1. Representational similarity analysis based on the Euclidean distance.
Representational similarity analysis based on the Euclidean distance. A, Mean similarity matrix across subjects of multivariate fMRI responses in rFFA for different rotational angles for faces. B, We compared empirical similarity matrices with three models: monotonic model, mirror-symmetric model, and mirrored version of the monotonic model. Significant correlations with the data were observed for the monotonic and the mirror-symmetric models (p values: exact sign-permutation tests). The mirrored monotonic model was not significantly correlated with the data. Because the monotonic model is partially correlated to the mirror-symmetric model, conclusive evidence for mirror symmetry would require that the mirror-symmetric model outperforms the monotonic model. C, The mirror-symmetric model did not outperform the monotonic model.
Fernando M. Ramírez et al. J. Neurosci. 2014;34:
©2014 by Society for Neuroscience