Tactile Displays

Author(s):  
Kurt A. Kaczmarek ◽  
Paul Bach-Y-Rita

The average adult has approximately 2m2 of skin (Gibson, 1968), about 90% hairy, and remainder smooth or glabrous. Although the glabrous areas are more sensitive than the hairy, both types are highly innervated with sensory receptors and nerves (Sinclair, 1981). Tactile displays have utilized both glabrous and hairy skin, the type selected being relative to the sensory display needs of the various investigators. There are several advantages for selecting the skin as the sensory surface to receive information. (1) It is accessible, extensive in area, richly innervated, and capable of precise discrimination. Further, when the skin of the forehead or trunk is used, the tactile display system does not interfere materially with motor or other sensory functions. (2) The skin shows a number of functional similarities to the retina of the eye in its capacity to mediate information. Large parts of the body surface are relatively flat, and the receptor surfaces of the skin, like the retina, are capable of mediating displays in two spatial dimensions as well as having the potential for temporal integration (summation over time). Thus, there is generally no need for complex topological transformation or for temporal coding of pictorial information for direct presentation onto the accessible areas of the skin, although temporal display factors have been explored with the goal of transmitting spatial information across the skin more quickly than is possible with present systems (Kaczmarek et al., 1984; Bach-y-Rita and Hughes, 1985; Kaczmarek et al., 1985; Loomis and Lederman, 1986). Spatial patterns learned visually can be identified factually, and vice versa (Epstein et al., 1989; Hughes et al., 1990). (3) Certain types of sensory inhibition, including the Mach band phenomenon and other examples of lateral inhibition originally demonstrated for vision, are equally demonstrable in the skin (Bekesy, 1967). (4) Finally, there is evidence that the skin normally functions as an exteroceptor at least in a limited sense: Katz noted that to some extent both vibration and temperature changes can be felt at a distance (Krueger, 1970). For example, a blind person can “feel” the approach of a warm cylinder at three times the distance required by the sighted individual (Krueger, 1970).

Author(s):  
Kylie Gomes ◽  
Scott Betza ◽  
Sara Lu Riggs

Objective To evaluate the effects that movement, cue complexity, and the location of tactile displays on the body have on tactile change detection. Background Tactile displays have been demonstrated as a means to address data overload by offloading the visual and auditory modalities. However, change blindness—the failure to detect changes in a stimulus when changes coincide with another event or disruption in stimulus continuity—has been demonstrated to affect the tactile modality and may be exacerbated during movement. The complexity of tactile cues and locations of tactile displays on the body may also affect the detection of changes in tactile patterns. Limitations to tactile perception need to be examined. Method Twenty-four participants performed a tactile change detection task while sitting, standing, and walking. Tactile cues varied in complexity and included low, medium, and high complexity cues presented to the arm or back. Results Movement adversely affects tactile change detection as hit rates were the highest while sitting, followed by standing and walking. Cue complexity affected tactile change detection: Low complexity cues resulted in higher detection rates compared with medium and high complexity cues. The arms exhibited better change detection performance than the back. Conclusion The design of tactile displays should consider the effect of movement. Cue complexity should be minimized and decisions about the location of a tactile display should take into account body movements to support tactile perception. Application The findings can provide design guidelines to inform tactile display design for data-rich, complex domains.


2021 ◽  
Author(s):  
Ravinderjit Singh ◽  
Hari Bharadwaj

The auditory system has exquisite temporal coding in the periphery which is transformed into a rate-based code in central auditory structures like auditory cortex. However, the cortex is still able to synchronize, albeit at lower modulation rates, to acoustic fluctuations. The perceptual significance of this cortical synchronization is unknown. We estimated physiological synchronization limits of cortex (in humans with electroencephalography) and brainstem neurons (in chinchillas) to dynamic binaural cues using a novel system-identification technique, along with parallel perceptual measurements. We find that cortex can synchronize to dynamic binaural cues up to approximately 10 Hz, which aligns well with our measured limits of perceiving dynamic spatial information and utilizing dynamic binaural cues for spatial unmasking, i.e. measures of binaural sluggishness. We also find the tracking limit for frequency modulation (FM) is similar to the limit for spatial tracking, demonstrating that this sluggish tracking is a more general perceptual limit that can be accounted for by cortical temporal integration limits.


Author(s):  
U. Khompodoeva ◽  
R. Ivanov

The results of researches on the peculiarities of metabolism in the body of horses of Yakut breed in the winter and spring periods under the environments of Central Yakutia have been presented in the article. Physiological experiments on the digestibility of the main nutrients of the feed have been carried out in the winter (February) and spring (April) periods under the environments of the physiological yard in the Yakutsk Scientific and Research Institute of Agriculture named after M. G. Safronov with using the classical method. Five mares and five geldings of Yakut breed have been selected for researches. The average live weight of mares was 378–410 kg, geldings 394–403 kg. The experimental animals had average fatness. It has been found a higher intake of energy and the main nutrients of hay as a mono feed in winter compared to the spring period. At the same time pregnant mares in winter have been consumed 103,8±3,12 MJ of metabolic energy per head/day, which was 27,3 % significantly higher than in the spring period – 75,4±2,18 MJ (P ≥ 0,999). Geldings have been consumed in the experiment 67,70±2,85 MJ, which was by 43,7 % higher than in the spring period – 38,05 ± 4,40 MJ of metabolic energy per head/day (P ≥ 0,999). Experimental animals have been housed in stalls; there was no energy expenditure for movement, so the amount of energy consumed in winter indicates the production of heat in the animal’s body. Pregnant mares per 100 kg of live weight have consumed 31,5±4,11 MJ of metabolic energy or 33,3 % more than in the spring period – 21,0±1,98 MJ; geldings have consumed 27,69±1,12, which was 41,78 % significantly higher than in the spring – 16,12 ± 0,75 MJ (P ≥ 0,999). The high intake of metabolic energy into the body of Yakut horses in winter is explained by the manifestation of adaptive mechanisms that affect the effective metabolism for survival, adapted to frequent changes in weather conditions and sharp temperature changes. The established differences in the biochemical parameters of blood serum of horses of Yakut breed are associated with changes in the consumption and digestibility of basic nutrients and energy, depending on the ambient temperature.


2021 ◽  
Vol 7 (1) ◽  
pp. 540-555
Author(s):  
Hayley L. Mickleburgh ◽  
Liv Nilsson Stutz ◽  
Harry Fokkens

Abstract The reconstruction of past mortuary rituals and practices increasingly incorporates analysis of the taphonomic history of the grave and buried body, using the framework provided by archaeothanatology. Archaeothanatological analysis relies on interpretation of the three-dimensional (3D) relationship of bones within the grave and traditionally depends on elaborate written descriptions and two-dimensional (2D) images of the remains during excavation to capture this spatial information. With the rapid development of inexpensive 3D tools, digital replicas (3D models) are now commonly available to preserve 3D information on human burials during excavation. A procedure developed using a test case to enhance archaeothanatological analysis and improve post-excavation analysis of human burials is described. Beyond preservation of static spatial information, 3D visualization techniques can be used in archaeothanatology to reconstruct the spatial displacement of bones over time, from deposition of the body to excavation of the skeletonized remains. The purpose of the procedure is to produce 3D simulations to visualize and test archaeothanatological hypotheses, thereby augmenting traditional archaeothanatological analysis. We illustrate our approach with the reconstruction of mortuary practices and burial taphonomy of a Bell Beaker burial from the site of Oostwoud-Tuithoorn, West-Frisia, the Netherlands. This case study was selected as the test case because of its relatively complete context information. The test case shows the potential for application of the procedure to older 2D field documentation, even when the amount and detail of documentation is less than ideal.


2012 ◽  
Vol 41 (1) ◽  
pp. 29-71 ◽  
Author(s):  
Terra Edwards

AbstractThis article is concerned with how social actors establish relations between language, the body, and the physical and social environment. The empirical focus is a series of interactions between Deaf-Blind people and tactile signed language interpreters in Seattle, Washington. Many members of the Seattle Deaf-Blind community were born deaf and, due to a genetic condition, lose their vision slowly over the course of many years. Drawing on recent work in language and practice theory, I argue that these relations are established by Deaf-Blind people through processes ofintegrationwhereby continuity between linguistic, embodied, and social elements of a fading visual order are made continuous with corresponding elements in an emerging tactile order. In doing so, I contribute to current attempts in linguistic anthropology to model the means by which embodied, linguistic, and social phenomena crystallize in relational patterns to yield worlds that take on the appearance of concreteness and naturalness. (Classifiers, Deaf-Blind, integration, interpretation, language and embodiment, practice, rhythm, Tactile American Sign Language, tactility)*


1961 ◽  
Vol 38 (2) ◽  
pp. 301-314 ◽  
Author(s):  
BODIL NIELSEN

1. In two species of Lacerta (L. viridis and L. sicula) the effects on respiration of body temperature (changes in metabolic rate) and of CO2 added to the inspired air were studied. 2. Pulmonary ventilation increases when body temperature increases. The increase is brought about by an increase in respiratory frequency. No relationship is found between respiratory depth and temperature. 3. The rise in ventilation is provoked by the needs of metabolism and is not established for temperature regulating purposes (in the temperature interval 10°-35°C). 4. The ventilation per litre O2 consumed has a high numerical value (about 75, compared to about 20 in man). It varies with the body temperature and demonstrates that the inspired air is better utilized at the higher temperatures. 5. Pulmonary ventilation increases with increasing CO2 percentages in the inspired air between o and 3%. At further increases in the CO2 percentage (3-13.5%) it decreases again. 6. At each CO2 percentage the pulmonary ventilation reaches a steady state after some time (10-60 min.) and is then unchanged over prolonged periods (1 hr.). 7. The respiratory frequency in the steady state decreases with increasing CO2 percentages. The respiratory depth in the steady state increases with increasing CO2 percentages. This effect of CO2 breathing is not influenced by a change in body temperature from 20° to 30°C. 8. Respiration is periodically inhibited by CO2 percentages above 4%. This inhibition, causing a Cheyne-Stokes-like respiration, ceases after a certain time, proportional to the CO2 percentage (1 hr. at 8-13% CO2), and respiration becomes regular (steady state). Shift to room air breathing causes an instantaneous increase in frequency to well above the normal value followed by a gradual decrease to normal values. 9. The nature of the CO2 effect on respiratory frequency and respiratory depth is discussed, considering both chemoreceptor and humoral mechanisms.


PEDIATRICS ◽  
1963 ◽  
Vol 32 (4) ◽  
pp. 691-702
Author(s):  
Sid Robinson

The central body temperature of a man rises gradually during the first half hour of a period of work to a higher level and this level is precisely maintained until the work is stopped; body temperature then slowly declines to the usual resting level. During prolonged work the temperature regulatory center in the hypothalamus appears to be reset at a level which is proportional to the intensity of the work and this setting is independent of environmental temperature changes ranging from cold to moderately warm. In hot environments the resistance to heat loss may be so great that all of the increased metabolic heat of work cannot be dissipated and the man's central temperature will rise above the thermostatic setting. If this condition of imbalance is continued long enough heat stroke will ensue. We have found that in a 3 mile race lasting only 14 minutes on a hot summer day a runner's rectal temperature may rise to 41.1°C., with heat stroke imminent. The physiological regulation of body temperature of men in warm environments and during the increased metabolic heat production of work is dependent on sweating to provide evaporative cooling of the skin, and on adjustments of cutaneous blood flow which determine the conductance of heat from the deeper tissues to the skin. The mechanisms of regulating these responses during work are complex and not entirely understood. Recent experiments carried out in this laboratory indicate that during work, sweating may be regulated by reflexes originating from thermal receptors in the veins draining warm blood from the muscles, summated with reflexes from the cutaneous thermal receptors, both acting through the hypothalamic center, the activity of which is increased in proportion to its own temperature. At the beginning of work the demand for blood flow to the muscles results in reflex vasoconstriction in the skin. As the body temperature rises the thermal demand predominates and the cutaneous vessels dilate, increasing heat conductance to the skin. Large increments in cardiac output and compensatory vasoconstriction in the abdominal viscera make these vascular adjustments in work possible without circulatory embarrassment.


Fluids ◽  
2020 ◽  
Vol 5 (2) ◽  
pp. 82
Author(s):  
Kyle W. Leathers ◽  
Brenden T. Michaelis ◽  
Matthew A. Reidenbach

Olfactory systems in animals play a major role in finding food and mates, avoiding predators, and communication. Chemical tracking in odorant plumes has typically been considered a spatial information problem where individuals navigate towards higher concentration. Recent research involving chemosensory neurons in the spiny lobster, Panulirus argus, show they possess rhythmically active or ‘bursting’ olfactory receptor neurons that respond to the intermittency in the odor signal. This suggests a possible, previously unexplored olfactory search strategy that enables lobsters to utilize the temporal variability within a turbulent plume to track the source. This study utilized computational fluid dynamics to simulate the turbulent dispersal of odorants and assess a number of search strategies thought to aid lobsters. These strategies include quantification of concentration magnitude using chemosensory antennules and leg chemosensors, simultaneous sampling of water velocities using antennule mechanosensors, and utilization of antennules to quantify intermittency of the odorant plume. Results show that lobsters can utilize intermittency in the odorant signal to track an odorant plume faster and with greater success in finding the source than utilizing concentration alone. However, the additional use of lobster leg chemosensors reduced search time compared to both antennule intermittency and concentration strategies alone by providing spatially separated odorant sensors along the body.


2001 ◽  
Vol 92 (1) ◽  
pp. 223-233
Author(s):  
D. P. McCabe ◽  
D. I. Ben-Tovim ◽  
M. K. Walker ◽  
D. Pomeroy

Do the mental Images of 3-dimensional objects recreate the depth characteristics of the original objects' This investigation of the characteristics of mental images utilized a novel boundary-detection task that required participants to relate a pair of crosses to the boundary of an image mentally projected onto a computer screen. 48 female participants with body attitudes within expected normal range were asked to image their own body and a familiar object from the front and the side. When the visual mental image was derived purely from long-term memory, accuracy was better than chance for the front (64%) and side (63%) of the body and also for the front (55%) and side (68%) of the familiar nonbody object. This suggests that mental images containing depth and spatial information may be generated from information held in long-term memory. Pictorial exposure to views of the front or side of the objects was used to investigate the representations from which this 3-dimensional shape and size information is derived. The results are discussed in terms of three possible representational formats and argue that a front-view 2½-dimensional representation mediates the transfer of information from long-term memory when depth information about the body is required.


1994 ◽  
Vol 195 (1) ◽  
pp. 345-360 ◽  
Author(s):  
J N Stinner ◽  
D L Newlon ◽  
N Heisler

Previous studies of reptiles and amphibians have shown that changing the body temperature consistently produces transient changes in the respiratory exchange ratio (RE) and, hence, changes in whole-body CO2 stores, and that the extracellular fluid compartment contributes to the temperature-related changes in CO2 stores. The purpose of this study was to determine whether the intracellular fluid compartment contributes to the changes in CO2 stores in undisturbed resting cane toads. Increasing body temperature from 10 to 30 degrees C temporarily elevated RE, and returning body temperature to 10 degrees C temporarily lowered RE. The estimated average change in whole-body CO2 stores associated with the transient changes in RE was 1.0 +/- 0.8 mmol kg-1 (+/- S.D., N = 6). Plasma [CO2] and, thus, extracellular fluid [CO2], were unaffected by the temperature change. Plasma calcium levels were also unaffected, so that bone CO2 stores did not contribute to changes in whole-body CO2 stores. Intracellular [CO2] was determined for the lung, oesophagus, stomach, small intestine, liver, ventricle, red blood cells, skin and 14 skeletal muscles. [CO2] was significantly lower (P < 0.05) at higher temperature in 10 of these, and seven others, although not statistically significant (P > 0.05), had mean values at least 0.5 mmol kg-1 lower at the higher temperature. The average change in intracellular [CO2] for all tissues examined was -0.165 mmol kg-1 degrees C-1. We conclude that, in cane toads, the temperature-related transients in RE result from intracellular CO2 adjustments, that different tissues have unique intracellular CO2/temperature relationships, and that a combination of respiratory and ion-exchange mechanisms is used to adjust pH as temperature changes.


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