1. A computer implemented methodology for sound discrimination, comprising: receiving a training set of data; generating a cortical representation of the training set; computing a matrix decomposition using the cortical representation of the training set; receiving a plurality of regularization parameters; computing coefficients for each regularization parameter using the matrix decomposition; computing a leave-one-out (LOO) error for each of the regularization parameters; and selecting the regularization parameter with the lowest LOO error.