Target-selective tilt aftereffect during texture learning

Abstract

Sensory adaptation and perceptual learning are two forms of plasticity in the visual system, with some potential overlapping neural mechanisms and functional benefits. However, they have been largely considered in isolation. Here we examined whether extensive perceptual training with oriented textures (texture discrimination task, TDT) induces adaptation tilt aftereffects (TAE). Texture elements were oriented lines at -22.5° (target) and 22.5° (background). Observers were trained in 5 daily sessions on the TDT, with 800-1000trials/session. Thresholds increased within the daily sessions, showing within-session performance deterioration, but decreased between days, showing learning. To evaluate TAE, perceived vertical (0°) was measured prior to and after each daily session using a single line element. The results showed a TAE of ∼1.5° at retinal locations consistently stimulated by the target, but none at locations consistently stimulated by the background texture. Retinal locations equally stimulated by target and background elements showed a significant TAE (∼0.7°), in a direction expected by target-driven sensory adaptation. Moreover, these locations showed increasing TAE persistence with training. Additional experiments with a modified target, in order to have balanced stimulation around the vertical direction in all target locations, confirmed the locality of the task-dependent TAE. The present results support a strong link between perceptual learning and local orientation-selective adaptation leading to TAE; the latter was shown here to be task and experience dependent.

Direction selective habituation of motion adaptation

“…Unlike other studies of perceptual learning affecting adaptation (Haak et al, 2014;McGovern et al, 2012;Pinchuk-Yacobi et al, 2016;Yehezkel et al, 2010), where increased or unchanged adaptation effects were observed after training, we found decreased adaptation effects over training. Note that the current experimental design differs from theirs in several aspects.…”

“…For example, adaptation to contrast reduction or distortion strengthens after viewing the altered visual environment for a few days (Haak, Fast, Bao, Lee, & Engel, 2014;Yehezkel, Sagi, Sterkin, Belkin, & Polat, 2010). Furthermore, the persistence of tilt aftereffect induced by texture discrimination task increases with training (Pinchuk-Yacobi, Harris, & Sagi, 2016). However, there are also exceptions.…”

Orientation-selective adaptation improves perceptual grouping

“…Most importantly, exposure to stimuli with 45° offset orientation, as in the ‘Vertical’ and ‘Mixed’ blocks, resulted in a significant deterioration of performance, rather than improvement. This result is in accordance with the adaptation literature showing de-adaptation for stimuli offset by 45° (Greenlee & Magnussen, 1988; Harris et al, 2012; Pinchuk-Yacobi, Harris, & Sagi, 2016)(Greenlee & Magnussen, 1988; Harris et al, 2012).…”

A dissociation between consolidated perceptual learning and sensory adaptation in vision

“…Thus, following initial encoding of the visual memory, it undergoes stabilization or enhancement evident as offline gains in performance2567. In addition, while perceptual learning is based on repeated training, previous studies have shown that over-exposure to the task results in performance deterioration8910, possibly involving adaptation-related mechanisms111213. Thus, such previous studies have challenged the traditional view according to which ‘practice makes perfect’, showing that increasing task exposure can reduce performance, and interfere with consolidation of efficient learning mechanisms.…”