Studies show that manipulating certain training features in perceptual
learning determines the specificity of the improvement. The improvement in
abnormal visual processing following training and its generalization to visual
acuity, as measured on static clinical charts, can be explained by improved
sensitivity or processing speed. Crowding, the inability to recognize objects
in a clutter, fundamentally limits conscious visual perception. Although it
was largely considered absent in the fovea, earlier studies report foveal
crowding upon very brief exposures or following spatial manipulations. Here we
used GlassesOff's application for iDevices to train foveal vision of young
participants. The training was performed at reading distance based on contrast
detection tasks under different spatial and temporal constraints using Gabor
patches aimed at testing improvement of processing speed. We found several
significant improvements in spatio-temporal visual functions including near
and also non-trained far distances. A remarkable transfer to visual acuity
measured under crowded conditions resulted in reduced processing time of 81
ms, in order to achieve 6/6 acuity. Despite a subtle change in contrast
sensitivity, a robust increase in processing speed was found. Thus, enhanced
processing speed may lead to overcoming foveal crowding and might be the
enabling factor for generalization to other visual functions
