Distinct neural pathway and its information flow for blind individual's Braille reading

Area of Science:

• Neuroscience
• Cognitive Science
• Sensory Rehabilitation

Background:

• Braille reading in late blind individuals presents neural challenges.
• The specific brain networks and information flow for Braille reading are not well understood.

Purpose of the Study:

• To identify the neural pathway and information flow critical for Braille reading in late blind individuals.
• To explore the relationship between neural connectivity and Braille reading proficiency.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to examine brain activity during rest and Braille reading.
• Behavioral assessments with natural Braille texts were conducted.
• A multiple regression model was developed to predict reading proficiency.

Main Results:

• A unique left-lateralized resting-state connectivity between the lateral occipital cortex (LOC) and inferior frontal cortex (IFC) was observed in late blind individuals.
• This LOC-IFC connectivity strength correlated with Braille reading proficiency and increased with practice.
• During Braille reading, bidirectional information flow between LOC and IFC was enhanced, with dominant top-down modulation from IFC to LOC, predicting higher proficiency.

Conclusions:

• The occipito-frontal pathway, specifically the LOC-IFC link, plays a crucial role in natural Braille reading for the late blind.
• Both static connectivity and dynamic top-down cognitive strategies contribute to superior Braille reading performance.
• Findings offer insights for developing training programs for late blind individuals.