The vestibular system is responsible for balance and spatial orientation, which relies on gravity to interpret “up,” “down,” and motion. In microgravity, this reference is essentially lost, leading to adaptive changes in how the brain processes vestibular input. When astronauts return to Earth, their vestibular system is temporarily mismatched with gravity again, resulting in impaired balance and spatial disorientation, especially evident when visual cues are removed (e.g., eyes closed). This ha