https://journalofillusion.net/index.php/joi <p>Focusing, on perceptual illusions, cognitive illusions (e.g. magic or misunderstanding) or physical illusions (e.g. mirage or the Doppler effect), <strong>JOI is now open for submissions!</strong> Article categories include: Phenomenal reports, Review reports, Registered reports and Post-publication commentaries. Learn more about the Aims and Scope, Review criteria and article categories <strong><a href="https://journalofillusion.net/index.php/joi/about">here</a></strong>.</p> Ritsumeikan University en-US Journal of Illusion 2436-4045 <p>Authors retain copyright of their work, with first publication rights granted to Journal of Illusion.</p> https://journalofillusion.net/index.php/joi/article/view/11219 <p>We present a new illusion that challenges our understanding of stereo vision. The illusion consists of a larger circle at 50 cm, and smaller circle in front of it at 40 cm, with constant angular sizes throughout. We move the larger circle forward by 10 cm (to 40 cm) and then back again (to 50 cm). The question is, what distance should we move the smaller circle forward and backward to maintain a constant perceived separation in depth between the circles? Constant physical distance (10 cm) or constant retinal disparity (6.7 cm)? Observers choose constant retinal disparity. The ‘Linton Stereo Illusion’ therefore appears to suggest that perceived stereo depth reflects retinal disparities rather than 3D geometry.</p> Paul Linton Copyright (c) 2026 Paul Linton https://creativecommons.org/licenses/by-nc-nd/4.0 2026-07-01 2026-07-01 6 10.47691/joi.v6.11219 https://journalofillusion.net/index.php/joi/article/view/13041 <p>Some special images are known to produce a learning effect in 3D perception. This image represents a 3D scene but it has been degraded so that the 3D information of the scene can be perceived from the image only after the learning has taken place. This study presents a new type of image that is not degraded but can produce a learning effect in 3D perception. This image has a luminance gradient of shading that represents a saddle (hyperbolic) shape that is perceived on the basis of the gradient only after the saddle shape has been learnt on the basis of binocular disparity. This learning effect suggests that the 3D information can be transferred across depth cues in the visual system.</p> Tadamasa Sawada Hirohiko Kaneko Copyright (c) 2026 The Authors https://creativecommons.org/licenses/by-nc-nd/4.0 2026-06-26 2026-06-26 6 10.47691/joi.v6.13041