Numerosity tuning in human association cortices and local image contrast representations in early visual cortex.

ABSTRACT: Human early visual cortex response amplitudes monotonically increase with numerosity (object number), regardless of object size and spacing. However, numerosity is typically considered a high-level visual or cognitive feature, while early visual responses follow image contrast in the spatial frequency domain. We find that, at fixed contrast, aggregate Fourier power (at all orientations and spatial frequencies) follows numerosity closely but nonlinearly with little effect of object size, spacing or shape. This would allow straightforward numerosity estimation from spatial frequency domain image representations. Using 7T fMRI, we show monotonic responses originate in primary visual cortex (V1) at the stimulus's retinotopic location. Responses here and in neural network models follow aggregat

SUBMITTER: Paul JM 

PROVIDER: S-EPMC8924234 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature