Experiments have been carried out to investigate the information transfer available via a single vibrator on the fingertip. In a first experiment, for stimuli with durations 80 to 320 ms, discrimination of a one-octave step change in frequency at the halfway point was investigated. Results were similar for three stimulus types—sinewave, monophasic pulse and tetraphasic pulse—suggesting temporal cues are more important than spectral cues in this task. In a second experiment, subjects were required to perceive changes in a sequence of stimulus elements. A presentation rate of 6.25 elements s−1 was found to give better results than a rate of 12.5 elements s−1. In the former case, the potential information transfer per element was estimated to be approximately 1.0 bits, corresponding to an information transfer rate of around 6 bits s−1. Implications for the design of a tactile aid to lipreading are discussed.

1.
Bernstein, L. E. (1992). “The evaluation of tactile aids,” in Tactile Aids for the Hearing Impaired, edited by I. R. Summers (Whurr, London), pp. 167–186.
2.
Bernstein
,
L. E.
,
Schechter
,
M. B.
, and
Goldstein
,
M. H.
(
1986
). “
Child and adult vibrotactile thresholds for sinusoidal and pulsatile stimuli
,”
J. Acoust. Soc. Am.
80
,
118
123
.
3.
Bernstein
,
L. E.
,
Eberhardt
,
S. P.
, and
Demorest
,
M. E.
(
1989
). “
Single-channel vibrotactile supplements to visual perception of intonation and stress
,”
J. Acoust. Soc. Am.
85
,
397
405
.
4.
Blamey
,
P. J.
, and
Clark
,
G. M.
(
1985
). “
A wearable multiple-electrode electrotactile speech processor for the profoundly deaf
,”
J. Acoust. Soc. Am.
77
,
1619
1620
.
5.
Blamey
,
P. J.
, and
Clark
,
G. M.
(
1987
). “
Psychophysical studies relevant to the design of a digital electrotactile speech processor
,”
J. Acoust. Soc. Am.
82
,
116
125
.
6.
Blamey
,
P. J.
,
Alcantara
,
J. I.
,
Cowan
,
R. S. C.
,
Galvin
,
K. L.
,
Sarant
,
J. Z.
, and
Clark
,
G. M.
(
1990
). “
Perception of amplitude variations of pulsatile electrotactile stimuli
,”
J. Acoust. Soc. Am.
88
,
1765
1772
.
7.
Bolanowski
, Jr.,
S. J.
,
Gescheider
,
G. A.
,
Verrillo
,
R. T.
, and
Checkowsky
,
C. M.
(
1988
). “
Four channels mediate the mechanical aspects of touch
,”
J. Acoust. Soc. Am.
84
,
1680
1694
.
8.
Braida
,
L. D.
, and
Durlach
,
N. I.
(
1972
). “
Intensity perception. II. Resolution in one-interval paradigms
,”
J. Acoust. Soc. Am.
51
,
483
502
.
9.
Cornett, R. O. (1967). “Cued speech,” Am. Ann. Deaf 112, 3–13.
10.
Craven
,
B. J.
(
1992
). “
A table of d for M-alternative odd-man-out forced-choice procedures
,”
Percept. Psychophys.
51
,
379
385
.
11.
Crystal
,
T. H.
, and
House
,
A. S.
(
1988
). “
Segmental durations in connected-speech signals—Current results
,”
J. Acoust. Soc. Am.
83
,
1553
1573
.
12.
Ebrahimi
,
D.
, and
Kunov
,
H.
(
1991
). “
Peripheral vision lipreading aid
,”
IEEE Trans. Biomed. Eng.
38
,
944
952
.
13.
Formby
,
C.
,
Morgan
,
L. N.
,
Forrest
,
T. G.
, and
Raney
,
J. J.
(
1992
). “
The role of frequency selectivity in measures of auditory and vibrotactile temporal resolution
,”
J. Acoust. Soc. Am.
91
,
293
305
.
14.
Kokjer
,
K. J.
(
1987
). “
The information capacity of the human fingertip
,”
IEEE Trans. Syst. Man Cybern.
17
,
100
102
.
15.
Lamoré
,
P. J. J.
, and
Keemink
,
C. J.
(
1988
). “
Evidence for different types of mechanoreceptors from measurements of the psychophysical threshold for vibrations under different stimulation conditions
,”
J. Acoust. Soc. Am.
83
,
2339
2351
.
16.
Lechelt, E. C. (1975). “Temporal numerosity discrimination: Intermodal comparisons revisited,” Br. J. Psychol. 66, 101–108.
17.
Lechelt, E. C. (1980). “Lateral differences and shifts as a function of tactile temporal pattern complexity: Implications for differential processing strategies of the cerebral hemispheres,” Psychol. Res. 41, 319–333.
18.
Miller
,
G. A.
, and
Nicely
,
P. E.
(
1955
). “
An analysis of perceptual confusions among English consonants
,”
J. Acoust. Soc. Am.
27
,
338
352
.
19.
Rabinowitz
,
W. M.
,
Houtsma
,
A. J. M.
,
Durlach
,
N. I.
, and
Delhorne
,
L. A.
(
1987
). “
Multidimensional tactile displays: Identification of vibratory intensity, frequency and contactor area
,”
J. Acoust. Soc. Am.
82
,
1243
1252
.
20.
Reed, C. M., Durlach, N. I., and Delhorne, L. A. (1992a). “The tactual reception of speech, fingerspelling and sign language by the deaf-blind,” SID-92 Digest, 102–105.
21.
Reed, C. M., Durlach, N. I., and Delhorne, L. A. (1992b). “Natural methods of tactual communication,” in Tactile Aids for the Hearing Impaired, edited by I. R. Summers (Whurr, London), pp. 218–230.
22.
Rothenberg
,
M.
,
Verrillo
,
R. T.
,
Zahorian
,
S. A.
,
Brachman
,
M. L.
, and
Bolanowski
, Jr.,
S. J.
(
1977
). “
Vibrotactile frequency for encoding a speech parameter
,”
J. Acoust. Soc. Am.
62
,
1003
1012
.
23.
Sherrick
,
C. E.
(
1985
). “
A scale rate for tactual vibration
,”
J. Acoust. Soc. Am.
78
,
78
83
.
24.
Srinivasan, M. A. (1995). “Haptic interfaces,” in Virtual Reality, Scientific and Technical Challenges, edited by N. I. Durlach and A. S. Mavor (National Academy Press, Washington, DC), pp. 161–187.
25.
Summers, I. R. (1992). “Signal processing strategies for single-channel systems,” in Tactile Aids for the Hearing Impaired, edited by I. R. Summers (Whurr, London), pp. 110–127.
26.
Summers, I. R., and Farr, J. (1989). “Development of a single-channel tactile aid for the profoundly deaf,” Proc. Eurospeech ’89, Paris, 2, 706–709.
27.
Summers
,
I. R.
,
Dixon
,
P. R.
,
Cooper
,
P. G.
,
Gratton
,
D. A.
,
Brown
,
B. H.
, and
Stevens
,
J. C.
(
1994
). “
Vibrotactile and electrotactile perception of time-varying pulse trains
,”
J. Acoust. Soc. Am.
95
,
1548
1558
.
28.
Summers, I. R., Milnes, P., Stevens, J. C., and Cooper, P. G. (1996). “Coding of acoustic features for a single-channel tactile aid,” Br. J. Audiol. 30, 238–248.
29.
Tan, H. Z. (1996). “Information transmission with a multi-finger tactual display,” unpublished Ph.D. thesis, Massachusetts Institute of Technology.
30.
Tan, H. Z. (1997). Personal communication.
31.
Tan, H. Z., Durlach, N. I., Rabinowitz, W. M., and Reed, C. M. (1996). “Information transmission with a multi-finger tactual display,” Proc. ISAC-96, Sint-Michielsgestel, 37–40.
32.
Uchanski, R. M., Delhorne, L. A., Dix, A. K., Braida, L. D., Reed, C. M., and Durlach, N. I. (1994). “Automatic speech recognition to aid the hearing impaired: Prospects for the automatic generation of cued speech,” J. Rehab. Res. Dev. 31, 20–41.
33.
Upton, H. W. (1968). “Wearable eyeglass speechreading aid,” Am. Ann. Deaf 113, 222–229.
34.
Verrillo, R. T., and Gescheider, G. A. (1992). “Perception via the sense of touch,” in Tactile Aids for the Hearing Impaired, edited by I. R. Summers (Whurr, London), pp. 1–36.
35.
Verrillo
,
R. T.
,
Fraioli
,
A. J.
, and
Smith
,
R. L.
(
1969
). “
Sensation magnitude of vibrotactile stimuli
,”
Percept. Psychophys.
6
,
366
372
.
36.
Weisenberger
,
J. M.
(
1986
). “
Sensitivity to amplitude-modulated vibrotactile signals
,”
J. Acoust. Soc. Am.
80
,
1707
1715
.
37.
Weisenberger, J. M. (1992). “Communication of the acoustic environment via tactile stimuli,” in Tactile Aids for the Hearing Impaired, edited by I. R. Summers (Whurr, London), pp. 83–109.
38.
Weisenberger
,
J. M.
, and
Russell
,
A. F.
(
1989
). “
Comparison of two single-channel vibrotactile aids for the hearing-impaired
,”
J. Speech Hear. Res.
32
,
83
92
.
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