Selected Conference Presentations (Posters and Talks)
Wu, Q., Brielmann, A. A., Simoncelli, M. S., Pelli, D. G. (2018) The dimensionality of beauty. Journal of Vision 2018;18(10):1326. doi: 10.1167/18.10.1326. https://jov.arvojournals.org/article.aspx?articleid=2700306&resultClick=1 Brielmann, A. A., and Pelli, D. G. (2017). Pleasure integration. Poster at the European Conference on Visual Perception, August 27 – 31, 2017 in Berlin, Germany. doi: 10.7490/f1000research.1115186.1 https://f1000research.com/posters/7-10 Pelli, D. G., & Giglio, A. (2017) What internal noise source limits peripheral vision? European Conference on Visual Perception, August 27 – 31, 2017 in Berlin, Germany. (poster) doi: 10.7490/f1000research.1115200.1 https://f1000research.com/posters/7-28 Pelli, D. G., & Yiltiz, H. (2017) What internal noise source limits peripheral vision? Vision Sciences Society, May 19 – 24, 2017, in St. Pete Beach, Florida. Brielmann, A. A., & Pelli, D. G. (2017). Toward a quantitative model of feeling beauty. Vision Sciences Society, May 19 – 24, 2017, in St. Pete Beach, Florida. Yiltiz, H., & Pelli, D. G. (2017) Noise masking and crowding reveal two very different kinds of spatial integration. Vision Sciences Society, May 19 – 24, 2017, in St. Pete Beach, Florida. (poster) doi: 10.7490/f1000research.1115201.1 https://f1000research.com/posters/7-31 Waugh, S. J., Formankiewicz, M. A., & Pelli, D. G. (2017) Cross-optotype metrics for foveal lateral masking. Vision Sciences Society, May 19 – 24, 2017, in St. Pete Beach, Florida. Brielmann, A. A. & Pelli, D. G. (2016) Nobody likes a fake: Aesthetic value depends on perceived authenticity. European Conference on Visual Perception, Barcelona, Spain, August 31, 2016.
https://aennebrielmann.wordpress.com/publications
https://denispelli.com/posters.htmlYiltiz, H., Wu, X. Y., & Pelli, D. G. (2016) Crowding area sets a lower bound on the neural noise that limits letter identi cation. 16th Annual Meeting of the Vision Sciences Society, May 13-18, 2016 in St. Pete Beach, Florida.
https://denispelli.com/posters.htmlVale, L. & Pelli, D. G. (2016) The role of exposure duration in the experience of beauty. Annual Meeting of the Vision Sciences Society, St. Pete Beach, Florida, May 13-18, 2016.
https://denispelli.com/posters.htmlBrielmann, A. A. & Pelli, D. G. (2016) Beauty requires thought: The experience of beauty is selectively impaired by a demanding cognitive task. Annual Meeting of the Vision Sciences Society, St. Pete Beach, Florida, May 13-18, 2016.
https://denispelli.com/posters.html
https://aennebrielmann.wordpress.com/publicationsBrielmann A., & Pelli, D. G. (2016) Beauty requires thought: The experience of beauty is selectively impaired by a cognitive task. 23rd Annual Meeting of the
Cognitive Neuroscience Society, New York City, New York, April 2-5, 2016.
https://denispelli.com/posters.html https://aennebrielmann.wordpress.com/publicationsPelli, D. G., and Raghavan, M. (2016) Photon and cortical noises limit what we see. Computational and Systems Neuroscience (Cosyne) 2016, February 25 - 28, 2016 in Salt Lake City. (poster) doi: 10.7490/f1000research.1115203.1
https://f1000research.com/posters/7-33
AbstractPowerpoint (13 MB) Pelli, D. G. (2015) Converging on a computational model of object recognition: psychophysics & machine learning. Applied Vision Association (AVA). Queen Mary University of London, London, December 21, 2015.
http://theava.net/meetings/qmul2015.htmlAltholz, J., & Blauch, N. (2015) Using noise to study letter identification: Evidence for four types of spatial interaction. NYU Diversity Conference. New York City. July 17, 2015. Pelli, D. G., & Rosen, S. (2015) Supposing that crowding is compulsory grouping suggests a remarkably simple model for object recognition. Vision Sciences Society, St. Pete Beach, Florida, May 15-20, 2015, 53.4109. Vale, L., Gerger, G., Leder, H., & Pelli, D. G. (2015) Correlating beauty and two measures of pleasure. Vision Sciences Society, St. Pete Beach, Florida, May 15-20, 2015, 26.3045. VIDEO (33 min) Pelli, D. G. (2014) Legibility: How we see letters. WebFontDay, Munich, November 8, 2014.
Program.
NEWS: Dohmann, A. (2014) Das War der (Web) Font Day. PAGE 10.11.2014POWERPOINT (65 MB) Gleich, J. and Pelli, D.G. (2014) Is popular dance beautiful? A method to assess pleasure in dance. PoP Moves, Royal Holloway, University of London, October 18, 2014. http://popmoves.com/archive/october-2014-conference/ Pelli, D. G. and Vale, L. (2014) Lingering pleasure in the experience of beauty. International Association for Empirical Aesthetics, New York, New York, August 22-24, 2014. Vale, L., and Pelli, D. G. (2014) The duration of pleasure in the experience of beauty. Vision Sciences Society, St. Pete Beach, Florida, May 16-21, 2014, 63.328. http://f1000.com/posters/browse/summary/1095735 Ziskind, A.J., Hénaff, O., LeCun, Y., & Pelli, D.G. (2014) The bottleneck in human letter recognition: A computational model. Vision Sciences Society, St. Pete Beach, Florida, May 16-21, 2014, 56.583. http://f1000.com/posters/browse/summary/1095738 A.J. Ziskind, Y. LeCun, D.G. Pelli (2014) Two machine-learning models of object recognition exhibit key features of human performance. Moore-Sloan Data Science Initiative Launch Event, NYU, New York, April 28, 2014. http://cds.nyu.edu/projects/two-machine-learning-models-object-recognition-exhibit-key-features-human-performance/ S. Rosen & D. G. Pelli (2012) Reading faster by reducing visual crowding. Vision Sciences Society Annual Meeting 2012, May 10-15, 2012, 34.12
http://f1000.com/posters/browse/summary/1090326Pelli, D. G., Barlow, M. T., & Barlow, H. B. (2012) The cortical demands of two kinds of perceptual task. Journal of Vision, 2012, 12 (9), p. 275.
http://www.journalofvision.org/content/12/9/275.abstractD. G. Pelli, S. Song, D. M. Levi (2011) Improving the screening of children for amblyopia. Vision Sciences Society, Naples, Florida, May 6-11, 2011. Jacob, M., Rosen, S., & Pelli, D. G. (2011) The way we see it: How familiarity affects perception. NYU Undergraduate Research Conference. New York City, April 15, 2011. Schnebelen, W., Tillman, K. A., Dubois, M., & Pelli, D. G. (2011) As children learn to read, eye and ear improve but always integrate well. NYU Undergraduate Research Conference. New York City, April 15, 2011. Pelli, D. G., Freeman, J., and Chakravarthi, R. (2010). Crowding combines. Vision Sciences Society. Naples, Florida. May 7-12, 2010. ABSTRACT. Visual crowding provides a window into object recognition: observers fail to recognize objects in clutter. Here we ask, what do they see instead? We analyze observers’ errors to show that crowding necessarily reflects the combination of information across multiple complex objects, rather than the mislocalization (or substitution) of one object for another. First, we presented single letters, randomly chosen, in noise in the periphery and tabulated a confusion matrix based on observers’ (n=3) reports. We then tested the same observers in a classic crowding task, in which they viewed a triplet (target and two flankers) of closely spaced letters in the periphery (10 deg) and reported the identity of the middle target. For each observer, we tailored the triplets based on that observer’s single-letter confusion matrix. One flanker was chosen to be a letter that was most confused with (most “similar” to) to the target, and the other was chosen to be a letter that was least confused (least similar). Consistent with the literature, when mistaken, observers tend to report the flankers. The crucial issue, however, is which of the two flankers observers report on these trials. Blind substitu- tion predicts that the two flankers (similar and dissimilar) are equally likely to be reported. Instead, we find that observers are more likely to report the similar flanker (70%) than the dissimilar flanker (30%). The effect of similar- ity on erroneous responses proves that the response combines information from both the target and the reported flanker. By systematically tailoring the stimuli, we induced a bias in the reports that reveals a pooled, “mon- grel-like,” underlying percept. Our method, applicable to any object, gen- eralizes the evidence for “compulsory pooling” from the narrow domain of grating orientation (Parkes et al., 2001) to complex, everyday objects.
View the one-hour video at:
http:futureofreading.cias.rit.edu/2010/video.php@DennisPelli
Pelli, D.G. (2010) The role of vision in reading. One-hour talk at the "Future of Reading 2010 Symposium" at Rochester Institute of Technology. Program of Symposium
ABSTRACT. We’ve all been read to as children. And blind people learn to read braille. But, mostly, reading is a visual act. The advance of printing and display technology continues unabated, with large social consequences, especially near-universal literacy. And now, as Cody Brown says, publishing is the new literacy. Still, we all read through human eyes, by optically imaging text onto our retinas. We read by recognizing a serial stream of words. Each word is an object. The limitations of object recognition limit reading. The two most important limitations are letter size and spacing (center to center). Those two factors limit reading speed and describe most of the variation in reading by normal and clinical populations. Visual object recognition will constrain reading for the foreseeable future.
Rosen, S., Chakravarthi, R., and Pelli, D. G. (2010). Pool party: Objects rule! Vision Sciences Society. Naples, Florida. May 7-12, 2010.
Granata, Y., Chakravarthi, R., Rosen, S., and Pelli, D. G. (2010). Size pooling. Vision Sciences Society. Naples, Florida. May 7-12, 2010.
Raghavan, M., Remler, B. F., Rozman, S., & Pelli, D. G. (2010). Patients with visual "snow" have normal equivalent input noise levels. Investigative Ophthalmology & Visual Science, 51, ARVO E-Abstract 1808/D1660. (poster) doi: 10.7490/f1000research.1115207.1
https://f1000research.com/posters/7-36
ABSTRACTPelli, D. G. (2009). Towards an easier way to measure the visual span. [Abstract]. Journal of Vision, 9(8): 1002, http://journalofvision.org/ [Vision Sciences Society, Naples, Florida, May 9-14, 2009] Tillman, K. A., & Pelli, D. G. (2009). Reading pictures. [Abstract]. Journal of Vision, 9(8): 803
http://journalofvision.org/ [Vision Sciences Society, Naples, Florida, May 9-14, 2009]Rosen, S. (2009). A new technique for measuring the critical spacing of crowding. [Abstract]. Journal of Vision, 9(8): 998, http://journalofvision.org/ [Vision Sciences Society, Naples, Florida, May 9-14, 2009] Chakravarthi, R., Tillman, K. A., & Pelli, D. G. (2009). Features used or features available? [Abstract]. Journal of Vision, 9(8): 789 Rosen, S., Chakravarthi, R., Pelli, D. G. (2008). Nasotemporal asymmetry of acuity and crowding. Journal of Vision 8(6):972. doi: 10.1167/8.6.972. Abstract Tillman, K. A., Araki, M., & Pelli, D. G. (2008). Crowding shows that faces have parts and bodies do not. Perception 37 ECVP Abstract Supplement, page 33.
http://www.perceptionweb.com/abstract.cgi?id=v080115Cantone, A. R., Tillman, K. A., & Pelli, D. G. (2008). Eccentric features integrate slowly [Abstract]. Journal of Vision, 8(6):653, http://journalofvision.org/8/6/653/ Suchow, J. W., & Pelli, D. G. (2008). Letter learning: Feature detection and integration [Abstract]. Journal of Vision, 8(6):1133, http://journalofvision.org/8/6/1133/ Powerpoint Kleiner, M., Brainard, D., Pelli, D., Ingling, A., Murray, R., & Broussard, C. (2007). What’s new in Psychtoolbox-3. Perception, 36(14), 1. Cited by 651.
Pelli, D., Song, S., & Levi, D. (2007). Amblyopic reading is crowded. [Abstract]. Journal of Vision, 7(9):519, http://journalofvision.org/7/9/519/, doi:10.1167/7.9.519. [Vision Sciences Society, Sarasota, Florida, May 2007] Published as Levi, Song, and Pelli (2007).
S. Song, D. M. Levi, and D. G. Pelli (2007) Can “equivalent eccentricity” account for amblyopic vision? Association for Research in Vision and Ophthalmology. [Abstract] Baron, J., & Pelli, D. G. (2006). Crowding counting. [Abstract]. Journal of Vision, 6(6):198.
http://journalofvision.org/6/6/198 [Vision Sciences Society, Sarasota, Florida, May 2006]
Bergman, C., Martelli, M., Burani, C., Pelli, D. G., & Zoccolotti, P. (2006). How the word length effect develops with age. [Abstract]. Journal of Vision, 6(6):999. http://journalofvision.org/6/6/999 [Vision Sciences Society, Sarasota, Florida, May 2006] Pelli, D. G., & Tillman, K. A. (2006). Crowding limits reading. [Abstract]. Journal of Vision, 6(6):993, http://journalofvision.org/6/6/993/, doi:10.1167/6.6.993. [Vision Sciences Society, Sarasota, Florida, May 2006] Published as Pelli, Tillman, Freeman, Su, Berger, & Majaj (2007). Tillman, K. A., Pelli, D. G., Martelli, M., Stott, J., & Rosenblatt, J. (2006). Is reading serial? [Abstract]. Journal of Vision, 6(6):995, http://journalofvision.org/6/6/995/, doi:10.1167/6.6.995. [Vision Sciences Society, Sarasota, Florida, May 2006] Oruç, I., Landy, M. S., & Pelli, D. G. (2005). Noise masking reveals channels for second-order letters. [Abstract]. Journal of Vision, 5(8): 183, http://journalofvision.org/5/8/183. [Vision Sciences Society, Sarasota, Florida, May 2005]
Published as Oruç, I., Landy, M. S., & Pelli, D. G. (2006) Noise masking reveals channels for second-order letters. Vision Research, 46, 1493–1506. [PubMed]
Pelli, D. G., Su, M., Berger, T.D., Majaj, N.J., Martelli, M., Guo, S., & Tillman, K. (2005). Crowding, shuffling, and capitalizing reveal three processes in reading. [Abstract]. Journal of Vision, 5(8):806, http://journalofvision.org/5/8/806. [Vision Sciences Society, Sarasota, Florida, May 2005] Published as Pelli & Tillman (2007). Suchow, J. W., & Pelli, D. G. (2005). Learning to identify letters: Generalization in high-level perceptual learning. [Abstract]. Journal of Vision, 5(8):712, http://journalofvision.org/5/8/712. [Vision Sciences Society, Sarasota, Florida, May 2005] Pelli, D. G., Martelli, M., and Majaj, N. J. (2004) Using crowding to determine whether an object is identified as a whole or by parts [Abstract]. Journal of Vision, 4(8):507, http://journalofvision.org/4/8/507. [Vision Sciences Society, Sarasota, Florida, May 2004] James, K. H., Martelli, M., James, T. W., Majaj, N. J., Pelli, D. G., and Gauthier, I. (2004) fMRI reveals the role of the left anterior fusiform gyrus in letter detection [Abstract]. Journal of Vision, 4(8):512, http://journalofvision.org/4/8/512. [Vision Sciences Society, Sarasota, Florida, May 2004] Steingrimsson, R., Majaj, N. J., & Pelli, D. G. (2003) Where are letters processed and learned? Neural specialization for letter processing under different learning conditions. Perception 32 supplement. Steingrimsson, R., Gilman, J., Ramos, E., Majaj, N. J., & Pelli, D. G. (2003) Where are letters learned? An fMRI study. NYU Natural Sciences Poster Session. New York University, New York, NY, June 25, 2003.
Berger, T. D., Martelli, M., Su, M., Aguayo, M., Majaj, N. J., & Pelli, D. G. (2003). Reading quickly in the periphery [Abstract]. Journal of Vision, 3(9):806, http://journalofvision.org/3/9/806/, doi:10.1167/3.9.806. [Vision Sciences Society, Sarasota, Florida, May 2003] Published as Pelli, Tillman, Freeman, Su, Berger, & Majaj (2007). Majaj, N. J., Liang, Y. X., Martelli, M., Berger, T. D., & Pelli, D. G. (2003). Channel for reading [Abstract]. Journal of Vision, 3(9):813, http://journalofvision.org/3/9/813/, doi:10.1167/3.9.813. [Vision Sciences Society, Sarasota, Florida, May 2003] Martelli, M., Silla, S., Majaj, N. J., & Pelli, D. G. (2003). Complexity impairs efficiency in the periphery [Abstract]. Journal of Vision, 3(9):505, http://journalofvision.org/3/9/505/, doi:10.1167/3.9.505. [Vision Sciences Society, Sarasota, Florida, May 2003] Pelli, D. G., Martelli, M., Majaj, N. J., & Berger, T. D. (2003). One channel per object? [Abstract]. Journal of Vision, 3(9):267, http://journalofvision.org/3/9/267/, doi:10.1167/3.9.267. [Vision Sciences Society, Sarasota, Florida, May 2003] Mishra, A., Baweja, G., Martelli, M., Chen, I., Fox, J., Majaj, N. J., & Pelli, D. G. (2002) How efficiency for identifying objects improves with age. European Conference on Visual Perception, Glasgow, August 2002. Pelli, D., Lee, M. H., Martelli, M., & Majaj, N. J. (2002). The orientation filter we use to identify objects: object recognition by a donut [Abstract]. Journal of Vision, 2(7):699, http://journalofvision.org/2/7/699/, doi:10.1167/2.7.699. [Vision Sciences Society, Sarasota, Florida, May 10-15, 2002] Martelli, M., Majaj, N. J., & Pelli, D. (2002). Words and faces: eccentricity distinguishes crowding from context [Abstract]. Journal of Vision, 2(7):608, http://journalofvision.org/2/7/608/, doi:10.1167/2.7.608. [Vision Sciences Society, Sarasota, Florida, May 10-15, 2002]
Published as Martelli, Majaj, and Pelli (2005).Pelli, D. G., & Palomares, M. (2000). The role of feature detection in crowding. Investigative Ophthalmology and Visual Science, 41, S37. ABSTRACT. A letter in the periphery is much harder to identify in the presence of neighboring letters. This is crowding. Last year we showed that crowding in utterly unlike ordinary masking, having a very steep contrast response and lacking channel-like selectivity (Palomares et al., ARVO '99). We now report that the effect of each flanking letter on the threshold contrast for identification of the target letter is all or none, dependent on target-flank separation but independent of suprathreshold flank contrast. This is evidence that the interference occurs at a second stage, between detected features.
Palomares, M., LaPutt, M. C., & Pelli, D. G. (1999). Crowding is unlike ordinary masking. Investigative Ophthalmology and Visual Science, 40, 1864. ABSTRACT. Operationally, masking is the effect of a “mask” pattern on visibility of a signal. Usually the signal threshold is proportional (log-log slope of 1) to mask contrast, or nearly so (log-log slope of 0.65). And masks are usually effective only if they overlap the signal. In the periphery, small letters are much harder to identify in the presence of nearby letters. This is crowding. At 4° viewing eccentricity, we find that threshold contrast for identification of a 0.25° signal letter is elevated 10-fold by mask letters anywhere in a 2.5° region, ten times wider than the signal. Threshold is a sigmoidal function of flank contrast, with a log-log slope of 2. If the signal is instead masked by white noise, noise is effective only over the 0.25° region of the signal itself and threshold is proportional to mask contrast. These results and observers’ introspections suggest that the noise mask interferes with feature detection while crowding represents inappropriate combination of detected features.
Bayer, H. M., Schwartz, O., & Pelli, D. (1998). Recognizing facial expressions efficiently. Investigative Ophthalmology and Visual Science, 39, ?. ABSTRACT. The roles of facial features and spatial frequencies in the recognition of facial expressions have been studied separately, but not together. We measured efficiency for observers performing a 21-way facial expression identification task. Baseline efficiency for the original photos was only 2%. We wondered if human performance would improve by limiting the differences between stimuli to a critical spatial frequency range and area as determined by Schwartz, et al. Limiting the differences to the critical spatial frequency band centered at 8 cycles/face width improved efficiency to 4%. When images differed only within a critical area that included the mouth and the edge of the cheek, efficiency increased to 6%. Finally, by limiting the differences to the critical spatial frequencies within the critical region, we reached an efficiency of 9%.
Palomares, M., Cardazone, G., Green, J., LaPutt, M. C., Majaj, N. J., Pelli, D. G., & Levi, D. M. (1998). Letter identification is channel mediated, but crowding isn't. Investigative Ophthalmology and Visual Science, 39, 833. ABSTRACT. Crowding is often described as contour interaction, implying that the crowding effect is due to interference between neighboring features. Using critical-band masking, Majaj et al. (ARVO ‘97) showed that letter identification is mediated by a spatial frequency channel whose center frequency falls as the -0.7 power of letter size. We measured critical spacing: the minimum spacing between letters required to eliminate the effect of crowding. Interference within a channel ought to extend over a fixed number of periods of the channel’s center frequency, predicting that critical spacing should be proportional to the 0.7 power of letter size. Instead, we find that critical spacing is directly proportional to letter size, and identical in foveal, peripheral, and amblyopic vision. Replacing a letter S by its outline S doubles its line frequency, and doubles the channel frequency. Yet we find the same critical spacing for crowding of a letter by either regular or outline letters. The finding that crowding is characterized by the scale of the whole letter, rather than that of its features, indicates that crowding represents interference at the level of recognizing the whole pattern rather than detection of individual features.
Schwartz, O., Bayer, H. M., & Pelli, D. (1998). Features, frequencies, and facial expressions. Investigative Ophthalmology and Visual Science, 39, ?. ABSTRACT. We find that only a particular range of spatial frequencies and spatial features is required to identify facial expressions (1 of 21). Critical spatial frequencies are obtained by varying the cut-off frequency of lowpass and highpass noise; critical features are obtained by varying the cut-off spatial postion of a horizontal and vertical noise curtain. The critical region in frequency and space is a band centered at 8 cycles per face width, stretching horizontally from the tip of the lips to the edge of the cheek and vertically from the bottom of the nose to the chin. The photo illustrates the critical information that we found. It is constructed by using one fixed face as the background and pasting onto it part of one of the 21 images, just in the required region and frequency range.
Pelli, D., Majaj, N., & Glimcher, P. (1997). Where is the 7±2 category bottleneck? Investigative Ophthalmology and Visual Science, 38(4).
ABSTRACT. It is well known that observers classifying signals varying along a single sensory dimension can only distinguish 7±2 categories (Miller, 1956). We wondered whether eye movements could escape this apparently cognitive bottleneck. In a dark room, the observer fixated a point of light, which was suddenly displaced horizontally by a random offset, and extinguished 150 ms later. The dual task required the observer to shift gaze to the brief target and to then verbally report the offset in cm. Amplitude of the saccadic eye movement was recorded by a scierai search coil. Preliminary results are surprising. On the one hand, the eye movements of both observers are no more accurate than their verbal reports. On the other hand, only the verbal reports showed the expected increase in precision when the stimulus range was reduced from 10-30 deg to 17.5-22.5 deg.
Pelli, D. G. (1997) Two stages of perception. Paper presented at Theories of Vision symposium at New York University, New York City, October 17, 1997. Raghavan, M., & Pelli, D. G. (1995). Psychophysical evidence for cortical noise. Investigative Ophthalmology and Visual Science, 36(4), s905.
(poster) doi: 10.7490/f1000research.1115199.1 https://f1000research.com/posters/7-29ABSTRACT. The extent of spatial and temporal integration in the visual system can be examined by measuring contrast thresholds as a function of the size and duration of signals. We measured the contrast thresholds for identifying letters and sine gratings on blank and noisy backgrounds. The noise was dynamic, uncorrelated over space and time. We find that for high spatial frequency gratings and small letters, thresholds as a function of duration is well fit by supposing a 150 ms integrator. Thresholds drop with duration both with and without display noise indicating that sensitivity to high spatial frequency signals is determined by an early (photon?) noise that can be integrated out. However, for low spatial frequency gratings and large letters, thresholds drop with duration only in the presence of display noise. This finding can only be explained if thresholds for low spatial frequency signals is determined by a late noise that lies after spatio-temporal integration, presumably in the cortex.
Pelli, D. G., Raghavan, M., & Ahuja, S. (1995). The noises that limit visual perception. Investigative Ophthalmology and Visual Science, 36(4), s851.
Cornelissen, F. W., Pelli, D. G., Farell, B., & Szeverenyi, N. (1995) fMRI of contrast response in visual cortex. Human Brain Mapping, 1 (Suppl. 1), 45. Pelli, D. G. (1992) The quantum efficiency of human vision: comparing psychophysics and anatomy. Soc. Neurosci. Abstr., 18 (2), 1396.
ABSTRACT. Transduction efficiency (fraction of corneal photons that produce an isomerization) has received much attention since the time of Hecht, but is still subject to much uncertainty. Pelli (1990) introduced a new psychophysical technique that measures transduction efficiency by measuring the effects of visual noise masking. The X's show preliminary measurements indicating peak transduction efficiencies of 5-10% for both rods and cones. They agree with anatomical estimates shown as curves, which are computed from the known number of receptors and their optical densities and aperture sizes.
Pelli, D. G. (1990) Regional variation in scotopic transduction efficiency. Investigative Ophthalmology & Visual Science, 31 (suppl). 494. Pelli, D. G. (1981) The effect of uncertainty: detecting a signal at one of ten-thousand possible times and places. Supplement to Investigative Ophthalmology and Visual Science, 20, 178A. [Complete text and figures of the talk appear as Appendix 6 in my thesis: to the top
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