Vibrotactile pattern discrimination and communality at several body sites

Abstract

In a series of experiments, the effects of spatial layout on vibrotactile pattern perception were explored by testing the ability to discriminate between two sequentially presented patterns that share active elements in the same spatial locations. Two-dimensional displays were used in order to examine the functional relationship between discrimination performance and pattern communality, defined as the sharing elements, on different body sites. Accuracy of discrimination judgments was inversely proportional to communality, regardless of the number of pattern elements. For compact arrays fitted to the finger, palm, and thigh, the effects of communality appeared equivalent. The similarity between finger and thigh functions is remarkable, considering the dramatic differences between these sites in receptor components and structure. Whenthese data were compared with those from arrays with distributed contactors, performance was substantially better with well-separated pattern elements, Such findings help to explicate how information from apposed patterns can best be delivered to the skin through tactile communication systems,

The generation of vibrotactile patterns on a linear array: Influences of body site, time, and presentation mode

“…In the few studies that have examined these issues, both differences and commonalities in performance have been found among such sites as the finger, forearm, and thigh when the perception of tactile extent (Cholewiak, 1986(Cholewiak, , 1999, pattern "communality" (Cholewiak & Collins, 1995), pattern identification and discrimination (Cholewiak & Craig, 1984), and cutaneous saltation (Geldard & Sherrick, 1983) were measured, using vibrotactile arrays. In only three studies that we are aware of (Cholewiak & Collins, 1988;Cholewiak & Craig, 1984;Engelmann & Rosov, 1975) have the perceptions of the same set of patterns been examined on several body sites to evaluate whether the percepts are isomorphic.…”

Haptic pen

“…This data, shown in Figure 2, clearly show similarity both in terms of duration and overall profile shape when compared to an actual retractable pen and a stiff mechanical button. Many of the residual differences are in the 1kHz range and approach the limits of human perception [14]. This shows that our simple solenoid-based design is capable of producing sensations similar to familiar mechanical switches.…”

A broadband tactile array on the fingertip

“…The stimulator array described below is intended to meet this need, and the two experiments described below demonstrate the array's potential for obtaining psychophysics data in the research area of interest. ͓This research area can be considered as either ͑i͒ an extension of established single-contactor, variable-frequency techniques into the multiple-contactor context; ͑ii͒ an extension of previous studies using arrays such as the Optacon into investigations involving more flexible control of stimulus waveform; or ͑iii͒ an extension of previous neurophysiological studies on spatiotemporal perception into the area of psychophysics.͔ Both experiments involve simultaneous masking techniques, in contrast to previous array-based studies of tactile masking ͑for example, Craig and Xu, 1990;Cholewiak and Collins, 1995;Horner, 1997Horner, , 2000Craig, 2000͒ which have concentrated on sequential presentation of target and masker because of the limitations of previous stimulator hardware. ͓For a study involving simultaneous masking, see Weisenberger and Craig ͑1982͒.͔ In addition, both experiments involve discrimination of direction of movement on the array.…”