Search results for "Pain threshold"

Central alterations of neuromuscular function and feedback from group III-IV muscle afferents following exhaustive high-intensity one-leg dynamic exe…

2015

The aims of this investigation were to describe the central alterations of neuromuscular function induced by exhaustive high-intensity one-leg dynamic exercise (OLDE, study 1) and to indirectly quantify feedback from group III-IV muscle afferents via muscle occlusion (MO, study 2) in healthy adult male humans. We hypothesized that these central alterations and their recovery are associated with changes in afferent feedback. Both studies consisted of two time-to-exhaustion tests at 85% peak power output. In study 1, voluntary activation level (VAL), M-wave, cervicomedullary motor evoked potential (CMEP), motor evoked potential (MEP), and MEP cortical silent period (CSP) of the knee extensor…

Peripheral Acute Pain Mechanisms

1995

Many studies in several species, including humans, have identified a subset of primary afferent nerve fibres that are activated by potential or actual tissue-damaging stimuli. Discharge patterns of these nociceptive afferents faithfully reproduce some aspects of the applied stimuli (e.g. shape of the stimulus-response function) but not others (e.g. time-course of a sustained stimulus). Since primary nociceptive afferents provide the input to the central nervous system, their encoding properties have to be considered when studying central processing. On the other hand, pain perception correlates with some aspects of nociceptor discharges (e.g. fatigue with repetition of brief heat pulses), b…

Capsaicin differentially modulates voltage-activated calcium channel currents in dorsal root ganglion neurones of rats

2005

It is discussed whether capsaicin, an agonist of the pain mediating TRPV1 receptor, decreases or increases voltage-activated calcium channel (VACC) currents (ICa(V)). ICa(V) were isolated in cultured dorsal root ganglion (DRG) neurones of rats using the whole cell patch clamp method and Ba 2+ as charge carrier. In large diameter neurones (>35Am), a concentration of 50AM was needed to reduce ICa(V) (activated by depolarizations to 0 mV) by 80%, while in small diameter neurones (30Am), the IC50 was 0.36 AM. This effect was concentration dependent with a threshold below 0.025 AM and maximal blockade (>80%) at 5AM. The current–voltage relation was shifted to the hyperpolarized direction with an…

Gadd45α modulates aversive learning through post‐transcriptional regulation of memory‐related mRNA s

2018

Abstract Learning is essential for survival and is controlled by complex molecular mechanisms including regulation of newly synthesized mRNAs that are required to modify synaptic functions. Despite the well‐known role of RNA‐binding proteins (RBPs) in mRNA functionality, their detailed regulation during memory consolidation is poorly understood. This study focuses on the brain function of the RBP Gadd45α (growth arrest and DNA damage‐inducible protein 45 alpha, encoded by the Gadd45a gene). Here, we find that hippocampal memory and long‐term potentiation are strongly impaired in Gadd45a‐deficient mice, a phenotype accompanied by reduced levels of memory‐related mRNAs. The majority of the Ga…

Pain elicited by blunt pressure: neurobiological basis and clinical relevance.

2002

Somatic Symptom Perception From a Predictive Processing Perspective: An Empirical Test Using the Thermal Grill Illusion.

2020

OBJECTIVE In a predictive processing perspective, symptom perceptions result from an integration of preexisting information in memory with sensory input. Physical symptoms can therefore reflect the relative predominance of either sensory input or preexisting information. In this study, we used the thermal grill illusion (TGI), which applies interlaced warm and cool temperatures to the skin to create a paradoxical heat-pain experience. Assuming that the TGI compared with single-temperature stimulation relies more importantly on an active integration process of the brain to create this paradoxical sensation, we tested the hypothesis whether a manipulation of the expectations during TGI would …

The direct effect of magnetic tape ® on pain and lower-extremity blood flow in subjects with low-back pain: A randomized clinical trial

2021

Low-back pain has a high impact on the world population, and solutions are in demand. The behavior of specific physiological processes has been modified using magnetic fields, whether for pain relief, bone consolidation, or improvement of vascularization. The use of tape with magnetic properties could help in these cases. A double-blind randomized clinical trial was designed to use Magnetic Tape® versus placebo Kinesio tape. Blood flow variables were evaluated using pulsed power Doppler ultrasound. Resistance index, pulsatility index, systolic velocity, and diastolic velocity were measured. The pressure pain threshold was measured using algometry in 22 subjects. The results reveal significa…

Physical Condition Factors that Predict a Better Quality of Life in Women with Fibromyalgia

2019

What physical qualities can predict the quality of life (QoL) in women with fibromyalgia (FM)? QoL is a very complex outcome affected by multiple comorbidities in people with fibromyalgia. This study aims to determine which physical qualities can predict the quality of life in women with FM. Also, a comparison between the physical qualities of women with FM and healthy counterparts was conducted. In total, 223 women participated in this cross-sectional study, 123 with FM, with ages ranging between 45 and 70 years. The study was conducted at several fibromyalgia associations and specialized medical units. QoL was measured as the main outcome. In addition, functional capacity, muscular streng…

The pain threshold of high-threshold mechanosensitive receptors subsequent to maximal eccentric exercise is a potential marker in the prediction of D…

2017

Background Delayed-onset muscle soreness (DOMS) refers to dull pain and discomfort in people after participating in exercise, sport or recreational physical activities. The aim of this study was to detect underlying mechanical thresholds in an experimental model of DOMS. Methods Randomised study to detect mechanical pain thresholds in a randomised order following experimentally induced DOMS of the non-dominant arm in healthy participants. Main outcome was the detection of the pressure pain threshold (PPT), secondary thresholds included mechanical detection (MDT) and pain thresholds (MPT), pain intensity, pain perceptions and the maximum isometric voluntary force (MIVF). Results Twenty volun…