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Short segments of two TV programs without audio description (AD) were presented to 25 subjects with low vision and 24 subjects with normal vision, and 29 additional subjects heard only the standard audio portions. The subjects then answered questions based on the visual information contained in the AD of the programs. The subjects with normal vision performed the best, followed by those with low vision and those who heard only the audio portion; all performed at better than chance levels. The results indicate that although AD may provide information on visual details to visually impaired audiences, some of the information in the AD may be obtained from the standard audio portion.

13 págs.; 5 figs. ; © 2015 ARVO. The ability of the visual system to compensate for differences in blur orientation between eyes is not well understood. We measured the orientation of the internal blur code in both eyes of the same subject monocularly by presenting pairs of images blurred with real ocular point spread functions (PSFs) of similar blur magnitude but varying in orientations. Subjects assigned a level of confidence to their selection of the best perceived image in each pair. Using a classification-images–inspired paradigm and applying a reverse correlation technique, a classification map was obtained from the weighted averages of the PSFs, representing the internal blur code. Positive and negative neural PSFs were obtained from the classification map, representing the neural blur for best and worse perceived blur, respectively. The neural PSF was found to be highly correlated in both eyes, even for eyes with different ocular PSF orientations (rPos = 0.95; rNeg = 0.99; p < 0.001). We found that in subjects with similar and with different ocular PSF orientations between eyes, the orientation of the positive neural PSF was closer to the orientation of the ocular PSF of the eye with the better optical quality (average difference was ∼10°), while the orientation of the positive and negative neural PSFs tended to be orthogonal. These results suggest a single internal code for blur with orientation driven by the orientation of the optical blur of the eye with better optical quality. ; The authors acknowledge the funding received from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007- 2013) / ERC Grant Agreement n8 294099 (SM), Spanish Government grant FIS2011-264605 (SM), the 7th Framework Programme of the European Community through the Marie Curie Initial Training Network OpAL (OpAL is an Initial Training Network funded by the European Commission under the Seventh Framework Programme (PITN-GA-2010- 264605, AR) and USA NIH grant R01EY05957 (EP). ; Peer Reviewed

Background:The image formed by the eye's optics is blurred by the ocular aberrations, specific to each eye. Recent studies demonstrated that the eye is adapted to the level of blur produced by the high order aberrations (HOA). We examined whether visual coding is also adapted to the orientation of the natural HOA of the eye.Methods and Findings:Judgments of perceived blur were measured in 5 subjects in a psychophysical procedure inspired by the >Classification Images> technique. Subjects were presented 500 pairs of images, artificially blurred with HOA from 100 real eyes (i.e. different orientations), with total blur level adjusted to match the subject's natural blur. Subjects selected the image that appeared best focused in each random pair, in a 6-choice ranked response. Images were presented through Adaptive Optics correction of the subject's aberrations. The images selected as best focused were identified as positive, the other as negative responses. The highest classified positive responses correlated more with the subject's Point Spread Function, PSF, (r = 0.47 on average) than the negative (r = 0.34) and the difference was significant for all subjects (p<0.02). Using the orientation of the best fitting ellipse of angularly averaged integrated PSF intensities (weighted by the subject's responses) we found that in 4 subjects the positive PSF response was close to the subject's natural PSF orientation (within 21 degrees on average) whereas the negative PSF response was almost perpendicularly oriented to the natural PSF (at 76 degrees on average).Conclusions:The Classification-Images inspired method is very powerful in identifying the internally coded blur of subjects. The consistent bias of the Positive PSFs towards the natural PSF in most subjects indicates that the internal code of blur appears rather specific to each subject's high order aberrations and reveals that the calibration mechanisms for normalizing blur also operate using orientation cues. © 2013 Sawides et al. ; The authors acknoweldge funding from Spanish Government grant FIS2011-25637 (to SM), European Research Council Advanced Grant ERC-AdG- 294099 (to SM), and US National Institutes of Health EY05957 (to EP). ; Peer Reviewed

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018 ; Support European Research Council ERC-2011-AdG-294099; Spanish Government FIS2014 ; Peer reviewed