Search results for "Thermosensing"
showing 10 items of 17 documents
Thermosensory mapping of skin wetness sensitivity across the body of young males and females at rest and following maximal incremental running
2019
Key points: Humans lack skin receptors for wetness (i.e. hygroreceptors), yet we present a remarkable wetness sensitivity. Afferent inputs from skin cold-sensitive thermoreceptors are key for sensing wetness; yet, it is unknown whether males and females differ in their wetness sensitivity across their body and whether high intensity exercise modulates this sensitivity. We mapped sensitivity to cold, neutral and warm wetness across five body regions and show that females are more sensitive to skin wetness than males, and that this difference is greater for cold than warm wetness sensitivity. We also show that a single bout of maximal exercise reduced the sensitivity to skin wetness (i.e. hyg…
Different Brain Circuitries Mediating Controllable and Uncontrollable Pain.
2015
Uncontrollable, compared with controllable, painful stimulation can lead to increased pain perception and activation in pain-processing brain regions, but it is currently unknown which brain areas mediate this effect. When pain is controllable, the lateral prefrontal cortex (PFC) seems to inhibit pain processing, although it is unclear how this is achieved. Using fMRI in healthy volunteers, we examined brain activation during controllable and uncontrollable stimulation to answer these questions. In the controllable task, participants self-adjusted temperatures applied to their hand of pain or warm intensities to provoke a constant sensation. In the uncontrollable task, the temperature time …
Quantitative sensory testing in the German Research Network on Neuropathic Pain (DFNS): Standardized protocol and reference values
2006
The nationwide multicenter trials of the German Research Network on Neuropathic Pain (DFNS) aim to characterize the somatosensory phenotype of patients with neuropathic pain. For this purpose, we have implemented a standardized quantitative sensory testing (QST) protocol giving a complete profile for one region within 30 min. To judge plus or minus signs in patients we have now established age- and gender-matched absolute and relative QST reference values from 180 healthy subjects, assessed bilaterally over face, hand and foot. We determined thermal detection and pain thresholds including a test for paradoxical heat sensations, mechanical detection thresholds to von Frey filaments and a 64 …
Somatosensory profiles in subgroups of patients with myogenic temporomandibular disorders and Fibromyalgia Syndrome.
2009
Some patients with myofascial pain from temporomandibular disorders (TMD) report pain in extra-trigeminal body regions. Our aim was to distinguish TMD as regional musculoskeletal pain syndrome (n=23) from a widespread pain syndrome (FMS; n=18) based on patients' tender point scores, pain drawings and quantitative sensory testing (QST) profiles. Referenced to 18 age- and gender-matched healthy subjects significant group differences for cold, pressure and pinprick pain thresholds, suprathreshold pinprick sensitivity and mechanical detection thresholds were found. Pain sensitivity in TMD patients ranged between those of FMS patients and healthy controls. The group of TMD patients was inhomogen…
Effects of transcranial direct current stimulation of the primary sensory cortex on somatosensory perception.
2011
Background: Transcranial direct current stimulation (tDCS) is able to modify cortical excitability and activity in humans. Objective: The aim of the present study was to analyze the effects of tDCS of the primary sensory cortex (SI) on thermal and mechanical perception, assessed by quantitative sensory testing (QST). Methods: The comprehensive QST protocol encompassing thermal and mechanical detection and pain thresholds as devised by the German Research Network on Neuropathic Pain (DFNS) was applied to skin areas innervated by the radial and median nerve of 12 healthy subjects, who were examined before and after each tDCS stimulation type. Anodal, cathodal, and sham tDCS was applied at a 1…
Transcranial direct current stimulation of the motor cortex induces distinct changes in thermal and mechanical sensory percepts
2009
Abstract Objective The aim of this single-blinded, complete crossover study was to evaluate the effects of tDCS on thermal and mechanical perception, as assessed by quantitative sensory testing (QST). Methods QST was performed upon the radial part of both hands of eight healthy subjects (3 female, 5 male, 25–41 years of age). These subjects were examined before and after cathodal, anodal or sham tDCS, applied in a random order. TDCS was administered for 15 min at a 1 mA current intensity, with the active electrode placed over the left primary motor cortex and the reference electrode above the right orbit. Results After cathodal tDCS, cold detection thresholds (CDT), mechanical detection thr…
Sensitivity to heat in MS patients: a factor strongly influencing symptomology -- an explorative survey
2011
Published version of an article to be found in BMC Neurology 2011, 11:27, http://dx.doi.org/10.1186/1471-2377-11-27 Background: Many individuals diagnosed with Multiple Sclerosis (MS) are sensitive to increased body temperature, which has been recognized as correlating with the symptom of fatigue. The need to explore this association has been highlighted. The aim of this study was to investigate the occurrence of heat sensitivity and its relations to disease course, disability, common MS-related symptoms and ongoing immunosuppressive treatments among individuals 65 years of age or younger diagnosed with MS. Methods: A cross-sectional designed survey was undertaken. A questionnaire was sent …
Neural correlates of antinociception in borderline personality disorder.
2006
Context A characteristic feature of borderline personality disorder (BPD) is self-injurious behavior in conjunction with stress-induced reduction of pain perception. Reduced pain sensitivity has been experimentally confirmed in patients with BPD, but the neural correlates of antinociceptive mechanisms in BPD are unknown. We predicted that heat stimuli in patients with BPD would activate brain areas concerned with cognitive and emotional evaluation of pain. Objective To assess the psychophysical properties and neural correlates of altered pain processing in patients with BPD. Design Case-control study. Setting A university hospital. Participants Twelve women with BPD and self-injurious behav…
Thermal sensation and cell adaptability
2013
Whole person adaptive comfort is discussed with reference to recent findings in molecular scale systems biology. The observations are upscaled to hypotheses relating to less traditional interpretations of thermal processes, which have new implications for indoor climate management and design. Arguments are presented for a revision of current focus, model and paradigm. The issue is seen as a problem of integrating theoretical development, conceptual modeling and as an investigation of the extent to which environments and acclimatization can be used to achieve individual fitness and health, not only at the subjective comfort level, as hitherto promoted. It is argued that there are many questi…
Acetylsalicylic acid reduces heat responses in rat nociceptive primary sensory neurons – evidence for a new mechanism of action
2002
Acetylsalicylic acid (ASA) is thought to exert its peripheral analgesic effects via inhibition of cyclooxygenase. We now studied the effects of ASA on heat responses in primary nociceptive neurons by whole-cell patch-clamp and calcium microfluorimetry experiments. Heat-evoked inward currents in acutely dissociated rat dorsal root ganglion neurons were significantly reduced by ASA in a dose-dependent and reversible manner (IC(50) 375 nM, Hill slope -2.2, maximum effect 55%). Heat-evoked calcium transients (measured with FURA-2) were reversibly reduced by 53+/-14% (P0.05) by co-application of 1 microM ASA. The low IC(50) value, the rapid occurrence, and the reversibility of the observed effec…