Median cell selectivity and population sparseness of tensorfaces as a function of tensorface rank. Responses are from 100 tensorfaces stimulated by the 128 faces in the sample set. Cell selectivity and population sparseness are both calculated as kurtosis of the probability distribution of responses. Cell selectivity refers to sparseness of single neurons calculated to a set of stimuli presented over time (also called lifetime sparseness). Population sparseness refers to population response to a single stimulus. The shaded area shows interquartile range. (a) Cell selectivity. (b) Population sparseness.