Search results for "threshold"
showing 10 items of 688 documents
Tactile perceptual processes and their relationship to medically unexplained symptoms and health anxiety
2011
Abstract Objective The Somatic Signal Detection Task (SSDT; Lloyd, Manson, Brown and Poliakoff, 2008) is an innovative paradigm to study perceptual processes related to physical symptoms. It allows examining touch illusions as a laboratory analog of medically unexplained symptoms (MUS) according to the cognitive model of MUS proposed by Brown (2004). The present study compared psychopathologic measures of MUS and health anxiety with SSDT parameters. Furthermore, we aimed to define a reliable measurement of tactile perception threshold. Methods 67 participants of a student population reported whether they detected tactile stimuli at their fingertip which were presented in half of the test tr…
Trajectories of Blood Pressure Elevation Preceding Hypertension Onset: An Analysis of the Framingham Heart Study Original Cohort
2018
Importance Given that hypertension remains a leading risk factor for chronic disease globally, there are substantial ongoing efforts to define the optimal range of blood pressure (BP). Objective To identify a common threshold level above which BP rise tends to accelerate in progression toward hypertension. Design, Setting, and Participants This longitudinal, community-based epidemiological cohort study of adults enrolled in Framingham, Massachusetts, included 1252 participants (mean [SD] age, 35.3 [2.7] years) from the Framingham Original Cohort, of whom 790 (63.1%) were women. Each participant contributed up to 28 serial examinations of standardized resting BP measurements between 1948 and…
Light scattering in artificial fog and simulated with light scattering filter.
2009
Disability glare, affecting e.g. road safety at night, may result either from intraocular light scattering or from external conditions such as fog. Measurements were made of light scattering in fog and compared with intraocular straylight data for normal eyes and eyes with simulated cataract. All measurements were made with a direct compensation flicker method. To estimate light scattering levels in fog, straylight measurements were carried in a fog chamber for different densities of fog. Density was characterized by the meteorological term visibility V and ranged from 7 to 25. Test distance for measurements in the fog was constant at 5 m. Cataract eye conditions were simulated by placing a…
Effectiveness of High-Frequency Transcranial Magnetic Stimulation and Physical Exercise in Women With Fibromyalgia: A Randomized Controlled Trial
2020
Abstract Objective Fibromyalgia (FM) is characterized by chronic widespread pain and both physical and emotional alterations, which in turn may affect the individual’s quality of life. Thus, interventions aimed at treating such symptoms, without increasing fatigue, are needed. The aim of this study was to explore the effect of high-frequency transcranial magnetic stimulation (HF-TMS) and physical exercise (PE) on pain, impact of FM, physical conditioning, and emotional status in women with FM. Methods Forty-nine women with FM were randomly allocated to: (1) a PE group (PEG, n = 16), who underwent an 8-week (two 60-minute sessions/wk) low-intensity PE program; (2) a TMS group (TMSG, n = 17) …
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…
Differential nociceptive deficits in patients with borderline personality disorder and self-injurious behavior: laser-evoked potentials, spatial disc…
2003
Approximately 70-80% of women meeting criteria for borderline personality disorder (BPD) report attenuated pain perception or analgesia during non-suicidal, intentional self-mutilation. The aim of this study was to use laser-evoked potentials (LEPs) and psychophysical methods to differentiate the factors that may underlie this analgesic state. Ten unmedicated female patients with BPD (according to DSM-IV) and 14 healthy female control subjects were investigated using brief radiant heat pulses generated by a thulium laser and five-channel LEP recording. Heat pulses were applied as part of a spatial discrimination task (two levels of difficulty) and during a mental arithmetic task. BPD patien…
Identification of Subgroups of Women with Carpal Tunnel Syndrome with Central Sensitization.
2016
Identification of subjects with different sensitization mechanisms can help to identify better therapeutic strategies for carpal tunnel syndrome (CTS). The aim of the current study was to identify subgroups of women with CTS with different levels of sensitization.A total of 223 women with CTS were recruited. Self-reported variables included pain intensity, function, disability, and depression. Pressure pain thresholds (PPT) were assessed bilaterally over median, ulnar, and radial nerves, C5-C6 joint, carpal tunnel, and tibialis anterior to assess widespread pressure pain hyperalgesia. Heat (HPT) and cold (CPT) pain thresholds were also bilaterally assessed over the carpal tunnel and the the…
External and internal exposure to polycyclic aromatic hydrocarbons (PAH) among workers in the production of fire-proof materials – Proposal of a biol…
2006
In 1999, we introduced the German polycyclic aromatic hydrocarbons (PAH) study. The study was designed as a nation-wide investigation on workers exposed to PAH. One aim of the study was to establish biological monitoring guidance values (BMGVs) for different branches. Here, we report on the production of fire-proof materials. This branch of industry is typically confronted with high exposure to PAH and with PAH-induced occupational (cancer) diseases. One hundred and thirty-five employees participated in the course of seven sampling dates in four different plants in Germany. External exposure was determined by personal air monitoring of the 16 EPA-PAH. Human biological monitoring was accompl…
Impaired Cardiopulmonary Exercise Capacity in Patients With Hyperthyroidism
1996
Hyperthyroidism (H) has been implicated as a primary cause of decreased exercise tolerance. To our knowledge, analysis of respiratory gas exchange, an efficient noninvasive method in evaluating cardiopulmonary capacity, has not been performed in patients with H.Using cardiopulmonary exercise testing, 12 consecutive women with Graves' H were examined and controlled in euthyroidism (E). Eighteen women with E, in whom cardiac catheterization had ruled out heart disease, served as control subjects (C).The ventilatory anaerobic threshold was determined by means of the V-slope method. Ergometry was performed with patients in a semisupine position using a continuous ramp protocol of 20 W/min. Echo…
Effect of changing pulse rate on profile parameters of perceptual thresholds and loudness comfort levels and relation to ECAP thresholds in recipient…
2010
Abstract: The Nucleus CI24RE Freedom device offers higher stimulation rates and lower noise levels in action potential measurements (ECAPs) than previous devices. A study including ten European implant teams showed that the effect of changes in rate from 250 to 3500 pulses per second on tilt and curvature of the T and C profiles is insignificant. When changing rate one may change the levels at all electrodes by the same amount. Using an automated procedure ECAPs could be measured quickly and reliably at a noise level of only 1 μV. However, this did not result in improved correlations between the tilt and curvature parameters of the ECAP profiles and those of the T and C profiles. Average C …