Appearances of stable t-f components in each individual rat subject. (a) Stable t-f components detected in each individual subject: a white block means the corresponding t-f component can be identified in this subject, while a black block means this component cannot be found in this subject. The numbers in brackets after the component names are the appearances of components, while the numbers in brackets below the subject number are the number of components detected in this subject. (b) Histogram of appearances of stable t-f components. (c) Histogram of number of stable t-f components detected in one subject.