Vibratory Stimuli Research Articles

Vibration detection in arthropods: Signal transfer, biomechanics and sensory adaptations

In arthropods, the detection of vibrational signals and stimuli is essential in several behaviours, including mate recognition and pair formation, prey detection, and predator evasion. These behaviours have been studied in several species of insects, arachnids, and crustaceans for vibration production and propagation in the environment. Vibration stimuli are transferred over the animals’ appendages and the body to vibrosensory organs. Ultimately, the stimuli are transferred to act on the dendrites of the mechanosensitive sensilla. We refer to these two different levels of transfer as macromechanics and micromechanics, respectively. These biomechanical processes have important roles in filtering and pre-processing of stimuli, which are not carried out by neuronal components of sensory organs. Also, the macromechanical transfer is posture-dependent and enables behavioural control of vibration detection. Diverse sensory organs respond to vibrations, including cuticular sensilla (slit sensilla, campaniform sensilla) and internal chordotonal organs. These organs provide various adaptations, as they occur at diverse body positions with different mechanical couplings as input pathways. Macromechanics likely facilitated evolution of vibrosensory organs at specific body locations. Thus, vibration detection is a highly complex sensory capacity, which employs body and sensory mechanics for signal filtering, amplification, and analysis of frequency, intensity and directionality.

Association of Two Opposing Responses Results in the Emergence of a Novel Conditioned Response.

Recent studies examining association of opposing responses, contrasting emotional valences, or counter motivational states have begun to elucidate how learning and memory processes can translate to clinical therapies for trauma or addiction. In the current study, association of opposing responses is tested in C. elegans. Due to its relatively simple and well-described nervous system, it was hypothesized that association of two oppositional stimuli presented in a delayed conditioning protocol would strengthen the behavioral response to the first stimulus (alpha conditioning). To test this, C. elegans were exposed to a tone vibration stimulus (to activate a mechanosensory-driven locomotor reversal response) paired with a blue light (to activate a forward locomotor response) at a 2-s delay. After five pairings, behavior was measured following a tone-alone stimulus. Worms that received stimulus pairing did not show an enhanced response to the first presented stimulus (tone vibration) but rather showed a marked increase in time spent in pause (cessation of movement), a new behavioral response (beta conditioning). This increase in pause behavior was accompanied by changes in measures of both backward and forward locomotion. Understanding the dynamics of conditioned behavior resulting from pairing of oppositional responses could provide further insight into how learning processes occur and may be applied.

User Participatory Design of a Wearable Focal Vibration Device for Home-Based Stroke Rehabilitation.

Stroke often leads to the significant impairment of upper limb function and is associated with a decreased quality of life. Despite study results from several interventions for muscle activation and motor coordination, wide-scale adoption remains largely elusive due to under-doses and low user compliance and participation. Recent studies have shown that focal vibration has a greater potential to increase and coordinate muscle recruitment and build muscle strength and endurance. This form of treatment could widely benefit stroke survivors and therapists. Thus, this study aimed to design and develop a novel wearable focal vibration device for upper limb rehabilitation in stroke survivors. A user participatory design approach was used for the design and development. Five stroke survivors, three physical therapists, and two occupational therapists were recruited and participated. This pilot study may help to develop a novel sustainable wearable system providing vibration-based muscle activation for upper limb function rehabilitation. It may allow users to apply the prescribed vibratory stimuli in-home and/or in community settings. It may also allow therapists to monitor treatment usage and user performance and adjust the treatment doses based on progression.

An Integrated Testing Solution for Piezoelectric Sensors and Energy Harvesting Devices

Abstract With the fast growth of wireless communications between nodes and sensor units and the increase of devices installed in remote places, and the development of IIoT applications, new requirements for power energy supply are needed to assure device functionality and data communication capabilities during extended periods of time. For these applications, energy harvesting takes place as a good solution to increase the autonomy of remote measuring solutions, since the usage of conventional power supply solutions has clear limitations in terms of equipment access and increased maintenance costs. In this context, regenerative energy sources such as thermoelectric, magnetic and piezoelectric based, as well as renewable energy sources, such as photovoltaic and wind based, among others, make the development of different powering solutions for remote sensing units possible. The main purpose of this paper is to present a flexible testing platform to characterize piezoelectric devices and to evaluate their performance in terms of harvesting energy. The power harvesting solutions are focused on converting the energy from mechanical vibrations, provided by different types of equipment and mechanical structures, to electrical energy. This study is carried out taking into account the power supply capabilities of piezoelectric devices as a function of the amplitude, frequency and spectral contents of the vibration stimulus. Several experimental results using, as an example, a specific piezoelectric module, are included in the paper.

FV 2 A new neurophysiological test protocol for the assessment of the somatosensory nervous system – from the laboratory to clinical application

During clinical routine diagnostics, the integrity of the somatosensory nervous system is assessed by somatosensory-evoked potentials (SEPs), analyzing Aβ-fiber function, the posterior funiculus, brainstem, and the somatosensory cortex (Muzyka and Estephan 2019). Nevertheless, SEPs cannot provide diagnostic information on small fibers (Cruccu et al. 2004), which form around 80% of the somatosensory nervous system. These small fibers are subdivided into heat-sensitive Aδ-fibers (AMH II), mechanosensitive Aδ-fibers (AMH I), cold-sensitive Aδ-fibers, and C-fibers (mediating noxious and warm stimuli; Gasser 1941). Therefore, a combination of specific tests is required to gain a complete electrophysiological assessment of the somatosensory nervous system or to detect loss of function for specific nerve fiber subtypes. Loss of function of specific subtypes of somatosensory nerve fibers are found in neuropathic disorders, such as polyneuropathy (Bönhof et al. 2017), radiculopathy (Carlstedt 2008; Cavanaugh et al. 1997), traumatic nerve injury (Rotshenker 2011), and others (Gomatos and Rehman 2021). Large-fiber neuropathies only affect thickly myelinated nerve fibers (such as hypocobalaminemia-associated neuropathies; (Franques et al. 2019; Stabler 2013)), while other neuropathic disorders begin by an affection of small fibers (Aδ- and C-fibers), such as chemotherapy-induced polyneuropathy (Timmins et al. 2020). Some neuropathies involve specific subtypes of small nerve fibers, such as a loss of function of cold-mediating Aδ-fibers during the early stage of Fabry‘s disease (Onishi and Dyck 1974). Here, we present a novel neurophysiological test protocol, which assesses a major part of the somatosensory nervous system by recording evoked potentials of touch, pinprick, vibration, heat/heat pain, cold, and warm stimuli. This test protocol was applied on healthy subjects in a first step and then transferred to patients with painful radiculopathy and painful polyneuropathy in a second step. The EP-measurements were compared to clinical data, nerve conduction studies as well as Quantitative Sensory Testing. We found several promising analogies to clinical features of the tested patients, which motivates us and hopefully other researchers to continue on this path with the goal to form a reliable and valid electrophysiological sensory tool that could be used as an outcome measure for future neurophysiological studies and in clinical routine diagnostics.

A PMNN‐PZT Piezoceramic Based Magneto‐Mechano‐Electric Coupled Energy Harvester

AbstractIt is desired to obtain a piezoceramic with a high piezoelectric coefficient and low dielectric loss simultaneously for energy harvester application. Herein, it is reported that the 0.025Pb(Mn1/3Nb2/3)O3‐0.525Pb(Ni1/3Nb2/3)O3‐0.135PbZrO3‐0.315PbTiO3 (PMNN‐PZT) ceramic exhibits superior piezoelectric charge parameter e33 of 37.74 pC m−2 and low dielectric loss tanδ of 0.45%. Furthermore, a PMNN‐PZT ceramic‐based magneto‐mechano‐electric coupled energy harvester (MMEC‐EH) with a varying‐stiffness cantilever is designed and fabricated, which shows the strong self‐resonance effect in response to a random, transient impulse vibration or magnetic field stimulus. The investigations show that under a 0.6 s pulse vibration stimulus, the MMEC‐EH can tune itself into self‐resonance damping oscillation lasting for six seconds at its resonance frequency of 16 Hz, and the produced maximum power is 1.96 mWRMS. Under both weak magnetic field and force‐field dual‐stimulus (Hac = 0.5 Oe and a = 0.05 g), the generated power density is about 60 mWRMS Oe−2g−2cm−3, which is one to two orders of magnitude higher than those previously reported MMEC‐EHs. Finally, the MMEC‐EH is successfully demonstrated to power temperature/humidity sensors, indicating its potential for harvesting both weak vibration and magnetic field energy from environments for self‐powered sensor application.

Acute Vascular Response of Hand to Force and Vibration

This study aimed to investigate the acute effect of grip and feed exertions on the vascular system at the fingers during exposure to hand-arm vibration (HAV), and to identify which active hand force situation would have the most effect on finger vascular function. A total of 12 individuals attended the test, and each of them were subjected to eight sets of force-and-vibration situations: four with combinations of forces and vibration, and four control ones with only hand forces applied. The vibration stimulus was applied on the right hand at 2.75 m/s2 with a frequency of 125 Hz for three minutes, during which the application of grip and feed forces were set at either 10 N or 50 N. The weakening of the finger vascular function was reflected by a reduction in the finger blood flow (FBF) and finger skin temperature (FST). They were tested on both hands at fixed intervals before, during and after the exposure for in-time measurement. Hand forces resulted in clear reductions in FBF and FST in exposed right fingers whether the force was exerted solely or combined with vibration. The greater the hand force (especially grip force), the stronger the vascular response, while the additional reductions in FBF and FST from vibration were not significant. In the non-exposed left fingers, no significant changes in finger circulation occurred in response to force or vibration. Generally, vibration-induced acute finger vasoconstriction was affected by the hand forces, in which hand force seemed to play a more important part than vibration. A larger grip force would lead to a greater loss in the digital circulation than feed force. Thus, the level of hand force exerted on the tool handle should be limited to reduce the risk of harm from HAV.

The Unfolding Space Glove: A Wearable Spatio-Visual to Haptic Sensory Substitution Device for Blind People.

This paper documents the design, implementation and evaluation of the Unfolding Space Glove—an open source sensory substitution device. It transmits the relative position and distance of nearby objects as vibratory stimuli to the back of the hand and thus enables blind people to haptically explore the depth of their surrounding space, assisting with navigation tasks such as object recognition and wayfinding. The prototype requires no external hardware, is highly portable, operates in all lighting conditions, and provides continuous and immediate feedback—all while being visually unobtrusive. Both blind (n = 8) and blindfolded sighted participants (n = 6) completed structured training and obstacle courses with both the prototype and a white long cane to allow performance comparisons to be drawn between them. The subjects quickly learned how to use the glove and successfully completed all of the trials, though still being slower with it than with the cane. Qualitative interviews revealed a high level of usability and user experience. Overall, the results indicate the general processability of spatial information through sensory substitution using haptic, vibrotactile interfaces. Further research would be required to evaluate the prototype’s capabilities after extensive training and to derive a fully functional navigation aid from its features.

Development and Trial of a Prototype Device for Sensorimotor Therapy in Patients with Distal Radius Fractures

This study examined the clinical feasibility of a prototype device (development name: Ghost) for facilitating range of motion (RoM) recovery in the acute phase in patients with distal radius fractures (DRF). The Ghost device involves the administration of a combination of vibratory and visual stimuli. We divided the patients into the Ghost (n = 10) and control group (n = 4; tendon vibration only) groups. The experimental interventions were administered between the day after surgery and day 7 postoperatively. Traditional hand therapy was provided to both groups once daily from day 7 until day 84 postoperatively and once a week from day 84 until the end of the intervention period. Because vibratory stimulation makes the patient focus on wrist flexion, the primary outcome was the arc of wrist flexion-extension on the injured side, which was measured on days 7, 14, 28, 42, 56, 70, and 84. Analysis of covariance was applied using a bootstrap method to evaluate changes over time and compare them between the groups. Analyses was performed after stratification by age and body mass index. Both interventions improved RoM over time in patients with DRF. Results showed that Ghost has greater efficacy for improving wrist RoM in DRF patients than vibration alone. Treatment with Ghost can result in good RoM improvement during the acute phase of DRF in young patients and those with and normal or low body mass index. Further study is needed to verify our findings and assess the extent of RoM recovery.

Complications of Transcutaneous Protheses - A Systematic Review of Publications Over the Past 10 Years.

Introduction Bone conduction implants, responsible for transmitting sound from an external processor to the inner ear, can be divided into active and passive, depending on the vibratory stimulus location. The use of transcutaneous device has increased, given its aesthetic appeal, the complications and limitations of percutaneous devices, and patient's treatment adherence, focusing mainly on efficacy. However, various complications are associated with the use of transcutaneous prosthesis, which can often be serious. Objective To approach the literature on complications involving transcutaneous bone-anchored prostheses through a systematic review of articles published in the past 10 years (2011–2021). Data Synthesis The MEDLINE, EMBASE, Scopus, and Cochrane Library databases were searched. All articles written in English reporting on currently available transcutaneous prosthesis implantation and its complications were selected. Studies on both children and adults were included. The data on complications were extracted, and complications were classified as minor or major and associated to each device used. Thirty-seven articles were included in the study, of which 14 were prospective cohort studies, 22 were retrospective case series, and 1 was a case report. Most studies (18) included both adults and children. Moreover, 901 implantations were performed, of which 552 implanted Baha Attract (Cochlear Ltd., Sydney, Australia), 244 implanted BoneBridge (MED-EL, Innsbruck, Austria), and 105 implanted Sophono (Sophono Inc., Boulder, CO, USA]). Furthermore, 192 adverse events were reported (total complication rate, 21.3%), with 161 minor complications (84.3%) and 31 major complications (16.1%). Conclusion Transcutaneous prosthesis is an audiological alternative with fewer complications than percutaneous prosthesis. However, its indication should be judicious because complications are common, and although most complications are minor, serious infections requiring explantation may develop.

Proprioceptive sensitivity to imposed finger deflections.

Hand proprioception, the sense of the posture and movements of the wrist and digits, is critical to dexterous manual behavior and to stereognosis, the ability to sense the three-dimensional structure of objects held in the hand. To better understand this sensory modality and its role in hand function, we sought to characterize the acuity with which the postures and movements of finger joints are sensed. To this end, we measured the ability of human subjects to discriminate changes in posture and speed around the three joints of the index finger. In these experiments, we isolated the sensory component by imposing the postures on an otherwise still hand, to complement other studies in which subjects made judgments on actively achieved postures. We found that subjects could reliably sense 12-16% changes in joint angle and 18-32% changes in joint speed. Furthermore, the acuity for posture and speed was comparable across the three joints of the finger. Finally, task performance was unaffected by the presence of a vibratory stimulus, calling into question the role of cutaneous cues in hand proprioception.NEW & NOTEWORTHY Manual dexterity and stereognosis are supported by two exquisite sensory systems, namely touch and proprioception. Here, we measure the sensitivity of hand proprioception and show that humans can sense the posture and movements of the fingers with great accuracy. We also show that application of a skin vibration does not impair sensitivity, suggesting that proprioceptive acuity relies primarily on receptors in the muscles (and possibly tendons) rather than the skin.

The Effects of Bilateral Phase-Dependent Closed-Loop Vibration Stimulation With Motor Imagery Paradigm.

Vibration stimulation has been shown to have the potential to improve the activation pattern of unilateral motor imagery (MI) and to promote motor recovery. However, in the widely used left and right hand MI brain-computer interface (BCI) paradigm, the vibration stimuli cannot be directly applied to the imaginary side due to the spontaneity of imagery. In this study, we proposed a method of phase-dependent closed-loop vibration stimulation to be applied on both hands, and explored the effects of different vibration stimuli on the left and right hand MI-BCI. Eighteen healthy subjects were recruited and asked to perform, in sequence, MI tasks under three different conditions of vibratory feedback, which were no vibration stimulus (MI), phase-dependent closed-loop vibration stimulus (PDS), and continuous vibration stimulus (CS). Then the performance of the left and right hand MI-BCI and the patterns of brain oscillation were compared and analyzed under these different stimulation conditions. The results showed that vibration stimulation effectively boosted the activation of the sensorimotor cortex and enhanced the functional connectivity among sensorimotor-related brain regions during MI. The closed-loop stimulation evoked stronger event-related desynchronization patterns on the contralateral side of the imagined hand compared to continuous stimulation. There was a more obvious distinction between left hand task and right hand task. In addition, phase-dependent closed-loop vibration stimulation increased classification accuracy by approximately 7% (paired t-test, p=0.004, n=18) compared to MI alone, while continuous vibration stimulation only increased it by 4% (paired t-test, p=0.067, n=18). This result further demonstrated the effectiveness of the phase-dependent closed-loop vibration stimulation method in improving the overall performance of the MI paradigm and is expected to be further applied in areas such as stroke rehabilitation in the future.

Development of Kinesthetic Illusion Presentation System Considering the Muscle and Tendon Parameters

The kinesthetic illusion phenomenon is attracting attention as one of the future rehabilitation techniques. The kinesthetic illusion is the illusion in which the proprioceptive sensation associated to the tendon and muscle occurs in the extension direction, when a vibration stimulus is given to the tendon. Our final goal is to control this kinesthetic sensation of this illusion with vibration stimulation. In this study, we construct a mathematical model of the kinesthetic illusion to realize this goal. We also conducted a psychophysical experiment to verify our proposed mathematical model of kinesthetic illusion. As a result of the experiment, it is clarified that the proposed model can express the relationship between the vibration stimulus and the amount of illusion. In the future work, we will develop the system which can control kinesthetic illusion which considers the proposed kinesthetic illusion model as well as the variation of the property of muscle.

Characteristics of osteoblastic calcium signaling response to microvibration stimuli

In this study, osteoblasts were subjected to LMHF vibration stimulation with different acceleration amplitudes and vibration with pause periods, and characteristics of the intracellular calcium signaling response were evaluated. As a result, the peak intensity of the calcium signaling response was higher for the vibration stimulus with higher acceleration amplitude. However, LMHF vibration stimulation with pause periods did not have a statistically significant effect on the response rate, response peak intensity, or response time. These results indicate that osteoblasts have the ability to sense the intensity of LMHF vibration stimuli and respond more strongly to vibration with higher acceleration amplitude. In addition, the insertion of a pause periods into the vibration did not affect the response characteristics of osteoblasts.

Observation of time course changes of actin cytoskeleton in osteoblasts under micro vibration stimuli

Observation of time course changes of actin cytoskeleton in osteoblasts under micro vibration stimuli

Object Recognition via Evoked Sensory Feedback during Control of a Prosthetic Hand.

Haptic and proprioceptive feedback is critical for sensorimotor integration when we use our hand to perform daily tasks. Here, we evaluated how externally evoked haptic and proprioceptive feedback and myoelectric control strategies affected the recognition of object properties when participants controlled a prosthetic hand. Fingertip haptic sensation was elicited using a transcutaneous nerve stimulation grid to encode the prosthetic's fingertip forces. An array of tactors elicited patterned vibratory stimuli to encode tactile-proprioceptive kinematic information of the prosthetic finger joint. Myoelectric signals of the finger flexor and extensor were used to control the position or velocity of joint angles of the prosthesis. Participants were asked to perform object property (stiffness and size) recognition, by controlling the prosthetic hand with concurrent haptic and tactile-proprioceptive feedback. With the evoked feedback, intact and amputee participants recognized the object stiffness and size at success rates ranging from 50% to 100% in both position and velocity control with no significant difference across control schemes. Our findings show that evoked somatosensory feedback in a non-invasive manner can facilitate closed-loop control of the prosthetic hand and allowed for simultaneous recognition of different object properties. The outcomes can facilitate our understanding on the role of sensory feedback during bidirectional human-machine interactions, which can potentially promote user experience in object interactions using prosthetic hands.

Caracterização da magnitude da vibração imposta por plataformas vibratórias estocásticas de corpo inteiro utilizadas em reabilitação e treinamento: estudo preliminar

Abstract The use of devices that produce stochastic whole-body vibration as a resource for rehabilitation and training programs has been founded on the theory of stochastic resonance. However, the prescription of rehabilitation and training programs must be preceded by the verification of imposed-vibration magnitude and of how it can be affected by the presence of an individual on the devices. The aim of this research was to characterize and analyze the effect of an individual's mass on the vibratory stimulus provided by stochastic whole-body vibration (SWBV) devices. The sample consisted of 30 repetitions for each one of the 6 vibration levels of the SWBV device (level 02, 04, 06, 08, 10 and 12), performed in two experimental situations (Without Load; Load [70Kg]; ≈ 35 kg on the right and left surfaces of the platform). For the antero-posterior, latero-lateral, and vertical directions, all variables showed significant differences between treatments, levels and interaction between experimental factors (p<.05), except for the Disp variable between treatments (p=.075). To measure vibration magnitude, a triaxial accelerometer was attached at the center of the board of one of the platform surfaces. Load interferes with parameters of vibration imposed by SWBV platforms, increasing ARMS and APEAK in the latero-lateral and antero-posterior directions, reducing these same parameters in the vertical direction.

The combined effect of extraoral vibratory stimulus and external cooling on pain perception during intra-oral local anesthesia administration in children: a systematic review and meta-analysis.

This study aimed to assess the combined use of extraoral vibratory stimulation and extraoral cooling in reducing the pain (subjective and objective) of dental local anesthesia administration in children.PubMed, Cochrane Central Register of Controlled Trials, and Ovid SP databases were searched up to July 2021. Article titles were screened and full-text evaluations of the selected articles were performed. Finally, seven studies (391 children, aged 4 – 12 years) were included in this qualitative and quantitative analysis. The pooled data determined the combined effect of extraoral vibration and extraoral cooling as a single measure. Extraoral vibration or cooling alone were not compared. The measured primary and secondary outcomes were pain perception and subjective and objective pain, respectively. When compared with the control, extraoral vibration and cooling resulted in significant differences in the mean combined data for the variables, pain perception, and pain reaction. Children’s subjective pain as measured by pain scores were reduced when extraoral vibration and cooling was used during local anesthesia administration (mean difference -3.52; 95% confidence interval [-5.06 - 1.98]) and objective pain (mean difference -1.46; 95% confidence interval [-2.95 - 0.02] ; mean difference -1.93; 95% confidence interval [-3.72 - 0.14]).Within the confines of this systematic review, there is low-quality evidence to support the use of combined extraoral vibration and cooling for reducing pain (subjective and objective) during intraoral local anesthesia administration in children.

指先への振動提示による重さ錯覚と把持力調整の関係

指先への振動提示による重さ錯覚と把持力調整の関係

Four-week whole-body vibration training and its effects on strength, power and sprint performance in young basketball players - a randomized control trial

We aimed to investigate whether the addition of whole-body vibration (WBV) to resistance training (RT) will be more beneficial in improving lower limbs muscle strength, power and sprinting performance than RT alone in young basketball players. We recruited 30 young basketball players to participate in four weeks of training and assessments. They were randomized into the WBV resistance training group (VRTG, n=15) and a conventional resistance training group (RTG, n=15), performed 3 times per week. At the beginning and end of the four weeks a back squat one-repetition maximum (1RMBS), Countermovement jump (CMJ), Squat jump (SJ), 10 meters (10m) and 20 meters sprint (20m) were performed. We found that: a) VRTG when added to RT can induce greater improvements in 1RMBS (percentage difference [PD], 8.4%, p < 0.001), CMJ (PD = 4.7%, p = 0.001) and SJ (PD = 1.6, p = 0.02) than RT alone. In contrary, significant time*group interactions were found for sprint times at 10m (p=0.08, F=3.2) and 20m (p=0.17, F=1.93). An additional 4-week WBV resistance training program proved effective in improving lower limb power and strength in young basketball players. When performed on a vibration platform (with accurate and constant vibration stimulus parameters), the resistance exercises were superior to their conventional forms and resulted in additional gains on measures of muscle power and strength, while sprint performance remained unchanged.