Methods and apparatus for diagnosing and remediating reading disorders

• US 6,045,515 A
• Filed: 04/07/1998
• Issued: 04/04/2000
• Est. Priority Date: 04/07/1997
• Status: Expired due to Term

• Current Assignee: Teri A. Lawton
• Original Assignee: Teri A. Lawton
• Inventors: Lawton, Teri A.
• Primary Examiner(s): O'Connor, Cary
• Assistant Examiner(s): MARMOR II, CHARLES ALAN
• Application Number:
  US09/056,839
• Time in Patent Office: 728 Days
• Field of Search: 600/558, 351/211, 351/223, 351/239, 351/243
• US Class Current: 600/558
• CPC Class Codes: A61B 3/022 for testing contrast sensitivity
• CPC Class Codes: A61B 3/032 Devices for presenting test symbols or characters, e.g. test chart projectors A61B3/036 takes precedence
• CPC Class Codes: A61B 3/06 for testing light sensitivity, e.g. adaptation; for testing colour vision
• CPC Class Codes: A61H 5/00 Exercisers for the eyes
• CPC Class Codes: G16H 15/00 ICT specially adapted for medical reports, e.g. generation or transmission thereof
• CPC Class Codes: G16H 20/70 relating to mental therapies, e.g. psychological therapy or autogenous training

Abstract

Reading disorders are diagnosed and remediated in a subject by respectively measuring and improving contrast sensitivity for motion discrimination of the subject. A background is displayed on a monitor with a contrast and a spatial frequency. A test window is superimposed over the background and includes a test pattern with a contrast and a spatial frequency. The contrasts and the spatial frequencies are within respective ranges which stimulate the visual cortical movement system of the subject. The test pattern is then moved within the test window. The subject provides a signal indicative of the direction the subject believes the test pattern moved. In response to this signal, the contrast of the test pattern, the spatial frequency of the background, or the spatial frequency of the test pattern is modified, either by increasing or decreasing its respective value. This process is then repeated a number of times, cycling through predetermined combinations of test patterns and backgrounds. Contrast sensitivity may be measured to determine whether a child is dyslexic. Repeated stimulation by the methods and apparatus of the invention improves contrast sensitivity, thereby remediating dyslexia and improving reading ability.

Claims

1. A method for diagnosing dyslexia by measuring contrast sensitivity for motion discrimination of a subject having a visual cortical movement system, said method comprising the steps of:

(a) displaying a background with a contrast and a spatial frequency;

(b) displaying a test window within said background, said test window including a test pattern with a contrast and a spatial frequency, said test pattern replacing said background;

said contrasts being within a range which stimulates the visual cortical movement system of the subject;

said spatial frequencies being within a range which stimulates the visual cortical movement system of the subject;

(c) moving said test pattern within said test window in either a first direction or a second direction;

(d) receiving a signal from the subject indicative of either said first direction or said second direction;

(e) modifying at least one of said contrasts or said spatial frequencies in response to said signal;

(f) repeating steps (a) through (e); and

(g) using the signals from the subject as criteria for forming a diagnosis of dyslexia.

2. A method as claimed in claim 1 wherein said step of displaying a test window comprises the step of:

displaying said test pattern with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said test pattern including spatial frequencies ranging from about 0.25 cycle per degree to about 2 cycles per degree.

3. A method as claimed in claim 2 wherein said step of displaying a background comprises the step of:

displaying said background with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said background including spatial frequencies that are 1/4, 1/2, 1, 2, and 4 times said spatial frequency at which said test pattern is displayed.

4. A method as claimed in claim 3 wherein said modifying step comprises the steps of:

increasing said contrast of said test pattern if said signal is incorrect; and

decreasing said contrast of said test pattern if said signal is correct.

5. A method as claimed in claim 4, wherein said step of modifying further comprises the steps of:

varying said spatial frequency at which said background is displayed while maintaining constant said spatial frequency at which said test pattern is displayed.

6. A method as claimed in claim 5, wherein said step of modifying further comprises the steps of:

varying said spatial frequency at which said test pattern is displayed after said spatial frequency of said background is varied through each of said spatial frequencies of said predetermined range of spatial frequencies.

7. The method of claim 4, wherein the contrast of said test pattern is decreased only when a sequential number of signals are correct.

8. The method of claim 7, wherein the number is three.

9. A method as claimed in claim 1 wherein:

said step of displaying a background comprises the step of displaying said background at a contrast selected from a predetermined range of contrasts; and

said step of displaying a test window comprises the step of displaying said test pattern at a contrast selected from a predetermined range of contrasts;

said predetermined ranges of contrasts including contrasts of less than about 10%.

10. A method as claimed in claim 9, wherein said step of displaying a background comprises the step of:

displaying said background at a contrast of about 5%.

11. A method as claimed in claim 1 wherein:

said step of displaying a test window comprises the step of displaying said test pattern at an initial position within said test window for a predetermined period; and

said step of moving comprises the step of displaying said test pattern at a final position within said test window for a predetermined period.

12. A method as claimed in claim 11, wherein:

said step of displaying said test pattern at an initial position comprises the step of displaying said test pattern for less than about 0.2 second; and

said step of displaying said test pattern at a final position comprises the step of displaying said test pattern for less than about 0.2 second.

13. A method as claimed in claim 11, wherein:

said step of displaying a background comprises the step of displaying said background as substantially vertical stripes which alternate sinusoidally between light and dark at said spatial frequency; and

said step of displaying a test window comprises the step of displaying said test pattern as substantially vertical stripes which alternate sinusoidally between light and dark at said spatial frequency.

14. A method as claimed in claim 8 wherein said step of moving comprises the step of displaying said test pattern at said final position, said second position being either to the right or to the left of said first position;

said predetermined periods at which said test pattern is displayed at said initial and final positions being of a duration to induce in the subject an apparent sense of motion of said stripes moving right or left from said initial position to said final position.

15. A method as claimed in claim 1 wherein said method diagnoses dyslexia by measuring an absolute value of the contrast sensitivity for motion discrimination.

16. A method as claimed in claim 15, further comprising the steps of:

storing data based on said signals received from the subject; and

determining the contrast sensitivity based on said data.

17. A method as claimed in claim 1 wherein said method diagnoses dyslexia by measuring contrast sensitivity for motion discrimination to yield a contrast sensitivity function with a shape.

18. A method as claimed in claim 1 wherein said method further improves the contrast sensitivity function for motion discrimination of the subject.

19. A method as claimed in claim 1 wherein said method further improves reading rate of the subject by improving the contrast sensitivity for motion discrimination.

20. Apparatus for improving contrast sensitivity for movement discrimination of a subject having a visual cortical movement system, said apparatus comprising:

a monitor; and

a computer connected to said monitor, said computer being configured to;

(a) display a background with a contrast and a spatial frequency;

(b) display a test window within said background, said test window including a test pattern with a contrast and a spatial frequency said test pattern replacing said background;

said contrasts being within a range which stimulates the visual cortical movement system of the subject;

said spatial frequencies being within a range which stimulates the visual cortical movement system of the subject;

(c) move said test pattern within said test window in either a first direction or a second direction;

(d) receive a signal from the subject indicative of either said first direction or said second direction;

(e) modify at least one of said contrasts or said spatial frequencies in response to said signal; and

(f) repeat steps (a) through (e) a plurality of times.

21. The apparatus of claim 20, operated to improve contrast sensitivity for movement discrimination of a subject having a visual cortical movement system.

22. The apparatus of claim 20 operated to improve the reading rare of a subject having a visual cortical movement system.

23. Apparatus as claimed in claim 20, wherein said computer is further configured to display said test pattern with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said test pattern including spatial frequencies ranging from about 0.25 cycle per degree to about 2 cycles per degree.

24. Apparatus as claimed in claim 23, wherein said computer is configured to display said background with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said background including spatial frequencies that are 1/4, 1/2, 1, 2, and 4 times said spatial frequency at which said test pattern is displayed.

25. Apparatus as claimed in claim 20, wherein said computer is configured to:

display said background at a contrast selected from a predetermined range of contrasts; and

display said test pattern at a contrast selected from a predetermined range of contrasts;

said predetermined ranges of contrasts including contrasts of less than about 10%.

26. Apparatus as claimed in claim 25, wherein said computer is configured to display said background at a contrast of about 5%.

27. Apparatus as claimed in claim 20, wherein said computer is configured to:

display said test pattern at an initial position within said test window for a predetermined period; and

display said test pattern at a final position within said test window for a predetermined period.

28. Apparatus as claimed in claim 27, wherein said computer is configured to display said test pattern at both of said positions for less than about 0.2 second.

29. Apparatus as claimed in claim 20, wherein said computer is configured to vary said contrast at which said test pattern is displayed.

30. Apparatus as claimed in claim 29, wherein said computer is configured to vary said spatial frequency at which said background is displayed.

31. Apparatus as claimed in claim 30, wherein said computer is configured to vary said spatial frequency at which said test pattern is displayed.

32. Apparatus as claimed in claim 20, wherein said computer is further configured to display a blank field on said monitor before displaying said background and after moving said test pattern.

33. Apparatus as claimed in claim 20, wherein said test window is substantially circular.

34. Apparatus as claimed in claim 20, wherein said background is substantially larger than said test window.

35. Apparatus as claimed in claim 20, wherein said computer is configured to display said field such that said test is about 20% as large as said background.

36. The apparatus of claim 20, wherein the contrast of the test pattern is increased if the signal is incorrect, and wherein the contrast of the test pattern is decreased if the signal is correct.

37. The apparatus of claim 36, wherein the contrast of said test pattern is decreased only when a sequential number of signals are correct.

38. The apparatus of claim 37, wherein the number is three.

39. An article of manufacture comprising:

storage medium readable by a computer; and

plurality of instructions stored on said storage medium and including instructions for;

(a) configuring the computer to display on a monitor a background with a contrast and a spatial frequency;

(b) configuring the computer to display on a monitor a test window within said background, said test window including a test pattern with a contrast and a spatial frequency, said test pattern replacing said background pattern;

said contrasts being within a range which stimulates the visual cortical movement system of the subject;

said spatial frequencies being within a range which stimulates the visual cortical movement system of the subject;

(d) configuring the computer to move said test pattern within said test window in either a first direction or a second direction;

(e) configuring the computer to receive, via an input device connected to the computer, from a subject a signal indicative of either said first direction or said second direction; and

(f) configuring the computer to modify at least one of said contrasts or spatial frequencies in response to said signal; and

(g) configuring said computer to repeat steps (a) through (f).

40. A method for improving contrast sensitivity for motion discrimination of a subject having a visual cortical movement system, said method comprising the steps of:

(a) displaying a background with a contrast and a spatial frequency;

(b) displaying a test window within said background, said test window including a test pattern with a contrast and a spatial frequency, said test pattern replacing said background;

said contrasts being within a range which stimulates the visual cortical movement system of the subject;

said spatial frequencies being within a range which stimulates the visual cortical movement system of the subject;

(c) moving said test pattern within said test window in either a first direction or a second direction;

(d) receiving a signal from the subject indicative of either said first direction or said second direction;

(e) modifying at least one of said contrasts or said spatial frequencies in response to said signal;

(f) repeating steps (a) through (e).

41. A method as claimed in claim 40, wherein said step of displaying a test window comprises the step of:

displaying said test pattern with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said test pattern including spatial frequencies ranging from about 0.25 cycle per degree to about 2 cycles per degree.

42. A method as claimed in claim 41, wherein said step of displaying a background comprises the step of:

displaying said background with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said background including spatial frequencies that are 1/4, 1/2, 1, 2, and 4 times said spatial frequency at which said test pattern is displayed.

43. A method as claimed in claim 42, wherein said modifying step comprises the steps of:

increasing said contrast of said test pattern if said signal is incorrect; and

decreasing said contrast of said test pattern if said signal is correct.

44. A method as claimed in claim 43, wherein said step of modifying further comprises the steps of:

varying said spatial frequency at which said background is displayed while maintaining constant said spatial frequency at which said test pattern is displayed.

45. A method as claimed in claim 44, wherein said step of modifying further comprises the steps of:

varying said spatial frequency at which said test pattern is displayed after said spatial frequency of said background is varied through each of said spatial frequencies of said predetermined range of spatial frequencies.

46. The method of claim 43, wherein the contrast of said test pattern is decreased only when a sequential number of signals are correct.

47. The method of claim 46, wherein the number is three.

48. The method of claim 47, wherein the contrast of said test pattern is decreased only when a sequential number of signals are correct.

49. The method of claim 48, wherein the number is three.

50. A method as claimed in claim 40, wherein:

said step of displaying a background comprises the step of displaying said background at a contrast selected from a predetermined range of contrasts; and

said step of displaying a test window comprises the step of displaying said test pattern at a contrast selected from a predetermined range of contrasts;

said predetermined ranges of contrasts including contrasts of less than about 10%.

51. A method as claimed in claim 50, wherein said step of displaying a background comprises the step of:

displaying said background at a contrast of about 5%.

52. A method as claimed in claim 40, wherein:

said step of displaying a test window comprises the step of displaying said test pattern at an initial position within said test window for a predetermined period; and

said step of moving comprises the step of displaying said test pattern at a final position within said test window for a predetermined period.

53. A method as claimed in claim 52, wherein:

said step of displaying a background comprises the step of displaying said background as substantially vertical stripes which alternate sinusoidally between light and dark at said spatial frequency; and

said step of displaying a test window comprises the step of displaying said test pattern as substantially vertical stripes which alternate sinusoidally between light and dark at said spatial frequency.

54. A method as claimed in claim 53, wherein said step of moving comprises the step of displaying said test pattern at said final position, said second position being either to the right or to the left of said first position;

said predetermined periods at which said test pattern is displayed at said initial and final positions being of a duration to induce in the subject an apparent sense of motion of said stripes moving right or left from said initial position to said final position.

55. A method as claimed in claim 52, wherein:

said step of displaying said test pattern at an initial position comprises the step of displaying said test pattern for less than about 0.2 second; and

said step of displaying said test pattern at a final position comprises the step of displaying said test pattern for less than about 0.2 second.

56. A method for improving reading speed of a subject having a visual cortical movement system, said method comprising the steps of:

(a) displaying a background with a contrast and a spatial frequency;

(b) displaying a test window within said background, said test window including a test pattern with a contrast and a spatial frequency, said test pattern replacing said background;

said contrasts being within a range which stimulates the visual cortical movement system of the subject;

said spatial frequencies being within a range which stimulates the visual cortical movement system of the subject;

(c) moving said test pattern within said test window in either a first direction or a second direction;

(d) receiving a signal from the subject indicative of either said first direction or said second direction;

(e) modifying at least one of said contrasts or said spatial frequencies in response to said signal; and

(f) repeating steps (a) through (e).

57. A method as claimed in claim 56, wherein said step of displaying a test window comprises the step of:

displaying said test pattern with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said test pattern including spatial frequencies ranging from about 0.25 cycle per degree to about 2 cycles per degree.

58. A method as claimed in claim 57, wherein said step of displaying a background comprises the step of:

displaying said background with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said background including spatial frequencies that are 1/4, 1/2, 1, 2, and 4 times said spatial frequency at which said test pattern is displayed.

59. A method as claimed in claim 58, wherein said modifying step comprises the steps of:

increasing said contrast of said test pattern if said signal is incorrect; and

decreasing said contrast of said test pattern if said signal is correct.

60. A method as claimed in claim 59, wherein said step of modifying further comprises the steps of:

varying said spatial frequency at which said background is displayed while maintaining constant said spatial frequency at which said test pattern is displayed.

61. A method as claimed in claim 60, wherein said step of modifying further comprises the steps of:

varying said spatial frequency at which said test pattern is displayed after said spatial frequency of said background is varied through each of said spatial frequencies of said predetermined range of spatial frequencies.

62. A method as claimed in claim 56, wherein:

said step of displaying a background comprises the step of displaying said background at a contrast selected from a predetermined range of contrasts; and

said step of displaying a test window comprises the step of displaying said test pattern at a contrast selected from a predetermined range of contrasts;

said predetermined ranges of contrasts including contrasts of less than about 10%.

63. A method as claimed in claim 62, wherein said step of displaying a background comprises the step of:

displaying said background at a contrast of about 5%.

64. A method as claimed in claim 56, wherein:

said step of displaying a test window comprises the step of displaying said test pattern at an initial position within said test window for a predetermined period; and

said step of moving comprises the step of displaying said test pattern at a final position within said test window for a predetermined period.

65. A method as claimed in claim 64, wherein:

said step of displaying said test pattern at an initial position comprises the step of displaying said test pattern for less than about 0.2 second; and

said step of displaying said test pattern at a final position comprises the step of displaying said test pattern for less than about 0.2 second.

66. A method as claimed in claim 64, wherein:

said step of displaying a background comprises the step of displaying said background as substantially vertical stripes which alternate sinusoidally between light and dark at said spatial frequency; and

said step of displaying a test window comprises the step of displaying said test pattern as substantially vertical stripes which alternate sinusoidally between light and dark at said spatial frequency.

67. A method as claimed in claim 66, wherein said step of moving comprises the step of displaying said test pattern at said final position, said second position being either to the right or to the left of said first position;

said predetermined periods at which said test pattern is displayed at said initial and final positions being of a duration to induce in the subject an apparent sense of motion of said stripes moving right or left from said initial position to said final position.

68. Apparatus for diagnosing dyslexia by measuring contrast sensitivity for movement discrimination of a subject having a visual cortical movement system, said apparatus comprising:

a monitor; and

a computer connected to said monitor, said computer being configured to;

(a) display a background with a contrast and a spatial frequency;

(b) display a test window within said background, said test window including a test pattern with a contrast and a spatial frequency, said test pattern replacing said background;

said contrasts being within a range which stimulates the visual cortical movement system of the subject;

said spatial frequencies being within a range which stimulates the visual cortical movement system of the subject;

(c) move said test pattern within said test window in either a first direction or a direction;

(d) receive a signal from the subject indicative of either said first direction or said second direction;

(e) modify at least one of said contrasts and/or said spatial frequencies in response to said signal;

(f) repeat steps (a) through (e) a plurality of times; and

(g) use the signals from the subject as criteria for forming a diagnosis of dyslexia.

69. Apparatus as claimed in claim 68, wherein said computer is further configured to display said test pattern with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said test pattern including spatial frequencies ranging from about 0.25 cycle per degree to about 2 cycles per degree.

70. Apparatus as claimed in claim 69, wherein said computer is configured to display said background with a spatial frequency selected from a predetermined range of spatial frequencies;

said predetermined range of spatial frequencies of said background including spatial frequencies that are 1/4, 1/2, 1, 2, and 4 times said spatial frequency at which said test pattern is displayed.

71. Apparatus as claimed in claim 68, wherein said computer is configured to:

display said background at a contrast selected from a predetermined range of contrasts; and

display said test pattern at a contrast selected from a predetermined range of contrasts;

said predetermined ranges of contrasts including contrasts of less than about 10%.

72. Apparatus as claimed in claim 71, wherein said computer is configured to display said background at a contrast of about 5%.

73. Apparatus as claimed in claim 68, wherein said computer is configured to:

display said test pattern at an initial position within said test window for a predetermined period; and

display said test pattern at a final position within said test window for a predetermined period.

74. Apparatus as claimed in claim 73, wherein said computer is configured to display said test pattern at both said positions for less than about 0.2 second.

75. Apparatus as claimed in claim 68, wherein said computer is configured to vary said contrast at which said test pattern is displayed.

76. Apparatus as claimed in claim 75, wherein said computer is configured to vary said spatial frequency at which said background is displayed.

77. Apparatus as claimed in claim 76, wherein said computer is configured to vary said spatial frequency at which said test pattern is displayed.

78. Apparatus as claimed in claim 68, wherein said computer is further configured to display a blank field on said monitor before displaying said background and after moving said test pattern.

79. Apparatus as claimed in claim 68, wherein said test window is substantially circular.

80. Apparatus as claimed in claim 68, wherein said background is substantially larger than said test window.

81. Apparatus as claimed in claim 68, wherein said computer is configured to display said field such that said test is about 20% as large as said background.

82. Apparatus as claimed in claim 68 wherein dyslexia is diagnosed by measuring an absolute value of the contrast sensitivity for motion discrimination.

83. Apparatus as claimed in claim 68, wherein dyslexia is diagnosed by measuring contrast sensitivity for motion discrimination to yield a contrast sensitivity function with a shape.

84. The apparatus of claim 68 wherein the contrast of the test pattern is increased if the signal is incorrect, and wherein the contrast of the test pattern is decreased if the signal is correct.

85. The apparatus of claim 84, wherein the contrast of said test pattern is decreased only when a sequential number of signals are correct.

86. The apparatus of claim 85, wherein the number is three.