Masking, Information Integration, and Tactile Pattern Perception: A Comparison of the Isolation and Integration Hypotheses

Abstract

Two competing models of the effects of pattern element proximity, masking, and perceptual integration on the discriminability of spatiotemporal vibrotactile patterns are compared. Kirman's 'integration hypothesis' predicts that pattern perception is facilitated by a process of perceptual integration which requires that pattern elements be presented in close spatial and temporal proximity. Conversely, the 'isolation hypothesis' predicts that the strong masking effects which occur when pattern elements are presented in close proximity impede the perception of patterns. Traditional masking studies do not provide a fair test of these two hypothesis because they rely on methods that measure the subject's ability to identify the target when the target is presented in conjunction with the mask, rather than the discriminability of the complex percept resulting from the integration of the target and mask. To account for this, a new procedure was devised where the amount of interelement masking and the discriminability of the pattern as a whole were measured independently as the spatial and temporal separation of the pattern elements were varied. As expected under both hypotheses, masking between pattern elements increased as either the spatial or the temporal separation between them was decreased. The pattern discrimination data also support the isolation hypothesis in that the patterns were discriminated less well with increasing temporal element separation with a similar but nonsignificant trend in the case of spatial separation. It is concluded that this new methodology should be applied to a wider range of tactile pattern processing situations in order to assess the generality of the results obtained.

Remote Tactile Displays for Future Soldiers

“…While acknowledging masking, Mahar and Mackenzie (1993) proposed a tactile "integration hypothesis" that predicts pattern perception is facilitated by a process of temporal sequencing of the individual elements in spatial and temporal proximity. To assess the relative effects, Mahar and Mackenzie (1993) measured the amount of inter-element masking and the discriminability of patterns as a whole by varying the spatial and temporal separation of pattern elements. As expected, masking among pattern elements increased as the spatial or the temporal separation between them was lessened.…”

Vibrotactile pattern isolation/integration

“…Kirman was specifically concerned with the communication of speech information to the skin and, thus, considered how phonemes (the elements) might combine to form higher linguistic units, such as words and sentences. According to Kirman, the focus in communicating information to the skin should shift from trying to devise stimulus conditions that isolate individual elements and preserve their distinctiveness to examining conditions in which these elements could combine and form larger, identifiable perceptual units.Twenty years later, Mahar and Mackenzie (1993), in considering these ideas, framed the issue in terms of two …”

“…Twenty years later, Mahar and Mackenzie (1993), in considering these ideas, framed the issue in terms of two…”

“…Twenty years later, Mahar and Mackenzie (1993), in considering these ideas, framed the issue in terms of two This research was supported by National Institutes of Health, Grant DC00095, National Institute on Deafness and Other Communication Disorders. The author thanks Roger Rhodes for his assistance in these experiments.…”

Processing of sequential tactile patterns: Effects of a neutral stimulus

“…throughtemporal integration (Craig, 1996;Evans, 1987;Evans & Craig, 1986;Mahar & Mackenzie, 1993) in which the target and nontarget patterns form a single composite pattern. This composite representation may make it difficult for the subject to extract the features of the target pattern and identify it.…”