Analysis of the filter behavior.

Filter characteristics of the population code (red circle) and its best match with the Gabor function (gray circle) according to Eq. 2. The bandwidth (A) was quantified at -3 dB of the power spectrum maximum amplitude. The quality factor or sharpness (B) represents the ratio between the center frequency and bandwidth of the filters. The damping ratio (C) is a measure based on the quality factor and shows that the filters characteristics have underdamped () proprieties. The width of each filter temporal envelope (D) was measured at 3 dB below the peak of the energy power using the Hilbert transform.