Hypervigilance for innocuous tactile stimuli in patients with fibromyalgia: an experimental approach

Background: Hypervigilance, i.e., excessive attention, is often invoked as a potential explanation for the observation that many individuals with fibromyalgia show a heightened sensitivity to stimulation in various sensory modalities, such as touch and hearing. Compelling evidence for this assumption is, however, lacking. The aim of the present study was to investigate the presence of somatosensory hypervigilance in patients with fibromyalgia. Methods: Fibromyalgia patients (n=41) and a matched control group (n=40) performed a tactile change detection task in which they had to detect whether there was a change between two consecutively presented patterns of tactile stimuli presented to various body locations. The task was performed under two conditions: in the unpredictable condition, tactile changes occurred equally often at all possible body locations; in the predictable condition, the majority of tactile changes occurred at one specific body location. Results: It was hypothesized that the fibromyalgia group would show better tactile change detection in the unpredictable condition and when changes ocurred at unexpected locations in the predictable condition. The results did not support this hypothesis. In neither condition was the fibromyalgia group better than the control group in detecting tactile changes. Conclusions: No evidence was found to support the claim that patients with fibromyalgia display somatosensory hypervigilance. This finding challenges the idea of hypervigilance as a static feature of fibromyalgia and urges for a more dynamic view in which hypervigilance emerges in situations when bodily threat is experienced

Detection of tactile change detection on a bodily location where pain is expected

As it is adaptive to accurately detect and localize bodily threats, it has been proposed that the brain prioritizes somatosensory input at body locations where pain is expected. To test this proposition, the detection of tactile changes on a body location was investigated to assess whether detection was facilitated by threat of pain. Healthy participants (N = 47) indicated whether two consecutive patterns of three tactile stimuli were the same or not. Stimuli could be administered at eight possible locations. In half of the trials, the same pattern was presented twice. In the other half, one stimulus location was different between the two displays. To induce bodily threat, a painful stimulus was occasionally administered to the non-dominant lower arm. Mean accuracy of tactile change detection as a function of location was analyzed using repeated-measures analysis of variance (ANOVA). Tactile changes on the threatened arm (i.e., when a tactile stimulus emerged at or disappeared from that arm), both at the exact pain location (lower arm) and at the other location (upper arm), were better detected than tactile changes on other limbs

Investigating Tactile Displays to Support Anesthesia Providers in the Operating Room

There has been a growing interest in using the tactile modality to offload the often overburdened visual and auditory channels. Although the promise and merit of using the tactile channel has been demonstrated in various work domains, more work is needed to understand perceptual limitations like change blindness. Change blindness refers to the failure in detecting expected visual changes (both small and large) within a scene or on a display when these changes coincide with a visual transient (i.e., a brief disruption in visual continuity). While the majority of work on change blindness has been conducted with vision, there is evidence it affects the tactile modality as well. The goal of this study was to examine how movement and tactile cue complexity affect the ability to detect tactile changes. The findings show that the ability to detect tactile changes is affected by movement as walking resulted in worse change detection rates compared to sitting. The findings also demonstrated that higher complexity cues had worse change detection rates compared to lower complexity cues. Overall, this work adds to the knowledge base of tactile perception and can be applied to multiple work domains such as anesthesiology to inform the design of tactile displays

No evidence for threat-induced spatial prioritization of somatosensory stimulation during pain control using a synchrony judgment paradigm

Topical research efforts on attention to pain often take a critical look at the modulatory role of top-down factors. For instance, it has been shown that the fearful expectation of pain at a location of the body directs attention towards that body part. In addition, motivated attempts to control this pain were found to modulate this prioritization effect. Such studies have often used a temporal order judgment task, requiring participants to judge the order in which two stimuli are presented by indicating which one they perceived first. As this constitutes a forced-choice response format, such studies may be subject to response bias. The aim of the current study was to address this concern. We used a ternary synchrony judgment paradigm, in which participants judged the order in which two somatosensory stimuli occurred. Critically, participants now also had the option to give a `simultaneous' response when they did not perceive a difference. This way we eliminated the need for guessing, and thus reduced the risk of response bias. One location was threatened with the possibility of pain in half of the trials, as predicted by an auditory cue. Additionally, half of the participants (pain control group) were encouraged to avoid pain stimuli by executing a quick button press. The other half (comparison group) performed a similar action, albeit unrelated to the occurrence of pain. Our data did not support threat-induced spatial prioritization, nor did we find evidence that pain control attempts influenced attention in any way

Tactile and Crossmodal Change Blindness and its Implications for Display Design.

Data overload, especially in the visual channel, and associated breakdowns in monitoring already represent a major challenge in data-rich environments. One promising means of overcoming data overload is through the introduction of multimodal displays, i.e., displays which distribute information across various sensory channels (including vision, audition, and touch). This approach has been shown to be effective in offloading the overburdened visual channel and thus reduce data overload. However, the effectiveness of these displays may be compromised if their design does not take into consideration limitations of human perception and cognition. One important question is the extent to which the tactile modality is susceptible to change blindness. Change blindness refers to the failure to detect even large and expected changes when these changes coincide with a “transient” stimulus. To date, the phenomenon has been studied primarily in vision, but there is limited empirical evidence that the tactile modality may also be subject to change blindness. If confirmed, this raises concerns about the robustness of multimodal displays and their use. A series of research activities described in this dissertation sought to answer the following questions: (1) to what extent, and under what circumstances, is the sense of touch susceptible to change blindness, (2) does change blindness occur crossmodally between vision and touch, and (3) how effective are three different display types for overcoming these phenomena. The effect of transient type, transient duration, and task demands were also investigated in the context of Unmanned Aerial Vehicle (UAV) control, the selected domain of application. The findings confirmed the occurrence of intramodal tactile change blindness, but not crossmodal change blindness. Subsequently, three countermeasures to intramodal tactile change blindness were developed and evaluated. The design of these countermeasures focused on supporting four of the five steps required for change detection and was found to significantly improve performance compared to when there was no countermeasure in place. Overall, this research adds to the knowledge base in multimodal and redundant information processing and can inform the design of multimodal displays not only for UAV control, but also other complex, data-rich domains.PhDIndustrial & Operations EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/108870/1/salu_1.pd

Haptics and its effect on consumers' intentions using neuroscientific methods: Literature review

The haptic properties of a product have mostly been underestimated with most studies focusing on visual aspects of objects. Nonetheless, in the last years, it has been found that tactile stimuli are in some cases even more important than the visual ones. However, the traditional paper-based surveys cannot fully and objectively examine their effects on consumers. Therefore, neuroscientific methods, which overcome these obstacles, are becoming more used but there is still only a small number of studies focusing on the effect of haptics in marketing. Using the keywords haptics, tactile input, EEG, fMRI and tactile, seven relevant studies have been found and used in this literature review, out of which four have used EEG and three fMRI. Thus, the main objective of this paper is to review the research that has been already conducted and to identify the areas in which further research should be made and the neuroscientific methods which could be used.O