# Rapid switching of vestibulo-motor pathways through voluntary eyelid closure in primates

## TL;DR

Voluntarily closing the eyes rapidly suppresses a reflex that stabilizes vision in primates, showing how the brain adapts movement control based on context.

## Contribution

The study reveals a conserved neural mechanism in primates where eyelid motor commands directly suppress the vestibulo-ocular reflex, independent of visual input.

## Key findings

- Voluntary eye closure causes a rapid and sustained reduction in vestibulo-ocular reflex (VOR) gains in primates.
- The suppression of VOR is linked to eyelid motor commands rather than the absence of visual input.
- Attempting to open restrained eyelids increases VOR gains, indicating motor commands influence vestibular processing.

## Abstract

Understanding how the brain adjusts movement control based on context is key to explaining adaptive behavior. The vestibulo-ocular reflex (VOR), with its well-defined circuitry, demonstrates adaptability—its primary role in stabilizing vision is suppressed when gaze redirection is required but remains resilient even in complete darkness. Here, we investigated VOR responses during intentional eye closure, when the need for visual stabilization is volitionally removed. Using scleral search coils, we measured human VOR responses and found a rapid ~36–90% reduction across movement directions when participants voluntarily closed their eyes, indicating a broad disruption of VOR pathways. This attenuation coincided with eyelid closure and persisted until the eyes reopened. Parallel experiments in monkeys confirmed these findings, ruling out mechanical factors and revealing a conserved neural mechanism across primates. Moreover, attempts to open restrained eyelids increased VOR gains, suggesting that motor commands for eye opening influence vestibular processing even without eyelid movement. These results demonstrate rapid, sustained VOR suppression linked to eyelid motor control, highlighting an energy-efficient neural strategy that dynamically adjusts sensory-motor processing when visual stabilization is certain to be unnecessary.

Voluntary eye closure rapidly suppresses the vestibulo-ocular reflex in primates, with suppression lasting until reopening. The effect stems from eyelid motor commands, not visual input, revealing context-dependent reflex gating.