In 1804, Troxler discovered that, when an observer fixates on a point in central vision and attends to a peripheral stationary stimulus, the peripheral stimulus eventually fades from awareness. This phenomenon is known as Troxler's effect and is allegedly influenced by spatial attention. Asymmetries in Troxler's effect along horizontal and vertical meridian were a recent discovery. However, viewer-and environment-centered reference frames were aligned in prior studies, making it impossible to assess whether asymmetries correspond to viewer-versus environment-centered coordinate systems. This study was undertaken to (a) replicate the asymmetries in the upright condition among 39 participants without health issues and (b) use the asymmetries to test contrasting predictions made by viewer-and environment-centered coordinate systems when they are decoupled using an experimental head-tilt condition. The horizontal and vertical asymmetries were replicated and consistent with a viewer-centered rather than an environment-centered reference frame.