Daphné Silvestre (PhD student)
Aging in Vision and Action Lab
CNRS – INSERM – University Pierre&Marie Curie
17, rue Moreau F-75012 Paris, France
Healthy aging alters all processing levels of the visual system, such as optics of the eye, retinal processing, early pre-attentive processing, and high-level attention-based processing. These alterations affect many visual functions such as visual acuity, contrast sensitivity, motion perception and visual attention. This project aims at characterizing the age-related sensitivity losses on various visual functions and identifying the underlying functional and neurobiological alterations responsible for these perceptual losses. We will address this issue by extensively using the external noise paradigm, which enables the factorization of the sensitivity into internal equivalent noise and calculation efficiency, and by combining experimental psychophysics with computational modeling. The effect of aging will be characterized in various tasks (e.g., contrast sensitivity, motion perception) and the underlying factors affected by aging will be psychophysically investigated (e.g., to determine whether the effect of aging on a particular function is due to an increase in internal noise or a decrease in processing efficiency). These empirical data will be used to develop computational models and to test which neurobiological alterations could be responsible for the observed visual function losses.
Keywords: vision psychophysics, visual aging, contrast sensitivity, motion sensitivity, neural noise.
CV (pdf): [ download ]
- Healthy aging impairs photon absorption efficiency of cones. Invest. Ophthalmol. Vis. Sci., (in press). (2019)
- Considerable age-related contrast sensitivity loss due to less efficient cones. In ARVO Annual Meeting 2019, Vancouver, Canada. (2019)
- Absorption efficiency of cones is considerably affected with heathy aging. In ECVP. (2018)
- Internal noise sources limiting contrast sensitivity. Scientific Reports, 8(1):2596. (2018)
- Adding temporally localized noise can enhance the contribution of target knowledge on contrast detection. Journal of Vision, 17:1-10. (2017)
- Spatiotemporal maps of quantal noise, dark light and late neural noise limiting contrast sensitivity. In Vision Sciences Society. (2017)
- Contrast sensitivity: Measuring late internal noise across spatial frequencies. In Vision Sciences Society meeting, St. Pete Beach, Florida, USA. (2016)