Cross-adaptation between first-order cartoon and real faces. Only the summary data from two naive subjects and two experimenters are shown. a, The test stimuli were always the cartoon faces. The adapting stimuli varied with conditions as follows: 0-cf, no-adaptation baseline; cf-cf, adaptation to the saddest cartoon face; rf-cf, adaptation to the saddest real face. b, The test stimuli were always the real faces. The adapting stimuli varied with conditions as follows: 0-rf, no-adaptation baseline; rf-rf, adaptation to the saddest real face; cf-rf, adaptation to the saddest cartoon face.