuning curve of gazania selective units. (Inset) Responses of gazania-selective units to the original gazania (n = 100), the scrambled gazania (n = 100) and texform gazania images (n = 100). c The number of selective units for 39 classes in which selective units are observed. The error bar indicates the standard deviation of 50 random networks. d Sample preferred feature images achieved by reverse-correlation analysis and stimulus images (inset). e Visualization of the PCA (principal component analysis)⁷⁸ analysis results (only two principal components (PC) are shown) using the Conv5 unit responses to each class in untrained networks. The analysis was performed using 3999 principal components, and the top 140 ± 32 components contained 75% of the variance. f The silhouette index⁷⁹ of the Conv5 unit responses was measured using all principal components to estimate the consistency of data clustering. Each dot indicates the mean and the error bar indicates the standard deviation of 50 simulations of randomly initialized networks. The error bar indicates the standard deviation of 50 simulations of randomly initialized networks. g Correlation between the silhouette index and the number of selective units observed (Pearson correlation). Each dot indicates the mean and the error bar indicates the standard deviation of 50 random networks. All box plots indicate the inter-quartile range (IQR between Q1 and Q3) of the dataset, the horizontal line depicts the median and the whiskers correspond to the rest of the distribution (Q1 − 1.5*IQR, Q3 + 1.5*IQR). For copyright reasons, the images in panels (a) and (d) are not the actual images used in the experiments. The original images are replaced with images with similar contents for display purposes. The original images are available at [https://www.image-net.org/download, https://arxiv.org/abs/1710.08092]. Images shown are available at [https://www.shutterstock.com] (see Methods for details).