Spatial interactions in human vision: from near to farvia experience-dependent cascades of connections.

TLDR

Perceptual learning has been shown to affect early visual processes. Here, we show that learning induces an increase in the spatial range of lateral interactions. Using a lateral masking/facilitation paradigm with bandpass‑localized stimuli, we measured interaction range before and after extensive training on a threshold detection task, suggesting that longer‑range facilitation arises from internal response transmission via a cascade of local connections. Naïve observers showed mask‑induced facilitation up to six times the target period, but practice increased this range by at least threefold, the chain can be broken, and the results indicate Hebbian‑like plasticity in early vision.

Abstract

Perceptual learning has been shown to affect early visual processes. Here, we show that learning induces an increase in the spatial range of lateral interactions. Using a lateral masking/facilitation paradigm and bandpass-localized stimuli, we measured the interaction range before and after extensive training on a threshold detection task. For naive observers, target threshold was found to be facilitated by mask presence at distances up to six times the target period. However, practice had the effect of increasing the facilitation range by at least a factor of three. We suggest that the induced longer-range facilitation is a result of internal response transmission via a cascade of local connections. The data presented also show that this chain can be broken. These results suggest a plasticity in early vision governed by Hebbian-like rules.