Single neuron feature selectivity index (FSI), a measure of how sensitive a neuron is to changes in each feature value separately. A: A1: a positive correlation between AM and ΔBW selectivity (Pearson rho = 0.3143, P = 0.002). B: ML: positive correlation between AM and BW selectivity (Pearson’s rho = 0.3109, P = 5.32 e-4). AM, amplitude modulation; A1, primary auditory cortex; BW, bandwidth; ML, middle lateral belt; ΔBW, bandwidth restricted.