Low effective dimensionality of the human functional connectome does not invalidate lesion network mapping

Abstract

Van den Heuvel et al. argued that the low effective dimensionality of the human connectome causes lesion network maps to converge on a common pattern, the connectome degree map, and concluded that the method cannot resolve distinct symptom-specific circuits. Here, we show that, although lesion network maps are low-dimensional and biased towards the connectomes leading eigenvector, they still recover their ground-truth networks well. Moreover, we propose a modification of the connectome that at least halves this bias and can improve recovery. Our results, therefore, reaffirm the validity of lesion network mapping, while acknowledging the important limitations identified by its critics.