This document summarizes assistive technologies for individuals with spinal cord injuries. It describes traditional devices like keyboards, mice, trackballs, switches and pointers that use physical interaction. It also covers sound-based, tracking and myographic interfaces that respond to speech, head/eye movement or muscle signals. The document discusses various brain-computer interface approaches using EEG, MEG, fMRI and other neural signals. It evaluates different technologies based on factors like direct selection vs scanning input, speed, accuracy and acceptance. While many options exist, the document concludes that assistive technologies remain highly limited overall.

1. A Survey
ASSISTIVE TECHNOLOGIES FOR
SPINAL CORD INJURED
INDIVIDUALS
December / 2007 Tiago Guerreiro

2. Tradicional Devices
Tradicional Interactions

7. What about
the Others?

8. Spinal Cord
largest nerve in the body
carry messages between
brain and the spinal
nerves

11. We have the whole world in our hands.

13. Assistive
Technologies

15. Potential Users

16. Direct Selection Scanning Encoding
Dimensionality and Input Speed

17. Accuracy

18. Ease of use

19. Aesthetics, Hygiene and Acceptance

20. Mobility Adequacy

21. Maturity, Availability and Cost

22. Soft
Adaptations

23. Expanded Keyboards
Compact Keyboards
Keyguards
Typing Aids (Sticks)

24. Trackballs
Alternative Mice
Joysticks
Touchpads

25. Mouse emulators
Sticky Keys
Bounce Keys
Invisible Keyguard
On-Screen Keyboards Key Repeat Time
Key Hold Time
Key Mouse

28. Switches, Sticks and Pointers

29. Button switch
Thumb switch Finger tip Switch
(Shannon et al, 1981)
Multiple Switches

30. TonguePoint
(Salem and Zhai, 1997)
Bite switch
Jouse2 – Joystick-operated Mouse

31. Cheek Switch
Stick
Head Switch

32. Switches, Sticks and Pointers

33. Sound‐Based Interfaces

34. Motivation
natural and extensive
high dimensionality
direct selection
works if consistent…

35. Speech
recognition errors
inadequate for continous control
target‐based solutions error prone
(Dai et al,, 2004)

36. Speech Keyboards
letters (PA) and frequent words
(Dabbagh and Damper, 1985)
row‐column encoding
(Dabbagh and Damper, 1985)
(Su and Chung, 2001)

37. Speech Mouse
direction‐based solutions
predictive cursor
(Karimullah and Sears, 2002)
grid‐based solutions
(Dai et al., 2004)

39. Wheelchair Control
some attempts
(Youdin et al., 1980) (Mazo et al., 1995)
difficult and dangerous
(Simpson et al., 2002)
limited time range
(Amori et al., 1992)
proximity sensors
(Simpson et al., 1992)

40. Environmental Control
normally non‐critical
two level encoding selection
(Damper, 1986)
emergency mechanical switch
(Carvalho et al., 1999)

41. (Igarashi and Hughes, 2001)

42. Vocal Joystick (Bilmes et al., 2006)
Accoustic Mouse Pointer (Sporka et al., 2006)

43. Aural Flow Monitoring
(Vaidyanathan et al., 2006; Vaidyanathan et al., 2007)
tooth‐touch sound
(Kuzume and Morimoto, 2006)

44. Sound Interfaces

45. Tracking Interfaces

47. Electrooculography

48. Relative mapping
(Norris and Wilson, 1997)
EagleEyes (Gips et al., 1996)
(Manabe and Fukumoto, 2006)
(Barea et al., 2002)

49. Head Optical Pointers
(Chen et al., 2007)
Lomak
Nod and Shake
(Hamman et al., 1990)

50. IR Reflectance Tracking
Tobii 1750 Eye Tracker
HeadMouse®
Extreme

51. Appearance‐Based Tracking
Face Mouse (Perini et al., 2006)
Camera Mouse (Gips et al., 2000)
Clicks through sound/switch
Facial Mouse (Granollers et al., 2006)

52. Motion and Gesture
Tilt Sensing (Chen et al., 2001)
Intelligent Sweet Home (Do et al., 2005)
WebColor Detector (Granollers et al., 2006)

53. Ultrasound
(Lukaszewicz, 2003)
HeadMaster Plus
Telephone keypad
(Coyle and Stewart, 1998)
(Ford and Sheredos, 1995)

54. Tracking Interfaces

55. Myographic Interfaces

56. Muscle Contractions
Electric Potencial Difference

57. Surface
EMG

58. (Jeong et al., 2005)
(Tarng et al., 1997)
Intelligent Sweet Home
(Song et al., 2005)
(Park et al., 1999)

59. Myographic Interfaces

60. Brain‐Computer Interfaces

61. Magnetoencephalography (MEG)
Magnetic Ressonance Imaging (fMRI)
Positron Emission Tomography

62. Electroencephalography
inexpensive
ease of acquisition
high temporal
resolution
real‐time
direct correlation
with brain activity

63. Visual Evoked Potentials
(Vidal, 1973)
Brain Response Interface (Sutter, 1992)
P300 Evoked Potentials
(Farwell and Donchin, 1988)
(Wolpaw et al., 2002)
(Hoffman et al., 2007)
Slow Cortical Potentials
Thought Translation Device (Birbaumer et al, 1999)
mu and Beta Rythms
(Wolpaw and McFarland et al, 2004)
(Pfurtscheller et al., 2003, 2006)

64. Brain‐Computer Interfaces

65. Breath Interfaces

66. Sip and Puff Mouse
(Kitto et al., 1994)
Sip and Puff Switch Breath Joystick
(Grigori and Tatiana,2000)
Thermal Plumes
(Michel and Rancour, 2004)
BLUI (Patel and Abowd, 2007)
Breath Dasher (Shorrock et al, 2004)

67. Breath Interfaces

68. Overall Discussion

69. Potential Users

70. Direct Selection Scanning Encoding
Dimensionality and Input Speed

71. Accuracy

72. Ease of use

73. Aesthetics, Hygiene and Acceptance

74. Mobility Adequacy

75. Maturity, Availability and Cost

76. Concluding Remarks
several technologies for
several targets
all groups covered
….but still highly limited

77. TIAGO GUERREIRO
tjvg@immi.inesc.pt