Brain Plasticity in Blind Subjects Centralizes Beyond the Modal Cortices

Area of Science:

• Neuroscience
• Cognitive Science
• Neuroimaging

Background:

• The human brain exhibits plasticity following sensory deprivation.
• In blindness, visual cortex regions are activated by non-visual stimuli, but underlying mechanisms are unclear.
• Research has primarily focused on unimodal visual regions, neglecting multimodal and heteromodal cortices.

Purpose of the Study:

• To investigate neuroplastic alterations in brain networks beyond visual cortices in blind individuals.
• To explore functional reorganization in regional and distributed neural systems using graph-theory based analyses.
• To compare cross-modal plasticity in late-onset blind (LB) and congenitally blind (CB) individuals.

Main Methods:

• Applied interconnector analyses and local/distant connectivity graph-theory approaches.
• Analyzed functional reorganization in LB and CB cohorts against sighted controls.
• Measured functional network alterations using the degree of differential links (DDL).

Main Results:

• Functional network alterations were observed in sensory cortices.
• Neuroplastic changes were most prominent in multimodal and association cortices.
• LB individuals showed enhanced connections in parieto-opercular, temporoparietal junction (TPJ), and ventral premotor (vPM) regions.
• CB individuals exhibited increased superior parietal cortex (SPC) connections.

Conclusions:

• Recipient multi-sensory integration areas play a critical role in network reorganization and cross-modal plasticity in blindness.
• Cross-modal neuroplasticity and adaptive sensory-motor/auditory functions may involve reorganization within multimodal integration regions.
• Findings reveal significant brain network reorganization beyond visual unimodal areas in blind populations.