Influences of the edge radius of curvature of tactile dots and bars on their Discriminability

Tactile dots and bars serve as tactile landmarks so that people with visual impairment can use same consumer products as those used by sighted people. However, reliable age-related data on the appropriate sizes and the shapes was not necessarily available. The purpose of this study is to evaluate influences of edge radius of curvature of tactile dots and bars on their discriminability in younger and older people to determine the appropriate size of tactile bars (as distinguished from tactile dots). Sighted younger and older participants tactually discriminated the tactile dots and bars presented individually, in random order, by a two-alternative forced-choice task. The results showed that both participants discriminated tactile bars from tactile dots faster and more accurately as the dimensional difference between bar length and width increased, regardless of conditions of edge radius of curvature. Therefore, longer dimensional difference between width and length of tactile bars is an important factor to discriminate tactile bars correctly. On the other hand, tactile dots with a larger edge radius of curvature have higher discriminability than tactile dots with a smaller edge radius of curvature in the case of dots of identical height.     

Influences of tactile-dot height and tip radius of curvature on the operational performance of cellular phones

Tactile dots located on operation keys of consumer products such as cellular phones contribute to improving accessibility for older people and people with visual impairment. The Japanese Standards Association (2000) and the International Organization for Standardization (2011) standardized tactile dots. However, reliable data on the appropriate sizes and the shapes was not necessarily available. The purpose of this study is to evaluate influences of the height (0.1, 0.3, 0.55, and 0.75 mm) and the tip radius of curvature (0.1, 0.3, 0.5, 0.7, and 0.9 mm) of tactile dots on the operational performance of cellular phones in younger and older people. Sighted younger and older participants, whose hand was covered by a curtain, operated cellular phones with a tactile dot on its key 5 and without a tactile dot. As the result, both participants performed better at a particular height with larger tip radius of curvature. Furthermore, older participants operated better at high dots like 0.55-0.75 mm. In contrast, younger participants performed better at 0.3 mm and relatively poorly at 0.1 mm and 0.75 mm. Thus, comparatively high tactile dots are useful for improving the accessibility of products for the older and there is an appropriate height range for the younger.     

Comparison of two human-machine-interfaces for cooperative maneuver-based driving

In the project "Conduct-by-Wire" which is founded by the German Research Foundation (DFG) cooperative maneuver based driving is examined. In this paper two different input devices (gesture recognition and tactile touch display) are compared in a simulator study with 29 participants. It shows that the major advantage of the gesture recognition is that there is no need for the driver to take his gaze off the road. In contrast, the number of gazes at the tactile touch display is significantly higher. The major advantage of the tactile touch display is that no input errors occurred during the test drives. Conversely, the gesture recognition was significantly worse. Nevertheless, further work is needed to decide which input device is the best.     

Evidence of tactile arm stepping in newborns and its responsiveness to optic flows specifying self-translation

Although the arms participate in many forms of human locomotion, we know very little about when arm movements emerge during locomotor development. Here we investigated whether newborns would make tactile arm stepping movements when we supported them almost horizontally so their hands touched a surface and blocked their leg movements. Building off prior work showing that newborns make more crawling and air stepping leg movements when exposed to optic flows specifying forward and backward self-translation, we also examined whether newborns would make more tactile arm steps when exposed to forward and backward optic flows compared to a random optic flow that did not specify translation. We found that newborns can perform arm stepping and produce a significantly higher number of tactile arm steps in the optic flow condition specifying backward translation than in the random optic flow condition. Both translating optic flow conditions had significantly higher numbers of alternating arm steps than the random optic flow condition. These findings show that tactile arm stepping exists at birth and that optic flows can facilitate their production, similar to leg stepping. We argue that these results further support the idea that a quadrupedal organization underlies early upright stepping.     

Influence of Maternal Social Communication on Ticklishness in Infants: A Comparison With Being Stroked

The tickle sensation is considered to arise from physiological and social factors. Previous research reports that although infants laugh in response to tactile stimulation in first 6 months of life, they cease laughing to this stimulation as they grow. Because older children often appear to laugh in response to tickling, the current study focused on relationships between infants’ response to tickling and social factors as they grow. Specifically, we examined effects of different maternal social interactions on infants’ reactions to tickling vs. stroking tactile stimulations. Results showed that a tickle stimulus, together with maternal communications, elicits positive reactions in infants. In contrast, a noncommunicative mother and stroking tends to elicit from the child a neutral response, whereas the combination of a noncommunicative mother with tickling evokes negative reactions in infants. These findings suggest that maternal social communication affects infants’ reactions to touch. In addition, the combination of tactile and social stimulations elicits laughter in infants over 6 months of age.     

Emotion Regulation Via Maternal Touch

The study of emotion elicitation in the caregiver‐infant dyad has focused almost exclusively on the facial and vocal channels, whereas little attention has been given to the contribution of the tactile channel. This study was undertaken to investigate the effects of touch on infants' emotions. During the time that objects were presented to the dyad, mothers provided tactile stimulation to their 12‐month‐old infants by either (a) tensing their fingers around the infants' abdomen while abruptly inhaling, (b) relaxing their grip around the infants' abdomen, or (c) not providing additional tactile stimulation (control condition). The results revealed that infants in the first condition (a) touched the objects less and waited longer to touch the objects while displaying more negative emotional displays compared to infants in the control condition. However, no apparent differences were found between infants in the second condition (b) and the control condition. The results suggest that infants' emotions may be elicited by specific parameters of touch.     

Development of Tactile Responses in Human Preterm and Full‐Term Infants From 30 to 40 Weeks Postconceptional Age

Maturation of tactile sensitivity prior to term was examined in 36 preterm and 13 full‐term infants using a fixed‐trial, habituation procedure. Each infant was presented with a series of 8 habituation (arm stroke), 2 novel (arm lift), and 2 recovery (arm stroke) stimulus trials while heart rate and body movements were recorded. Maturation was observed with a gradual increase in the magnitude of the stimulus‐elicited cardiac acceleration and cardiac‐movement coupling from 30 to 40 weeks postconceptional age. The majority of infants displayed habituation—an excitatory response (heart rate acceleration and body movement)—to the initial presentation of a tactile stimulus, response decline with repeated stimulations, and renewed response to a novel stimulus. A substantial number of infants (40%) failed to respond initially to the tactile stimulus, increased responding over several stimulus presentations, and failed to discriminate the presentation of a novel stimulus. We speculate that these differences in response patterns observed over all ages represent individual difference in the perception of stimulus intensity.     

Analgesia produced in women by genital self-stimulation

This study investigated the relative effectiveness of specific genital regional self-stimulation in elevating pain thresholds. Anecdotal reports in humans suggest that sexual activity and orgasm decrease a wide variety of human responses to pain and touch, but the phenomenon has not been evaluated objectively. Two types of self-stimulation, pressure and pleasurable, were applied by 10 women to the anterior vaginal wall, the posterior vaginal wall, and the clitoris. Significant increases in pain thresholds but not tactile thresholds occurred when pressure stimulation was applied to the anterior wall of the vagina or when "pleasurable" self-stimulation was applied to any of the three areas. Tactile thresholds were not significantly affected by any genital stimulation condition. However, there was a significant increase in tactile threshold but not pain thresholds in the distraction control condition. On the basis of these findings, we conclude that (a) a sensation of pleasure evoked by genital stimulation can elevate pain thresholds, (b) these pleasurable stimuli were not general "distractants" because they elevated pain thresholds but not tactile thresholds differentially, and (c) genital pleasurable stimuli activate an analgesic process that is distinct from a distraction process.     

Exploring developmental changes in infant anticipation and perceptual processing: EEG responses to tactile stimulation

There is an increasing interest in alpha-range rhythms in the electroencephalogram (EEG) in relation to perceptual and attentional processes. The infant mu rhythm has been extensively studied in the context of linkages between action observation and action production in infancy, but less is known about the mu rhythm in relation to cross-modal processes involving somatosensation. We investigated differences in mu responses to cued vibrotactile stimulation of the hand in two age groups of infants: From 6 to 7 months and 13 to 14 months. We were also interested in anticipatory neural responses in the alpha frequency range prior to tactile stimulation. Tactile stimulation of infants’ left or right hand was preceded by an audiovisual cue signaling which hand would be stimulated. In response to the tactile stimulus, infants demonstrated significant mu desynchronization over the central areas contralateral to the hand stimulated, with higher mu peak frequency and greater contralateral mu desynchronization for older infants. Prior to the tactile stimulus, both age groups showed significant bilateral alpha desynchronization over frontocentral sites, which may be indicative of generalized anticipation of an upcoming stimulus. The findings highlight the potential of examining the sensorimotor mu rhythm in the context of infant attentional development.     

Analgesia produced in women by genital self‐stimulation

This study investigated the relative effectiveness of specific genital regional self‐stimulation in elevating pain thresholds. Anecdotal reports in humans suggest that sexual activity and orgasm decrease a wide variety of human responses to pain and touch, but the phenomenon has not been evaluated objectively. Two types of self‐stimulation, pressure and pleasurable, were applied by 10 women to the anterior vaginal wall, the posterior vaginal wall, and the clitoris. Significant increases in pain thresholds but not tactile thresholds occurred when pressure stimulation was applied to the anterior wall of the vagina or when “pleasurable” self‐stimulation was applied to any of the three areas. Tactile thresholds were not significantly affected by any genital stimulation condition. However, there was a significant increase in tactile threshold but not pain thresholds in the distraction control condition. On the basis of these findings, we conclude that (a) a sensation of pleasure evoked by genital stimulation can elevate pain thresholds, (b) these pleasurable stimuli were not general “distractants” because they elevated pain thresholds but not tactile thresholds differentially, and (c) genital pleasurable stimuli activate an analgesic process that is distinct from a distraction process.     

Creating Tactile Space during a University Extension Field Day Event: The Case of a Sustainable Agriculture Innovation

Drawing on the concept of “tactile space,” we evaluate the experiential learning environment of a university extension field day event focused on a sustainable agriculture innovation: biodegradable plastic mulch. Introduced by sociologist Michael Carolan, “tactile spaces” are sensuously rich learning environments where participants interact with each other and the environment in an “embodied” and “embedded” manner leading to long‐lasting attitudinal and behavioral change. In our study, farmers, extension professionals, crop consultants, and mulch manufacturers participated in a field day event designed to provide both embodied and embedded experiences in an effort to stimulate interest in biodegradable plastic mulch, an economically and environmentally sustainable alternative to polyethylene mulch. Field day participants engaged in hands‐on demonstrations preceded and followed by focus group sessions. Enhancing the learning environment in these ways improved the success of the field day event by encouraging practice‐based forms of learning, which supplemented and reinforced the claims made about biodegradable plastic mulch. However, the tactile space could have been enriched by providing more opportunities for participants to become embedded within the environment, and by adding elements to overcome the temporal limitations of the field day event. This research contributes to the broader literature on participatory research and extension.     

Establishing auditory-tactile-visual equivalence classes in children with autism and developmental delays

The Analysis of Verbal Behavior - The current study sought to evaluate the efficacy of a stimulus equivalence training procedure in establishing auditory–tactile–visual stimulus classes...     

International Patterns of Interpersonal Tactile Communication: A Field Study

An awareness of how touch is employed in communicative interactions among peoples of different nations can be a critical requisite to effective inter-cultural communication. This study examined cross-sex, interpersonal, public touch to determine whether (1) the number of body areas touched varied between members of different societies; (2) the type of relationship between dyadic partners influenced tactile behavior; and (3) the amount of total body areas touched for each society correlated with latitude of origin. Variation in interpersonal touch as a function of nationality was confirmed. Results also confirmed that touch between dyads from an international sample was affected by type of relationship. Correspondence in the occurrence of tactile behavior among dyads from similar latitudes of origin was not confirmed. Findings call into question the designation of Northern European and U.S. cultures as non-contact.     

People with sight impairment in the world of visual arts: does it make any sense?

Abstract

The article describes an educational and artistic project in Poland where individuals with sight impairments could learn more about visual arts through guided city tours around their greatest monuments, appreciation of art pieces and meetings with artists. During workshops, they could test their own artistic skills by creating tactile drawings, pottery sculptures, photographs and tactile picture book. The effects of their attempts were presented in a temporary exhibition in the contemporary art gallery (with an associated educational program). The exhibition was a significant experience both for the artists with visual impairments and the visitors. Through analysis of the structure and content of the artworks, the gallery visitors could understand more about the situation of people with sight impairments as they struggle with everyday tasks and how creative they are.     

The TacVi technique: a tactile-visual method for exploring the self-concept of preschool children

Efforts to investigate preschool children's self-concept have not been notably successful, despite historical interest in the developmental aspects of the self. The authors offer the TacVi technique as a tactile and visual method for exploring young children's perceptions of themselves in comparison with their peers.     

Multimodal urgency coding: auditory, visual, and tactile parameters and their impact on perceived urgency

Through a series of investigations involving different levels of contextual fidelity we developed scales of perceived urgency for several dimensions of the auditory, visual, and tactile modalities. Psychophysical ratings of perceived urgency, annoyance, and acceptability as well as behavioral responses to signals in each modality were obtained and analyzed using Steven's Power Law to allow comparison across modalities. Obtained results and their implications for use as in-vehicle alerts and warnings are discussed.     

The Organization of Wariness of Heights in Experienced Crawlers

Most infants with more than 6 weeks of crawling experience completely avoid the deep side of a visual cliff ( Campos, Bertenthal, & Kermoian, 1992 ; Gibson & Walk, 1960 ). However, some experienced crawlers do move onto the transparent surface suspended several feet above the ground. An important question is whether these nonavoiders lack wariness of heights or whether they have a qualitatively different way of showing their wariness than do avoiders of the deep side. The current study addressed this question by measuring heart rate (HR) acceleration upon being lowered on the deep and shallow sides of the visual cliff, latency to crawl toward the mother, and tactile exploration of the cliff surface. Nonavoiders and avoiders had indistinguishable patterns of HR acceleration, showing greater HR acceleration when lowered onto the deep than when lowered onto the shallow side of the cliff. Nonavoiders also showed more tactile exploration and longer latencies than did a comparable group of infants tested on the shallow side. This study illustrates how the same emotion, wariness of heights, can be shown by qualitatively different behaviors, all serving the same function of protecting the individual from falling over a drop‐off.     

Tactile relationships in the subway as affected by racial,sexual, and crowded seating situations

Observations of touching behavior were made on New York City's IRT subway line to determine whether homogeneous behavioral patterns exist in the subway. Direct observations of race, sex, and crowding on subway car benches were made. These factors were coded as variables that might affect touching among strangers. The data indicated the presence of tactile avoidance behavior in crowded situations, but statistical significance was achieved only in the case of racial and sexual heterogeneous relationships. The data support Leichty's hypothesis (1975) concerning the existence and operation of universes of touch. The demonstration of patterned interaction challenges the view of subways as environments of heterogeniety.     

Newborn Body Perception: Sensitivity to Spatial Congruency

Studies on adults have demonstrated that the perception our own body can be manipulated by varying both temporal and spatial properties of multisensory information. While human newborns are capable of detecting the temporal synchrony of visuo‐tactile body‐related cues, it remains unknown whether they also utilise spatial information for body perception. Twenty newborns were presented with a video of an infant's face touched with a paintbrush, while their own face was touched either in the spatially congruent, or an incongruent, location. We found that newborns show a visual preference for spatially congruent synchronous events, supporting the view that newborns have a rudimentary sense of their own body.