Features of the second-order visual filters sensitive to the spatial frequency modulations

TL;DR

This study explores the selectivity of second-order visual filters to spatial frequency modulations, revealing their sensitivity to SF of modulation but not to orientation, suggesting concentric receptive fields.

Contribution

It provides new psychophysical evidence on the selectivity of second-order visual filters to SF of modulation and their non-selectivity to orientation.

Findings

Second-order filters are selective to SF of modulation with a bandwidth of +1.5 octaves.

They do not show selectivity to the orientation of modulation.

Receptive fields of these mechanisms are likely concentric.

Abstract

We investigated selectivity of 2nd order visual filters sensitive to the spatial frequency (SF) modulations to orientation and to SF of modulation. We carried out psychophysical experiment using masking paradigm. It was found that 2nd order filters are selective to SF of modulation (with bandwidth +1.5 octaves), and do not show any selectivity to orientation of modulation. We suppose receptive fields of 2nd order mechanisms have concentric form.