Language Processing in Blind Early Visual Cortex? Understanding Limits of Functional Plasticity in Human Brain

What makes the cognitive functions to always fall in the same brain niches, in people all around the world? This consistency might be driven by shared experience, characteristic of our species.

Alternatively, it might be driven by genetic blueprints, predisposing certain brain areas to process specific types of information.To tackle this puzzle, I want to understand the functional plasticity of the early visual cortex, genetically predisposed to process vision, in people born blind. We know that, in blind individuals, this brain region responds to language.

While this discovery can be groundbreaking for our theories of brain plasticity, its theoretical implications are debated, particularly because we do not know what properties of linguistic stimuli are represented in the blind early visual cortex.The project objective is to fill this gap in knowledge and disentangle two hypotheses for language processing in the early visual cortex of blind individuals.

One hypothesis is that linguistic effects in this region are an extension of its typical visuospatial computations.

That implies that this region represents linguistic stimuli through concrete, physical properties of language referents.

An alternative possibility is that responses to language in the blind early visual cortex are driven by the development of truly abstract representation in this region.

That implies that this region can represent more conceptual properties of language referents or even the linguistic properties of words and expressions themselves.

My project will use advanced neuroimaging approaches, such as “mind reading” from fMRI signals and inducing “virtual lesions” with TMS, to thoroughly test these two hypotheses.

By doing so, it will evaluate two fundamentally different perspectives on functional plasticity in the human brain, and will significantly improve our understanding of how sensory experience and genetic blueprints shape the implementation of cognitive functions in this organ.