{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,10]],"date-time":"2026-11-10T16:43:17Z","timestamp":1794328997637,"version":"4.9.0"},"reference-count":27,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,19]],"date-time":"2025-12-19T00:00:00Z","timestamp":1766102400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Objectives: To evaluate the feasibility and efficacy of a brief, scaffolded virtual reality (VR)-based perceptual-learning protocol to improve stereovision in adults without measurable baseline global stereopsis. Methods: Prospective interventional pilot study with a normal-vision reference group. Fourteen adults were enrolled; nine with nil global stereoacuity formed the intervention group and five with normal binocular vision served as controls. Intervention participants completed 8\u201310 VR sessions (~30 min each over two weeks) using a disparity-driven depth-matching task with individualized thresholds, virtual prism compensation, and interocular contrast balancing. Primary outcomes were changes in clinical stereoacuity (local and global) and Binocular Function (BF). Secondary outcomes included positive fusional vergence (PFV), binocular imbalance (inter-ocular contrast ratio), and in-game depth discrimination error (arcseconds). Results: Global stereoacuity improved with four of nine participants who initially showed no measurable global stereopsis achieving measurable thresholds after training (post: 861.11 \u00b1 537.08 arcsec, IQR = 800.00; p = 0.06). Local stereoacuity improved near (pre: 616.67 \u00b1 532.68 arcsec, IQR = 1100.00; post: 361.67 \u00b1 537.11, IQR = 200.00; p = 0.03) and at a distance (pre: 715.11 \u00b1 573.54 arcsec, IQR = 1114.00; post: 437.11 \u00b1 510.41, IQR = 405.00; p = 0.03). BF score improved from 4.33 \u00b1 0.50 (IQR = 1.00) to 3.51 \u00b1 1.14 (IQR = 1.30) (p = 0.03). PFV break at distance increased (pre: 17.83 \u00b1 17.53\u0394, IQR = 23.50; post: 24.50 \u00b1 17.12\u0394, IQR = 28.50; p = 0.04), and the binocular imbalance showed a nonsignificant trend towards improvement (p = 0.09). In-game depth error decreased from 752.11 \u00b1 384.50 arcsec (IQR = 553.00) to 221.78 \u00b1 79.12 (IQR = 105.00) (p &lt; 0.01). Control participants achieved a mean depth error of 43.00 \u00b1 10.30 arcsec after three sessions. Conclusions: A short-dose, individualized VR protocol yielded gains in stereoacuity and binocular function in adults with severe stereodeficiency, with transfer from in-game learning to standard clinical measures. While the sample size was limited, the approach proved feasible and was well tolerated, showing encouraging efficiency versus prior high-dose regimens.<\/jats:p>","DOI":"10.3390\/jcm15010006","type":"journal-article","created":{"date-parts":[[2025,12,19]],"date-time":"2025-12-19T11:03:46Z","timestamp":1766142226000},"page":"6","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Effects of Perceptual Learning Through Binocular Virtual Reality Exercises on Low Stereopsis"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3683-9644","authenticated-orcid":false,"given":"Mar\u00eda Teresa","family":"Calder\u00f3n-Gonz\u00e1lez","sequence":"first","affiliation":[{"name":"Servicio de Oftalmolog\u00eda, Hospital Vital \u00c1lvarez Buylla, 33611 Mieres, Spain"},{"name":"Departamento de \u00d3ptica, Facultad de Ciencias, Universidad de Granada, 18071 Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5970-4841","authenticated-orcid":false,"given":"Irene","family":"S\u00e1nchez-Pav\u00f3n","sequence":"additional","affiliation":[{"name":"Departamento de F\u00edsica Te\u00f3rica, At\u00f3mica y \u00d3ptica, Universidad de Valladolid, 47005 Valladolid, Spain"},{"name":"Instituto Universitario de Oftalmobiolog\u00eda Aplicada (IOBA), Universidad de Valladolid, 47005 Valladolid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6793-667X","authenticated-orcid":false,"given":"Juan A.","family":"Portela-Camino","sequence":"additional","affiliation":[{"name":"Department of Optometry, Begira Ophthalmologic Clinic, 48001 Bilbao, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5912-1400","authenticated-orcid":false,"given":"Santiago","family":"Mart\u00edn-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Department of Construction and Manufacturing Engineering, University of Oviedo, 33204 Gijon, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Wade, N.J., and Swanston, M. 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