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ELife Aug 2019The established view is that vibrotactile stimuli evoke two qualitatively distinctive cutaneous sensations, flutter (frequencies < 60 Hz) and vibratory hum (frequencies...
The established view is that vibrotactile stimuli evoke two qualitatively distinctive cutaneous sensations, flutter (frequencies < 60 Hz) and vibratory hum (frequencies > 60 Hz), subserved by two distinct receptor types (Meissner's and Pacinian corpuscle, respectively), which may engage different neural processing pathways or channels and fulfil quite different biological roles. In psychological and physiological literature, those two systems have been labelled as Pacinian and non-Pacinian channels. However, we present evidence that low-frequency spike trains in Pacinian afferents can readily induce a vibratory percept with the same low frequency attributes as sinusoidal stimuli of the same frequency, thus demonstrating a universal frequency decoding system. We achieved this using brief low-amplitude pulsatile mechanical stimuli to selectively activate Pacinian afferents. This indicates that spiking pattern, regardless of receptor type, determines vibrotactile frequency perception. This mechanism may underlie the constancy of vibrotactile frequency perception across different skin regions innervated by distinct afferent types.
Topics: Action Potentials; Adult; Female; Healthy Volunteers; Humans; Male; Mechanoreceptors; Sensory Thresholds; Touch; Touch Perception; Young Adult
PubMed: 31383258
DOI: 10.7554/eLife.46510 -
Asia-Pacific Journal of Sports... Oct 2018Active restraint for the elbow joint is provided by the soft tissue component, which consists of a musculoligamentous complex. A lesion of the lateral collateral...
BACKGROUND
Active restraint for the elbow joint is provided by the soft tissue component, which consists of a musculoligamentous complex. A lesion of the lateral collateral ligament complex (LCLC) is thought to be the primary cause of posterolateral rotatory instability in the elbow. Its role as a protective reflexogenic structure is supported by the existence of ultrastructural mechanoreceptors. The aim of this study was to describe the existence and distribution of LCLC mechanoreceptors in the human elbow joint and to determine their role in providing joint stability.
METHODS
Eight LCLCs were harvested from fresh frozen cadaver elbows. Specimens were carefully separated from the lateral epicondyle and ulna. The ligament complex was divided into 7 regions of interest and stained with modified gold chloride. Microscopic evaluation was performed for Golgi, Ruffini, and Pacinian corpuscles. The number, distribution, and density of each structure were recorded.
RESULTS
Golgi, Ruffini, and Pacinian corpuscles were observed in LCLCs, with variable distribution in each region of interest. Ruffini corpuscles showed the highest total mechanoreceptor density. Mechanoreceptor density was higher at bony attachment sites.
CONCLUSION
The existence and role of each mechanoreceptor defined the purpose of each region of interest. Mechanoreceptors are beneficial for its proprioceptive feature towards a successful elbow ligament reconstruction.
PubMed: 30302315
DOI: 10.1016/j.asmart.2018.04.001 -
Tomography (Ann Arbor, Mich.) Sep 2022Anatomically accurate models of a human finger can be useful in simulating various disorders. In order to have potential clinical value, such models need to include a...
Anatomically accurate models of a human finger can be useful in simulating various disorders. In order to have potential clinical value, such models need to include a large number of tissue types, identified by an experienced professional, and should be versatile enough to be readily tailored to specific pathologies. Magnetic resonance images were acquired at ultrahigh magnetic field (7 T) with a radio-frequency coil specially designed for finger imaging. Segmentation was carried out under the supervision of an experienced radiologist to accurately capture various tissue types (TTs). The final segmented model of the human index finger had a spatial resolution of 0.2 mm and included 6,809,600 voxels. In total, 15 TTs were identified: subcutis, Pacinian corpuscle, nerve, vein, artery, tendon, collateral ligament, volar plate, pulley A4, bone, cartilage, synovial cavity, joint capsule, epidermis and dermis. The model was applied to the conditions of arthritic joint, ruptured tendon and variations in the geometry of a finger. High-resolution magnetic resonance images along with careful segmentation proved useful in the construction of an anatomically accurate model of the human index finger. An example illustrating the utility of the model in biomedical applications is shown. As the model includes a number of tissue types, it may present a solid foundation for future simulations of various musculoskeletal disease processes in human joints.
Topics: Humans; Magnetic Resonance Imaging; Fingers; Radio Waves; Tendons; Tendon Injuries
PubMed: 36287795
DOI: 10.3390/tomography8050196 -
PLoS Biology Aug 2019Motion is an essential component of everyday tactile experience: most manual interactions involve relative movement between the skin and objects. Much of the research on...
Motion is an essential component of everyday tactile experience: most manual interactions involve relative movement between the skin and objects. Much of the research on the neural basis of tactile motion perception has focused on how direction is encoded, but less is known about how speed is. Perceived speed has been shown to be dependent on surface texture, but previous studies used only coarse textures, which span a restricted range of tangible spatial scales and provide a limited window into tactile coding. To fill this gap, we measured the ability of human observers to report the speed of natural textures-which span the range of tactile experience and engage all the known mechanisms of texture coding-scanned across the skin. In parallel experiments, we recorded the responses of single units in the nerve and in the somatosensory cortex of primates to the same textures scanned at different speeds. We found that the perception of speed is heavily influenced by texture: some textures are systematically perceived as moving faster than are others, and some textures provide a more informative signal about speed than do others. Similarly, the responses of neurons in the nerve and in cortex are strongly dependent on texture. In the nerve, although all fibers exhibit speed-dependent responses, the responses of Pacinian corpuscle-associated (PC) fibers are most strongly modulated by speed and can best account for human judgments. In cortex, approximately half of the neurons exhibit speed-dependent responses, and this subpopulation receives strong input from PC fibers. However, speed judgments seem to reflect an integration of speed-dependent and speed-independent responses such that the latter help to partially compensate for the strong texture dependence of the former.
Topics: Adult; Animals; Female; Humans; Macaca mulatta; Male; Motion Perception; Movement; Neurons; Skin; Somatosensory Cortex; Touch; Touch Perception; Young Adult
PubMed: 31454360
DOI: 10.1371/journal.pbio.3000431 -
Journal of Shoulder and Elbow Surgery Apr 2021Sensory receptors in the joint capsule are critical for maintaining joint stability. However, the distribution of sensory receptors in the glenohumeral joint of the...
BACKGROUND AND HYPOTHESES
Sensory receptors in the joint capsule are critical for maintaining joint stability. However, the distribution of sensory receptors in the glenohumeral joint of the shoulder, including mechanoreceptors and free nerve endings, has not been described yet. This study aimed to describe the distributions of different sensory receptor subtypes in the glenohumeral joint capsule. Our hypotheses were as follows: (1) Sensory receptor subtypes would differ in density but follow a similar distribution pattern, and (2) the anterior capsule would have the highest density of sensory receptors.
METHODS
Six glenohumeral joint capsules were harvested from the glenoid to the humeral attachment. The capsule was divided into 4 regions of interest (anterior, posterior, superior, and inferior) and analyzed using modified gold chloride stain. Sensory receptors as well as free nerve endings were identified and counted under a light microscope from sections of each region of interest. The density of each sensory receptor subtype was calculated relative to capsule volume.
RESULTS
Sensory receptors were distributed in the glenohumeral joint capsule with free nerve endings. The anterior capsule exhibited the highest median density of all 4 sensory receptors examined, followed by the superior, inferior, and posterior capsules. The median densities of these sensory receptor subtypes also significantly differed (P = .007), with type I (Ruffini corpuscles) receptors having the highest density (2.97 U/cm), followed by type IV (free nerve endings, 2.25 U/cm), type II (Pacinian corpuscles, 1.40 U/cm), and type III (Golgi corpuscles, 0.24 U/cm) receptors.
CONCLUSION
Sensory receptor subtypes are differentially expressed in the glenohumeral joint capsule, primarily type I and IV sensory receptors. The expression of sensory receptors was dominant in the anterior capsule, stressing the important role of proprioception feedback for joint stability. The surgical procedure for shoulder instability should consider the topography of sensory receptors to preserve or restore the proprioception of the shoulder joint.
Topics: Aged; Cadaver; Female; Humans; Joint Capsule; Joint Instability; Male; Mechanoreceptors; Middle Aged; Nerve Endings; Proprioception; Sensory Receptor Cells; Shoulder Joint
PubMed: 32707328
DOI: 10.1016/j.jse.2020.07.006 -
Attention, Perception & Psychophysics Aug 2020It has been shown that vibrotactile stimuli elicit sound perception either on their own or by enhancing otherwise inaudible sounds. For taking advantage of this...
It has been shown that vibrotactile stimuli elicit sound perception either on their own or by enhancing otherwise inaudible sounds. For taking advantage of this phenomenon in the design of vibrotactile interfaces, it is important to identify its properties with respect to the level of the excitation frequency. The aim of this work is to further substantiate previous research results that indicate a prevalence of this phenomenon at a specific range of frequencies (200-390 Hz), which roughly pertains to the Pacinian corpuscle's maximum sensitivity range. Thirteen young adults participated in the study, which included comparison between sound-and-vibration versus sound-only signals. Masking background noise and no-touch control experiments were included to further support the outcome. The results validate the hypothesis that vibrotactile excitation at the index fingertip can enhance otherwise inaudible tones in the specific range of frequencies.
Topics: Fingers; Humans; Sensory Thresholds; Touch Perception; Vibration; Young Adult
PubMed: 32342343
DOI: 10.3758/s13414-020-02025-y -
Spine Apr 2017We collected the samples of cervical intervertebral discs from patients with vertigo to examine the distribution and types of mechanoreceptors in diseased cervical disc.
STUDY DESIGN
We collected the samples of cervical intervertebral discs from patients with vertigo to examine the distribution and types of mechanoreceptors in diseased cervical disc.
OBJECTIVE
The aim of this study was to determine whether mechanoreceptors are distributed more abundantly in cervical discs from patients with cervical spondylosis, and whether they are related to vertigo.
SUMMARY OF BACKGROUND DATA
Previous limited studies have found that normal cervical intervertebral discs are supplied with mechanoreceptors that have been considered responsible for proprioceptive functions. Several clinical studies have indicated that the patients with cervical spondylosis manifested significantly impaired postural control and subjective balance disturbance.
METHODS
We collected 77 samples of cervical discs from 62 cervical spondylosis patients without vertigo, 61 samples from 54 patients with vertigo, and 40 control samples from 8 cadaveric donors to investigate distribution of mechanoreceptors containing neurofilament (NF200) and S-100 protein immunoreactive nerve endings.
RESULTS
The immunohistochemical investigation revealed that the most frequently encountered mechanoreceptors were the Ruffini corpuscles in all groups of cervical disc samples. They were obviously increased in the number and deeply ingrown into inner annulus fibrosus and even into nucleus pulposus in the diseased cervical discs from patients with vertigo in comparison with the discs from patients without vertigo and control discs. Only three Golgi endings were seen in the three samples from patients with vertigo. No Pacinian corpuscles were found in any samples of cervical discs.
CONCLUSION
The diseased cervical discs from patients with vertigo had more abundant distribution of Ruffini corpuscles than other discs. A positive association between the increased number and ingrowth of Ruffini corpuscles in the diseased cervical disc and the incidence of vertigo in the patients with cervical spondylosis was found, which may indicate a key role of Ruffini corpuscles in the pathogenesis of vertigo of cervical origin.
LEVEL OF EVIDENCE
1.
Topics: Adult; Aged; Cervical Vertebrae; Female; Humans; Immunohistochemistry; Intervertebral Disc; Male; Mechanoreceptors; Middle Aged; Neurofilament Proteins; Radiculopathy; S100 Proteins; Spinal Cord Diseases; Spondylosis; Vertigo
PubMed: 27438387
DOI: 10.1097/BRS.0000000000001801 -
Anatomical Record (Hoboken, N.J. : 2007) Dec 2017The occurrence of Pacinian corpuscles associated to lymph nodes is an anatomical rarity and very scarce information exists in this regard. Here we examined...
The occurrence of Pacinian corpuscles associated to lymph nodes is an anatomical rarity and very scarce information exists in this regard. Here we examined immunohistochemically four Pacinian corpuscles found in the close vicinity of the hiliar blood vessels of lymph nodes (2 cervical, 1 axillary, and 1 inguinal) during routine surgical pathology. Pacinian corpuscles were normally arranged and displayed a pattern of protein distribution as follows: the axon was positive for neurofilament proteins and neuron specific enolase, the inner core cells showed intense S100 protein and vimentin immunostaining while they were negative for glial fibrillary acidic protein, type IV collagen and glucose transporter 1; vimentin, type IV collagen, and glucose transporter 1 were also observed also in the outer-core and the capsule. These results are in agreement with those reported for cutaneous Pacinian corpuscles, demonstrating that the immunohistochemical profile of these corpuscles is independent of its anatomical localization. The possible functional significance of Pacinian corpuscles in lymph nodes is discussed. Anat Rec, 300:2233-2238, 2017. © 2017 Wiley Periodicals, Inc.
Topics: Acquired Immunodeficiency Syndrome; Aged; Aged, 80 and over; Hernia, Inguinal; Humans; Lymph Nodes; Middle Aged; Neoplasms; Pacinian Corpuscles
PubMed: 28806498
DOI: 10.1002/ar.23679 -
Diagnostics (Basel, Switzerland) Jul 2022Plantar fibromatosis, known as Ledderhose disease, is a neoplastic disease characterized by a locally-aggressive bland fibroblastic proliferation. Although Pacinian...
BACKGROUND
Plantar fibromatosis, known as Ledderhose disease, is a neoplastic disease characterized by a locally-aggressive bland fibroblastic proliferation. Although Pacinian corpuscles alterations are commonly described in palmar fibromatosis, there are still no references about Pacinian corpuscles alterations in the rarer plantar version.
METHODS
We present a case report where a wide cutaneous resection, including the plantar fascia was performed, allowing a detailed study of Pacinian corpuscles. Pacinian corpuscles were analyzed using immunohistochemistry for neurofilament proteins, S100 protein, CD34, vimentin, glucose transporter 1, epithelial membrane antigen, neural-cell adhesion molecule, actin, desmin, type IV collagen, and high-affinity neurotrophin Trk-receptors. Moreover, the density and the size of the corpuscles were determined.
RESULTS
A clear increase in the number (hyperplasia) of Pacinian corpuscles was evidenced in the Ledderhose disease plantar fascia in comparison with similarly aged normal subjects. Pacinian hypertrophy was not demonstrated, but a significant decrease in the number of corpuscular lamellae was noted, with a subsequent increase in the interlamellar spaces. Pacinian corpuscles from the pathological plantar fascia showed an abnormal structure and immunohistochemical profile, generally without identifiable axons, and also absence of an inner core or an intermediate layer. Moreover, other molecules related with trophic maintenance of corpuscles were also absent. Finally, a vascular proliferation was commonly noted in some corpuscles, which involved all corpuscular constituents.
CONCLUSION
The observed Pacinian corpuscles hyperplasia could be considered a diagnostic clue of plantar fibromatosis.
PubMed: 35885610
DOI: 10.3390/diagnostics12071705 -
Journal of Pediatric Urology Mar 2024Circumcision is a surgical operation that is frequently performed throughout the world due to religious, cultural, and medical reasons. The best age for circumcision is...
BACKGROUND
Circumcision is a surgical operation that is frequently performed throughout the world due to religious, cultural, and medical reasons. The best age for circumcision is still debatable, with different procedures depending on geography, culture, and surgeon preference.
OBJECTIVE
This study aims to immunohistochemical examination using S100 staining and histologically evaluate the neurovascular structures in foreskin samples obtained from children aged 0-3 years and 6-11 years. The goal is to provide guidance in determining an appropriate age for circumcision based on these data.
STUDY DESIGN
Concerns regarding potential effects on glans sensitivity and sexual function led to the investigation and comparison of sensory innervation in the foreskin of children aged 0-3 and 6-11 years, a total 54 samples, divided into pre-phallic (0-3 years) and post-phallic (6-11 years) groups, were examined. The mean number of Meissner and Pacinian corpuscles, Ruffini endings, free nerve endings and the diameters of arteries were investigated.
RESULTS
Our findings show that compared to the 6-11 age group, the 0-3 age group had considerably lower sensory innervation in terms of, Meissner's corpuscles, Pacinian corpuscles, Ruffini endings and free nerve endings. Additionally, the diameter of arteries was noticeably smaller in the 0-3 age group.
CONCLUSIONS
In conclusion, this study supports the idea that circumcision performed in the early years of life may be associated with less adverse effects on neurovascular structures.
PubMed: 38580481
DOI: 10.1016/j.jpurol.2024.03.016