Severe distortion in the representation of foveal visual image locations in short-term memory

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 119; no. 24; pp. 1 - 9
• Main Authors: Willeke, Konstantin F., Cardenas, Araceli R., Bellet, Joachim, Hafed, Ziad M.
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 14.06.2022
• Subjects: Acuity; Biological Sciences; Distortion; Fovea Centralis - physiology; Humans; Localization; Memory, Short-Term; Mental Recall; Short term memory; Visual Perception; Visual system; oblique effect; diagonal bias; short-term memory; foveal bias; microsaccades
• ISSN: 0027-8424; 1091-6490; 1091-6490
• DOI: 10.1073/pnas.2121860119

The foveal visual image region provides the human visual system with the highest acuity. However, it is unclear whether such a high fidelity representational advantage is maintained when foveal image locations are committed to short-term memory. Here, we describe a paradoxically large distortion in foveal target location recall by humans. We briefly presented small, but high contrast, points of light at eccentricities ranging from 0.1 to 12°, while subjects maintained their line of sight on a stable target. After a brief memory period, the subjects indicated the remembered target locations via computer controlled cursors. The biggest localization errors, in terms of both directional deviations and amplitude percentage overshoots or undershoots, occurred for the most foveal targets, and such distortions were still present, albeit with qualitatively different patterns, when subjects shifted their gaze to indicate the remembered target locations. Foveal visual images are severely distorted in short-term memory.