Perceptual learning for global motion is tuned for spatial frequency.
Date:
This project was funded by ESSEXLab
Perceptual learning research routinely demonstrates that improvements exhibit a high degree of specificity to the trained stimulus. A recent study by Levi, Shaked, Tadin, & Huxlin (2015), observed an improvement in contrast sensitivity as a result of training on global motion stimuli. This study sought to further investigate this generalisation of learning. Participants trained daily, for five continuous days, on one of three global motion tasks (broadband, low or high frequency random-dot gabors) with auditory trial-by-trial feedback. Additionally participants completed a pre and post training assessment consisting of all three levels of global motion (without feedback) as well as high and low spatial frequency contrast sensitivity tasks. Perceptual learning, during the five days training, occurred for low, and to a lesser extent for broad frequency conditions, but no improvement was found in the high frequency condition. Comparisons of pre and post assessments found improvement exclusively in the low frequency global motion condition. Furthermore, there was no transfer of learning between global motion stimuli. Finally, there was no improvement in contrast sensitivity for any trained frequency. This suggests that global motion training may not improve contrast sensitivity, and improvements at the visual level occur only with low frequency global motion tasks.