Study of crowding effect for stimuli of low contrast and large size in the centre of vision field

We present the results of psychophysical studies on the effect of additional images (distractors) for identification of test stimuli presented at the center of the visual field. As a test we used low contrast Landolt rings with size 1.1; 1.5 or 2.2 degre es. Distractors were Landolt rings or rings without discontinuities of the same size. Distractor would appear to the right or left of the ring in the region of 1 to 2 between the centers of the diameters of the test images. The task of the observer was in distinguishing the orientation of test Landolt rings. It is shown that the presentation of the same shape distractor degrades test recognition at a distance of up to 1,8 diameter of the Landolt test rings, which exceeds the interaction areas defined previously in the studies of the of crowding effect. Distractor in the form of a ring without gap degrades the perception on a minimum distance, in contact with the test. Errors in distinction of orientation of test Landolt rings were not accidental: observers have often pointed out the orientation of the distractor. The possible impact of integration features of images and attention on the outcome of experiments factor is discussed.

1. Atkinson J. Review of human visual development: crowding and dyslexia. Vision and visual dyslexia, London,
   1991, pp. 44–57.
2. Bernard J. B., Chung S. T. L. The dependence of crowding on flanker complexity and target–flanker
   similarity. Journal of Vision, 2011, vol. 11, no. 8, pp. 1–16. http://www.journalofvision.org/content/11/8/1, doi:10.1167/11.8.1.
3. Bondarko V. M., Danilova M. V. Krauding-effekt pri razlichnom okruzhenii i rasstoyanii mezhdu stimulami [Crowding effect for different surrounding and distance between stimuli]. Sensornye sistemy [Sensory systems (Russia)], 1996, vol. 10, no. 1, pp. 132–140 (In Russ.).
4. Bondarko V. M., Danilova M. V. Svyaz’ krauding-effekta s funktsionirovaniem vysokochastotnykh prostranstvennykh elementov [Connection of crowding-effect with work of high frequency spatial elements]. Sensornye sistemy [Sensory systems (Russia)], 2002, vol. 16, no. 2, pp. 89–99 (In Russ.).
5. Bondarko V. M., Danilova M. V., Solnushkin S. D., Chikhman V. N. Otsenka razmera zony krauding-effekta
   pri periferiinom pred”yavlenii stimulov [Estimates of the size of inhibitory areas in crowding effects in periphery]. Fiziologiya cheloveka [Human physiology (Russia)], 2014, vol. 40, no. 3, pp. 13–21 (In Russ.).
6. Bouma H. Interaction effects in parafoveal letter recognition. Nature. 1970, vol. 226, no. 5241, pp. 177–178. doi:10.1038/226177a0.
7. Chung S. T. L., Levi D. M., Legge G. E. Spatial-frequency and contrast properties of crowding. Vision Res., 2001, vol. 41, pp. 1833–1850. doi:10.1016/S0042-6989(01)00071-2.
8. Danilova M. V., Bondarko V. M. Foveal contour interactions and crowding effects. Journal of Vision, 2007, vol. 7, no. 2, pp. 1–18. http://journalofvision.org/17/12/25/, doi:10.1167/1167.1162.1125.
9. Danilova M. V., Bondarko V. M. Vliyanie konteksta na vypolnenie zadachi razlicheniya orientatsii
   pryamougol’nykh reshetok na predele razresheniya zritel’noi sistemy [Infuence of context to discrimination of orientations of squared gratings at the resolution limit of visual system]. Sensornye sistemy [Sensory systems (Russia)], 2002, vol. 16, no. 2, pp. 100–109 (In Russ.).
10. Ehlers H. Clinical testing of visual acuity. AMA Archives of Ophthalmology, 1953, vol. 49, no. 4, pp. 431–434. doi:10.1001/archopht.1953.00920020441007.
11. Ehrt O., Hess R. Foveal contour interaction: detection and discrimination. J. Opt. Soc. Am. A, 2005, vol. 22, pp. 209-216. doi:10.1364/JOSAA.22.000209.
12. Flom M. C. Contour interaction and the crowding effect. Problems in Optometry. 1991, vol. 3, no. 2., pp. 237–257.
13. Flom M. C., Heath G. G., Takahashi E. Contour interaction and visual resolution: contralateral effects. Science, 1963, vol. 142, no. 3594, pp. 979-980. doi:10.1126/science.142.3594.979.
14. Flom M. C., Weymouth F.W., Kahneman D. Visual resolution and contour interaction. J. Opt. Soc. Am., 1963, vol. 53, no. 9, pp. 1026–1032. doi:10.1364/JOSA.53.001026.
15. Freeman J., Chakravarthi R., Pelli D. G. Substitution and pooling in crowding. Atten. Percept. Psychophys., 2012, vol. 74, pp. 379–396. doi:10.3758/s13414-011-0229-0.
16. Hanus D., Vul E. Quantifying error distributions in crowding. Journal of Vision, 2013, vol. 13, no. 4, pp. 1–27. doi:10.1167/13.4.17.
17. He S., Cavanagh P., Intriligator J. Attentional resolution and the locus of visual awareness. Nature, 1996, vol. 383, pp. 334–336. doi:10.1038/383334a0.
18. Hess R. F., Jacobs R. J. A preliminary report of acuity and contour interactions across the amblyope's visual field. Vision Research, 1979, vol. 19, pp. 1403–1408. doi:10.1016/0042-6989(79)90214-1.
19. Kooi F. L., Toet A., Tripathy S. P., Levi D. M. The effect of similarity and duration on spatial interaction in peripheral vision. Spatial Vision, 1994, vol. 8, no. 2, pp. 255–279. doi:10.1163/156856894X00350.
20. Levi D. M. Crowding—An essential bottleneck for object recognition: A mini-review. Vision Res., 2008, vol. 48, pp. 635–654. doi:10.1167/2.2.3.
21. Levi D. M., Klein S. A., Hariharan S. Suppressive and facilitatory spatial interactions in foveal vision: foveal crowding is simple contrast masking. Journal of Vision, 2002, vol. 2, pp. 140–166. doi:10.1016/j. visres.2007.12.009.
22. Parkes L., Lund J., Angelucci A., Solomon J., Morgan M. Compulsory averaging of crowded orientation signals in human vision. Nature Neuroscience, 2001, vol. 4, no. 7, pp. 739–744. doi:10.1038/89532.
23. Pelli D. G. Crowding: A cortical constraint on object recognition. Current opinion in neurobiology, 2008, vol. 18, no. 4, pp. 445–451. doi:10.1016/j.conb.2008.09.008.
24. Pelli D. G., Palomares M., Majaj N. J. Crowding is unlike ordinary masking: distinguishing feature detection and integration. Journal of Vision, 2004, vol. 4, pp. 1136–1169. doi:10.1167/4.12.12.
25. Pelli D. G., Tillman K. A. The uncrowded window of object recognition. Nature Neuroscience, 2008, vol. 11, pp. 1129–1135. doi:10.1038/nn1208-1463 b.
26. Strasburger H., Harvey L. O., Jr., Rentchler I. Contrast thresholds for identification of numeric characters in direct and eccentric view. Perception & Psychophysics, 1991, vol. 49, no. 6, pp. 495–508. doi:10.3758/BF03212183.
27. Strasburger H., Rentschler I., Juttner M. Peripheral vision and pattern recognition: A review. Journal of Vision, 2011, vol. 11, no. 5, pp. 1–30. doi:10.1167/11.5.13.
28. Townsend J. T., Taylor S. G., Brown D. R. Lateral masking for letters with unlimited viewing time. Perception and Psychophysics, 1971, vol. 10, no. 5, pp. 375–378. doi:10.3758/BF03207464.
29. Tripathy S. P., Cavanagh P., Bedell H. E. Large crowding zones in peripheral vision for briefly presented stimuli. Journal of Vision, 2014, vol. 14, no. 6. doi:10.1167/14.6.11.
30. Wetherill G. B., Levitt H. Sequential estimation of points on a psychometric function. British Journal of Mathematical and Statistical Psychology, 1965, vol. 18, pp. 1–10. doi:10.1111/j.2044-8317.1965.tb00689.x.
31. Woodrow H. The effect of pattern upon simultaneous letter-span. Am. J. Psychology, 1938, vol. 51, pp. 83–96. doi:10.2307/1416417.