Active efficient coding explains the development of binocular vision and its failure in amblyopia

Abstract

The development of vision during the first months of life is an active process that comprises the learning of appropriate neural representations and the learning of accurate eye movements. While it has long been suspected that the two learning processes are coupled, there is still no widely accepted theoretical framework describing this joint development. Here, we propose a computational model of the development of active binocular vision to fill this gap. The model is based on a formulation of the active efficient coding theory, which proposes that eye movements as well as stimulus encoding are jointly adapted to maximize the overall coding efficiency. Under healthy conditions, the model self-calibrates to perform accurate vergence and accommodation eye movements. It exploits disparity cues to deduce the direction of defocus, which leads to coordinated vergence and accommodation responses. In a simulated anisometropic case, where the refraction power of the two eyes differs, an amblyopia-like state develops in which the foveal region of one eye is suppressed due to inputs from the other eye. After correcting for refractive errors, the model can only reach healthy performance levels if receptive fields are still plastic, in line with findings on a critical period for binocular vision development. Overall, our model offers a unifying conceptual framework for understanding the development of binocular vision. efficient coding | active perception | amblyopia | vergence | accommodation Author contributions: S.

Recurrent processing improves occluded object recognition and gives rise to perceptual hysteresis

“…A more complete model would include a vergence control mechanism that controls the plane of fixation autonomously. Self-calibrating models capable of doing so have been proposed in the active efficient coding framework ( Zhao et al, 2012 ; Eckmann et al, 2020 ). Another potential avenue for future research is to focus on the stereoscopic networks and analyze whether the individual filters become sensitive to certain disparities that might help to ignore occluders.…”

Unsupervised learning of haptic material properties

“…Receptive field properties in the early visual pathway ( Atick and Redlich, 1992 ; Olshausen and Field, 1996 ) as well as the tuning properties of auditory nerve fibers ( Lewicki, 2002 ; Smith and Lewicki, 2006 ) can emerge by efficiently encoding natural images or sounds, respectively. Recently, it was shown that efficient coding could also explain the simultaneous development of vergence and accommodation as a result of maximizing coding efficiency of the retinal signals ( Eckmann et al, 2020 ). There is currently a lot of interest whether higher-level representations can also be learned by efficient encoding of the retinal images ( Fleming and Storrs, 2019 ).…”

Binocular Integration of Perceptually Suppressed Visual Information in Amblyopia

“… 22 , 33 , 34 , 36 , 100 Although amblyopia is most successfully treated during childhood when cortical plasticity remains high, the visual system retains considerable plasticity even in adulthood. 105 – 107 Efforts to identify and remove the factors that limit plasticity in adults have been promising, using methods such as perceptual learning, 108 video games, 109 dichoptic treatments, 110 and noninvasive brain stimulation. 111 – 113 Ongoing research into the nature of interocular suppression in amblyopia will enable refinement of these potential treatment approaches.…”