Gordon’s earlier work had a major focus on the mechanisms for coding contrast in the visual pathway. The paper by Legge & Foley (1980) has more than 1000 citations as a foundational psychophysical study on this topic. In a more recent study, Kwon et al. (2009) used both psychophysical and fMRI measurements to show how contrast coding changes (adapts) following only four hours of visual contrast deprivation.
Gordon’s interest in contrast coding has also had a major impact on his low-vision research. In a 2016 paper with Susana Chung, we showed how the shape of contrast-sensitivity functions (CSFs) in low vision relate to CSFs in normal vision. We have also shown how reduced contrast sensitivity is related to reduced acuity in different forms of eye disease (Xiong et al., 2020), and the impact of reduced contrast sensitivity in low vision on reading performance (Rubin & Legge, 1989)
Gordon has also had a long-time interest in binocular vision. He showed how the two eyes combine contrast signals from the two eyes in binocular contrast summation (Legge, 1984) and stereopsis (Legge & Gu, 1989).
Chung, S.T.L. & Legge G.E. (2016). Comparing the shape of contrast sensitivity functions for normal and low vision. Investigative Ophthalmology & Visual Science, 57 (1), 198-207. (article) (PDF)
Kwon, M., Legge, G.E., Fang, F., Cheong, A.M.Y. & He, S. (2009). Adaptive changes in visual cortex following prolonged contrast reduction. Journal of Vision, 9(2), 20. (article) (PDF)
Legge, G.E. (1984). Binocular contrast summation. I. Detection and discrimination. Vision Research, 24(4), 373-383. (article) (PDF)
Legge, G.E. (1984). Binocular contrast summation. II. Quadratic summation. Vision Research, 24(4), 385-394. (article) (PDF)
Legge, G.E. & Foley, J.M. (1980). Contrast masking in human vision. Journal of the Optical Society of America, 70(12), 1458-1471. (article) (PDF)
Legge, G.E. & Gu, Y. (1989). Stereopsis and contrast. Vision Research, 29(8), 989-1004. (article) (PDF)
Rubin, G.S. & Legge, G.E. (1989). Psychophysics of reading. VI. The role of contrast in low vision. Vision Research, 29(1), 79-91. (abstract) (PDF)
Xiong, Y.-Z., Kwon, M., Bittner, A.K., Virgili, G., Giacomelli, G. & Legge, G.E. (2020). Relationship between acuity and contrast sensitivity: Differences due to eye disease. Investigative Ophthalmology and Visual Science.61(6), 40. (article) (PDF)