Cortical reorganization of peripheral vision induced by simulated central vision loss

Abstract

When one's central vision is deprived, a spared part of the peripheral retina acts as a pseudofovea for fixation. The neural mechanisms underlying this compensatory adjustment remain unclear. Here we report cortical reorganization induced by simulated central vision loss. Human subjects of both sexes learned to place the target at an eccentric retinal locus outside their blocked visual field for objecttracking. Before and after training, we measured visual crowding-a bottleneck of object identification in peripheral vision, using psychophysics and fMRI. We found that training led to an axis-specific reduction of crowding. The change of the crowding effect was reflected in the change of BOLD signal, as a release of cortical suppression in multiple visual areas starting as early as V1. Our findings suggest that the adult visual system is capable of reshaping its oculomotor control and sensory coding to adapt to impoverished visual input.

Combining fixation and lateral masking training enhances perceptual learning effects in patients with macular degeneration

“…Results showed that, overall, near visual acuity and crowding significantly improved in the untrained eye. These results are consistent with what observed in the trained eye and further suggest that training might have improved fixation stability, which, as mentioned in the previous subsection, seems to be related to both acuity and crowding ( Calabrèse et al, 2011 ; Chen et al, 2019 ; Crossland & Rubin, 2014 ; Tarita-Nistor, Brent, Steinbach, & González, 2011 ; Tarita-Nistor, González, Markowitz, & Steinbach, 2008 ; Timberlake et al, 2005 ).…”

“…Additionally, there is evidence linking fixation stability and peripheral VA and reading, both in MD patients ( Calabrèse et al, 2011 ; Crossland & Rubin, 2014 ; Tarita-Nistor, Brent, Steinbach, & González, 2011 ; Tarita-Nistor, González, Markowitz, & Steinbach, 2008 ; Timberlake et al, 2005 ) and participants trained with simulated scotoma ( Chen et al, 2019 ), and with the hypothesis that reading difficulties may depend on unstable fixation ( Falkenberg et al, 2007 ) and the suggestion of potential rehabilitative benefits of interventions based on fixation stability training ( Falkenberg et al, 2007 ).…”

Monocular and binocular end‐points after epiretinal membrane surgery and their correlation to patient‐reported outcomes

“…We hypothesized that patients with low ATR (≤5) have low plasticity and therefore are at risk of visual complaints if they are exposed to optical aniseikonia or distorted retinal images. The brain's plasticity to visual reinterpretation after retinal damage has been demonstrated in other studies (Dilks et al 2007;Bex 2010;Wiecek et al 2014;Wiecek et al 2015;Kingdom, Field & Olmos 2016;Chen et al 2019). By providing information on plasticity to aniseikonia in patients with ERM, ATR might help predict which patients are at risk of visual complaints due to optical/retinal aniseikonia or metamorphopsia due to low plasticity.…”

The Relationship Between Cognitive Status and Known Single Nucleotide Polymorphisms in Age-Related Macular Degeneration

“…The correlational relationship led to the sensory deprivation hypothesis, which states that a prolonged decline in sensory input will lead to cognitive decline due to neuronal atrophy (Valentijn et al, 2005;Clay et al, 2009). However, there is evidence to show to that vision impairment does lead to reorganization in the brain (Chen et al, 2019), but this is with respect to the processing of visual information, not memory and/or cognition. The few studies that have explored this hypothesis have not found results to support it (Hall et al, 2005;Anstey et al, 2006).…”