Perception as Practiced

1. Perception as Practiced Gadi Geiger Center for Biological and Computational Learning Brain and Cognitive Sciences Massachusetts Institute of Technology Cambridge MA 02139 gadi@ai.mit.edu

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8. The form-resolving field (FRF) of English-native adults 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees] ordinary readers (OR)

9. The form-resolving field (FRF) of English-native adults ordinary readers (OR) dyslexics 100 80 60 correct recognition [%] 40 dyslexics 20 OR 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees]

10. The form-resolving field (FRF) of English-native adults ordinary readers (OR) 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees] dyslexics the differences in recognition

11. The form-resolving field (FRF) of English-native adults ordinary readers (OR) 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees] dyslexics the extent of recognition difference

12. When ordinary readers look at text The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading.

13. When dyslexics look at text The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading.

14. Demonstrating lateral masking N x TENET Keep your gaze on the x without moving your eyes

15. The form-resolving field (FRF) of English-native adults ordinary readers (OR) dyslexics 100 80 60 correct recognition [%] 40 dyslexics 20 OR 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees]

16. The form-resolving field (FRF) of Hebrew-native adults ordinary readers (OR) 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees]

17. The form-resolving field (FRF) of Hebrew-native adults ordinary readers (OR) 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees] dyslexics dyslexics OR

18. The regimen of practice for learning a new perceptual strategy The practice comprises two parts: • Novel, small-scale, hand-eye coordination tasks like • painting, drawing, modeling, embroidery etc.. • 2. Reading with a window-mask.

19. The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading. The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading.

20. Reading with a window-mask The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading. The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading.

21. Reading with a window-mask The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading. The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading.

22. Reading with a window-mask The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading. The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey, a scribe uses a narrow field to write and a painter or architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading.

23. The form-resolving field (FRF) of English-native Dyslexics before practice 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees] before OR

24. The form-resolving field (FRF) of English-native Dyslexics before and after practice 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees] before after OR

25. The form-resolving field (FRF) of a “conditional dyslexic” In the “alert” phase 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees]

26. The form-resolving field (FRF) of a “conditional dyslexic” In the “alert” phase 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees] in the “tired” phase tired alert

28. 100 80 60 40 20 0 -15 -10 -5 0 5 10 15 Smooth and jagged letters The FRF of adult ordinary readers when presented with smooth letters correct recognition [%] angular distance from center of gaze [degrees]

29. 100 80 60 40 20 0 -15 -10 -5 0 5 10 15 Smooth and jagged letters The FRF of adult ordinary readers when presented with smooth letters jagged letters correct recognition [%] jagged smooth angular distance from center of gaze [degrees]

30. 100 80 60 40 20 0 -15 -10 -5 0 5 10 15 The form-resolving field adults Ordinary readers “speed readers” correct recognition [%] speed readers OR angular distance from center of gaze [degrees]

31. Line drawings of objects used as stimuli

32. 100 80 60 40 20 -15 -10 -5 0 5 10 15 The form-resolving field (FRF)of adult ordinary readers large letters “objects” letters correct recognition [%] objects angular distance from center of gaze [degrees]

33. Main points -Dyslexics and ordinary readers differ in their perceptual strategy. A wide strategy for dyslexics and a narrow one for ordinary readers. -Dyslexics are able to learn the narrow strategy for reading by practice. -Similarly, ordinary readers are able to learn “speed reading”. -A perceptual strategy is task-determined and is learned by practice to optimize task performance.

34. Collaborators: • Jerry Lettvin, MIT. • Olga Zegarra-Moran, SISSA, Italy • -Manfred Fahle, Tuebingen University, Germany