The first goal of this proposal is to develop a haptic stimulator that provides movement and tactile stimulation to all five fingers and the palm. Using this device, we hope to achieve long-term aims: 1) to understand haptic perception by the hand, including object perception, and movement and vibratory pattern perception; and 2) to put this knowledge to practical use in developing effective communication aids for profoundly deaf and deaf-blind individuals. A motivating hypothesis is that haptic perception, involving both kinesthesis and cutaneous receptors, can provide more information than stimulation to cutaneous receptors alone. This hypothesis draws inspiration from the Tadoma method of speech reception by the blind (Reed et al., 1985) and the ability of normal hearing-sighted individuals to identify objects haptically (Klatzky, et al., 1985). In Project I, engineering and software development will continue on a haptic stimulator currently being developed at Gallaudet University (GU). Project II will study speech and non-speech haptic stimuli. In Study GU-1, normal-hearing and deaf adults will participate in speech identification tasks for which haptic stimuli are designed to aid speech perception via lipreading. In Study GU-2, we will begin to examine haptic perceptual dimensions that might convey speech without lipreading. Hearing-sighted and deaf-blind (Usher syndrome) subjects will give paired-comparison similarity judgments for sets of speech and non-speech haptic stimuli for subsequent multidimensional scaling. A learning study, GU-3, will examine perceptual structure, information transmission and categorization of speech and non- speech stimuli. Project III, at Indiana University (IU), will focus on haptic, non-speech pattern perception and the perception of objects. Study IU-1 will provide evaluations to the engineering team for modifications of the haptic stimulator. Study IU-2 will investigate interactions between vibration and movement patterns on two fingers. These experiments will involve normal subjects and musicians with focal dystonia of the hand. Study IU-3 will investigate the transmission of information about object identity via the haptic stimulator. The results of the proposed work will have diverse applications, including speech aids for deaf and deaf-blind individuals, assessment and possibly remediation of focal dystonia of the hand, and remote sensing of objects by the visually handicapped. The remarkable examples of Tadoma and haptic object perception notwithstanding, haptic perception remains perhaps the least studied of the human perceptual systems. The development of haptic stimulator and the information from the proposed studies will open the way to genuinely new understanding of the haptic system and human perceptual capabilities in general.
| Rinker, M A; Craig, J C; Bernstein, L E (1998) Amplitude and period discrimination of haptic stimuli. J Acoust Soc Am 104:453-63 |
