VLSM is a MATLAB toolbox for evaluating statistical relationships between damage to specific brain regions and resulting deficits. VLSM can be used for the analysis of both discrete and gradiated lesions (i.e. voxel-based morphometry), and in both cases incorporates permutation tests for robust assessment of statistical significance.
VLSM is described in the following papers:
Bates E, Wilson SM, Saygin AP, Dick F, Sereno MI, Knight RT, Dronkers NF. Voxel-based lesion-symptom mapping. Nat Neurosci 2003; 6: 448-50. [pdf]
Wilson SM, Henry ML, Besbris M, Ogar JM, Dronkers NF, Jarrold W, Miller BL, Gorno-Tempini ML. Connected speech production in three variants of primary progressive aphasia. Brain 2010; 133: 2069-88. [pdf]