Cortical Plasticity and Olfactory Function in Early Blindness.

Rodrigo Araneda,Isabel Cuevas,Philippe Rombaux,Laurent A Renier,Anne G De Volder

doi:10.3389/fnsys.2016.00075

Abstract

Over the last decade, functional brain imaging has provided insight to the maturation processes and has helped elucidate the pathophysiological mechanisms involved in brain plasticity in the absence of vision. In case of congenital blindness, drastic changes occur within the deafferented “visual” cortex that starts receiving and processing non visual inputs, including olfactory stimuli. This functional reorganization of the occipital cortex gives rise to compensatory perceptual and cognitive mechanisms that help blind persons achieve perceptual tasks, leading to superior olfactory abilities in these subjects. This view receives support from psychophysical testing, volumetric measurements and functional brain imaging studies in humans, which are presented here.

Highlights

Cortical Plasticity and Olfactory Function in Early BlindnessIn case of congenital blindness, drastic changes occur within the deafferented “visual” cortex that starts receiving and processing non visual inputs, including olfactory stimuli
The plasticity of the human brain, that is, its ability to adapt to environmental constraints by creating changes in its connectivity and/or in the neurons themselves, is one of its most outstanding properties (Rakic, 2002)
The emergence of behavioral adjustments in early blindness has been usually associated with the functional reorganization of the deafferented visual cortical areas, which are recruited to process non-visual information (Amedi et al, 2003; Gougoux et al, 2005; Ricciardi et al, 2007; Kupers et al, 2010; Renier et al, 2010; Collignon et al, 2011; Kitada et al, 2014; Bedny et al, 2015; Dormal et al, 2016)

Summary

Cortical Plasticity and Olfactory Function in Early Blindness

In case of congenital blindness, drastic changes occur within the deafferented “visual” cortex that starts receiving and processing non visual inputs, including olfactory stimuli. This functional reorganization of the occipital cortex gives rise to compensatory perceptual and cognitive mechanisms that help blind persons achieve perceptual tasks, leading to superior olfactory abilities in these subjects.

INTRODUCTION

Odor categorization

Findings

FUNCTIONAL NEUROIMAGING OF ODOR PROCESSING IN BLIND HUMANS