Functional Connectivity Evoked by Orofacial Tactile Perception of Velocity

The cortical representations of orofacial pneumotactile stimulation involve complex neuronal networks, which are still unknown. This study aims to identify the characteristics of functional connectivity (FC) evoked by three different saltatory velocities over the perioral and buccal surface of the lower face using functional magnetic resonance imaging in twenty neurotypical adults. Our results showed a velocity of 25 cm/s evoked stronger connection strength between the right dorsolateral prefrontal cortex and the right thalamus than a velocity of 5 cm/s. The decreased FC between the right secondary somatosensory cortex and right posterior parietal cortex for 5-cm/s velocity versus all three velocities delivered simultaneously (“All ON”) and the increased FC between the right thalamus and bilateral secondary somatosensory cortex for 65 cm/s vs “All ON” indicated that the right secondary somatosensory cortex might play a role in the orofacial tactile perception of velocity. Our results have also shown different patterns of FC for each seed (bilateral primary and secondary somatosensory cortex) at various velocity contrasts (5 vs 25 cm/s, 5 vs 65 cm/s, and 25 vs 65 cm/s). The similarities and differences of FC among three velocities shed light on the neuronal networks encoding the orofacial tactile perception of velocity

HaptiX: Vibrotactile Haptic Feedback for Communication of 3D Directional Cues

In Human-Computer-Interaction, vibrotactile haptic feedback offers the advantage of being independent of any visual perception of the environment. Most importantly, the user's field of view is not obscured by user interface elements, and the visual sense is not unnecessarily strained. This is especially advantageous when the visual channel is already busy, or the visual sense is limited. We developed three design variants based on different vibrotactile illusions to communicate 3D directional cues. In particular, we explored two variants based on the vibrotactile illusion of the cutaneous rabbit and one based on apparent vibrotactile motion. To communicate gradient information, we combined these with pulse-based and intensity-based mapping. A subsequent study showed that the pulse-based variants based on the vibrotactile illusion of the cutaneous rabbit are suitable for communicating both directional and gradient characteristics. The results further show that a representation of 3D directions via vibrations can be effective and beneficial.Comment: CHI EA '23, April 23-28, 2023, Hamburg, German

Brain encoding of saltatory velocity-scaled somatosensory array in glabrous hand among neurotypical adults

Neurons in human somatosensory cortex are somatotopically organized, with sensation from the lower limbs mediated by neurons near the midline of the brain, whereas sensations from the upper body, hands and orofacial surfaces are mediated by neurons located more laterally in a sequential map. Neurons in Brodmann\u27s area (BA) 3b are exquisitely sensitive to tactile stimulation of these skin surfaces. Moreover, the location, velocity and direction of tactile stimuli on the skin\u27s surface are discriminable features of somatosensory processing, however their role in fine motor control and passive detection are poorly understood in health, and as a neurotherapeutic agent in sensorimotor rehabilitation. To better understand the representation and processing of dynamic saltatory tactile arrays in the human somatosensory cortex, high resolution functional magnetic resonance (fMRI) is utilized to delineate neural networks involved in processing these complex somatosensory events to the glabrous surface of the hand. The principal goal of this dissertation is to map the relation between a dynamic saltatory pneumatic stimulus array delivered at 3 different velocities on the glabrous hand and the evoked blood-oxygen level-dependent (BOLD) brain response, hypothesized to involve a network consisting of primary and secondary somatosensory cortices (S1 and S2), insular cortex, posterior parietal cortex (PPC), and cerebellar nuclei. A random-balanced block design with fMRI will be used to record the BOLD response in healthy right-handed adults. Development of precise stimulus velocities, rapid rise-fall transitions, salient amplitude, is expected to optimize the BOLD response. Advisor: Steven M. Barlo

Brain encoding of saltatory velocity-scaled somatosensory array in glabrous hand among neurotypical adults

Neurons in human somatosensory cortex are somatotopically organized, with sensation from the lower limbs mediated by neurons near the midline of the brain, whereas sensations from the upper body, hands and orofacial surfaces are mediated by neurons located more laterally in a sequential map. Neurons in Brodmann\u27s area (BA) 3b are exquisitely sensitive to tactile stimulation of these skin surfaces. Moreover, the location, velocity and direction of tactile stimuli on the skin\u27s surface are discriminable features of somatosensory processing, however their role in fine motor control and passive detection are poorly understood in health, and as a neurotherapeutic agent in sensorimotor rehabilitation. To better understand the representation and processing of dynamic saltatory tactile arrays in the human somatosensory cortex, high resolution functional magnetic resonance (fMRI) is utilized to delineate neural networks involved in processing these complex somatosensory events to the glabrous surface of the hand. The principal goal of this dissertation is to map the relation between a dynamic saltatory pneumatic stimulus array delivered at 3 different velocities on the glabrous hand and the evoked blood-oxygen level-dependent (BOLD) brain response, hypothesized to involve a network consisting of primary and secondary somatosensory cortices (S1 and S2), insular cortex, posterior parietal cortex (PPC), and cerebellar nuclei. A random-balanced block design with fMRI will be used to record the BOLD response in healthy right-handed adults. Development of precise stimulus velocities, rapid rise-fall transitions, salient amplitude, is expected to optimize the BOLD response. Advisor: Steven M. Barlo

Tactile Displays for Pedestrian Navigation

Existing pedestrian navigation systems are mainly visual-based, sometimes with an addition of audio guidance. However, previous research has reported that visual-based navigation systems require a high level of cognitive efforts, contributing to errors and delays. Furthermore, in many situations a person’s visual and auditory channels may be compromised due to environmental factors or may be occupied by other important tasks. Some research has suggested that the tactile sense can effectively be used for interfaces to support navigation tasks. However, many fundamental design and usability issues with pedestrian tactile navigation displays are yet to be investigated. This dissertation investigates human-computer interaction aspects associated with the design of tactile pedestrian navigation systems. More specifically, it addresses the following questions: What may be appropriate forms of wearable devices? What types of spatial information should such systems provide to pedestrians? How do people use spatial information for different navigation purposes? How can we effectively represent such information via tactile stimuli? And how do tactile navigation systems perform? A series of empirical studies was carried out to (1) investigate the effects of tactile signal properties and manipulation on the human perception of spatial data, (2) find out the effective form of wearable displays for navigation tasks, and (3) explore a number of potential tactile representation techniques for spatial data, specifically representing directions and landmarks. Questionnaires and interviews were used to gather information on the use of landmarks amongst people navigating urban environments for different purposes. Analysis of the results of these studies provided implications for the design of tactile pedestrian navigation systems, which we incorporated in a prototype. Finally, field trials were carried out to evaluate the design and address usability issues and performance-related benefits and challenges. The thesis develops an understanding of how to represent spatial information via the tactile channel and provides suggestions for the design and implementation of tactile pedestrian navigation systems. In addition, the thesis classifies the use of various types of landmarks for different navigation purposes. These contributions are developed throughout the thesis building upon an integrated series of empirical studies.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Effects of Visual Locomotion and Tactile Stimuli Duration on the Emotional Dimensions of the Cutaneous Rabbit Illusion

In this study, we assessed the emotional dimensions (valence, arousal, and dominance) of the multimodal visual-cutaneous rabbit effect. Simultaneously to the tactile bursts on the forearm, visual silhouettes of saltatorial animals (rabbit, kangaroo, spider, grasshopper, frog, and flea) were projected on the left arm. Additionally, there were two locomotion conditions: taking-off and landing. The results showed that the valence dimension (happy-unhappy) was only affected by the visual stimuli with no effect of the tactile conditions nor the locomotion phases. Arousal (excited-calm) showed a significant difference for the three tactile conditions with an interaction effect with the locomotion condition. Arousal scores were higher when the taking-off condition was associated with the intermediate duration (24 ms) and when the landing condition was associated with either the shortest duration (12 ms) or the longest duration (48 ms). There was no effect for the dominance dimension. Similar to our previous results, the valence dimension seems to be highly affected by visual information reducing any effect of tactile information, while touch can modulate the arousal dimension. This can be beneficial for designing multimodal interfaces for virtual or augmented reality.acceptedVersionPeer reviewe

ASSESSING THE EMOTIONAL DIMENSIONS OF THE CUTANEOUS-RABBIT EFFECT USING FACES

This research investigated how emotional images affects tactile saltation. More specifically, we combined visual faces with three different emotions: angry, sad and happy with a tactile illusion known as the cutaneous rabbit effect (CRE) that was delivered on participants’ shoulder at different durations. Because some of the faces were political figures, we assessed participant’s political affiliation using Political Typology Quiz. Participants rated their emotional response using the self-assessment manikin (SAM), a three dimensional scale that measures valence, arousal and dominance. For the valence dimension, our results indicate that participants found it less pleasant to see likeable faces sad than any other figure. Data also showed that it was the least pleasant for participants to see a hateful public face when they were angry. Political affiliation and the duration of the CRE both affected the arousal dimension suggesting that liberals seems more concerned by fictional and public figures than political ones while conservatives seems to be more affected by angry faces of political figures when the tactile duration is the longest. Finally, for the dominance dimension, it was found that likeable figures made participants feel more in control of the situation and that dislikeable figures made participants feel controlled

Somatic ABC's: A Theoretical Framework for Designing, Developing and Evaluating the Building Blocks of Touch-Based Information Delivery

abstract: Situations of sensory overload are steadily becoming more frequent as the ubiquity of technology approaches reality--particularly with the advent of socio-communicative smartphone applications, and pervasive, high speed wireless networks. Although the ease of accessing information has improved our communication effectiveness and efficiency, our visual and auditory modalities--those modalities that today's computerized devices and displays largely engage--have become overloaded, creating possibilities for distractions, delays and high cognitive load; which in turn can lead to a loss of situational awareness, increasing chances for life threatening situations such as texting while driving. Surprisingly, alternative modalities for information delivery have seen little exploration. Touch, in particular, is a promising candidate given that it is our largest sensory organ with impressive spatial and temporal acuity. Although some approaches have been proposed for touch-based information delivery, they are not without limitations including high learning curves, limited applicability and/or limited expression. This is largely due to the lack of a versatile, comprehensive design theory--specifically, a theory that addresses the design of touch-based building blocks for expandable, efficient, rich and robust touch languages that are easy to learn and use. Moreover, beyond design, there is a lack of implementation and evaluation theories for such languages. To overcome these limitations, a unified, theoretical framework, inspired by natural, spoken language, is proposed called Somatic ABC's for Articulating (designing), Building (developing) and Confirming (evaluating) touch-based languages. To evaluate the usefulness of Somatic ABC's, its design, implementation and evaluation theories were applied to create communication languages for two very unique application areas: audio described movies and motor learning. These applications were chosen as they presented opportunities for complementing communication by offloading information, typically conveyed visually and/or aurally, to the skin. For both studies, it was found that Somatic ABC's aided the design, development and evaluation of rich somatic languages with distinct and natural communication units.Dissertation/ThesisPh.D. Computer Science 201

Assisting Navigation and Object Selection with Vibrotactile Cues

Our lives have been drastically altered by information technology in the last decades, leading to evolutionary mismatches between human traits and the modern environment. One particular mismatch occurs when visually demanding information technology overloads the perceptual, cognitive or motor capabilities of the human nervous system. This information overload could be partly alleviated by complementing visual interaction with haptics. The primary aim of this thesis was to investigate how to assist movement control with vibrotactile cues. Vibrotactile cues refer to technologymediated vibrotactile signals that notify users of perceptual events, propose users to make decisions, and give users feedback from actions. To explore vibrotactile cues, we carried out five experiments in two contexts of movement control: navigation and object selection. The goal was to find ways to reduce information load in these tasks, thus helping users to accomplish the tasks more effectively. We employed measurements such as reaction times, error rates, and task completion times. We also used subjective rating scales, short interviews, and free-form participant comments to assess the vibrotactile assisted interactive systems. The findings of this thesis can be summarized as follows. First, if the context of movement control allows the use of both feedback and feedforward cues, feedback cues are a reasonable first option. Second, when using vibrotactile feedforward cues, using low-level abstractions and supporting the interaction with other modalities can keep the information load as low as possible. Third, the temple area is a feasible actuation location for vibrotactile cues in movement control, including navigation cues and object selection cues with head turns. However, the usability of the area depends on contextual factors such as spatial congruency, the actuation device, and the pace of the interaction task