Time perception is fluid and highly sensitive to visual input. Low-level features such as luminance, and temporal frequency can subtly stretch or compress perceived duration. At the same time, emotion, engagement, and cognitive load can bend time dramatically. Different neural mechanisms govern short versus long interval processing, meaning that time perception is not a single system but multiple interacting processes. Understanding these mechanisms allows designers to shape subjective duration intentionally. In head-mounted displays, for example, interventions that compress perceived time are used in VR immersion for medical treatment and professional training scenarios.