The acts of opening and closing the eyes are of importance for congenital blindness: Evidence from resting-state fMRI.
Neuroimage June 1, 2021 Yi-Xuan Feng, Ren-Yuan Li, Wei Wei et al.
Closing the eyes alters resting-state brain activity in both sighted and congenitally blind individuals, suggesting that the effect is inherent to human nature rather than learned from vision. The study compared 21 congenitally blind participants with 21 sighted controls using functional MRI. In both groups, eye closure increased low-frequency fluctuations in sensorimotor and occipital regions and decreased them in the medial prefrontal cortex. No differences appeared between blind participants with and without light perception. Between-group differences in the posterior insula and fusiform were attributed to experience (nurture). The authors contend that volitional eye closure focuses attention inward and is a natural human action, not dependent on visual experience.