Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology
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The study addresses two controversial issues surrounding the nature of anticipatory postural adjustments (APAs). The first deals with the reproducible APA patterns in proximal postural muscles and variable APA patterns reported for the muscles controlling the ankle joint (TA-SOL). We hypothesized that the TA-SOL muscles participate mainly in the compensation of lateral and rotational perturbations, in particular those associated with asymmetrical movements. The second issue deals with decreased APAs reported during both very stable and unstable standing. We hypothesized that APA changes during unstable standing might depend on the actual mechanical nature of instability. ⋯ We conclude that the proximal muscles provide a general pattern counteracting expected perturbations in the anterior-posterior direction while the distal muscles deal with asymmetrical perturbations and the modulation of APAs in unusual conditions such as standing on rollerskates. There seems to be no unambiguous relation between the magnitude of APAs and the stability of standing: Depending on the exact mechanical nature of postural instability, it could be associated with qualitatively different changes in the APAs.
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The after-effect of transcutaneous electrical nerve stimulation (TENS) on pain-related brain responses was investigated using electroencephalography (EEG) and magnetoencephalography (MEG). ⋯ The results indicated that TENS reduced PREP following painful electrical stimulation, and that the origin of PREP was, at least partially, different from that of PRCF which was not changed after TENS. An after-effect of TENS significantly affected the generation process of PREP, but it was not enough to relieve the subjective painful feeling.
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To appraise the controversial prognostic significance of postanoxic alpha or theta coma (ATC). ⋯ This study and a review 283 cases of postanoxic ATC reported in the literature suggest the existence of incomplete and complete variants of postanoxic ATC. Whereas complete ATC is invariably associated with a poor outcome, full recovery is possible in patients with incomplete ATC. The combination of EEG, clinical, and SEP findings improves the prognostic accuracy of postanoxic ATC.
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To determine the effect of different sites and local skin temperature on thermal thresholds. ⋯ Testing of thermal thresholds in normal subjects can be adequately conducted at several sites at the hand, however, TE is preferred given the small inter-individual variability. TE may be preferred for evaluating hyperalgesia to cold given its higher threshold. Warming or cooling of the skin is unnecessary within the range normally encountered in routine clinical evaluation.
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The aim of this study is to assess Auditory Arousal Thresholds (AATs) three times during an undisturbed baseline night and to compare them to AATs during the recovery night that follows two consecutive nights of selective SWS deprivation. The presence of a time-of-night effect on AATs will also be assessed. ⋯ These results confirm that AATs are a reliable index of sleep depth by showing that the SWS rebound following selective SWS deprivation is paralleled by a significant AAT enhancement. The experimental paradigm also allows us to claim that AATs show a decreasing linear trend during the night, having excluded any procedural bias. Finally, AATs can be directly related to SWS amount that preceded the awakening, although the individual correlations between AATs and SWS have to be considered with caution, given the high inter-subject variability and the small number of observations.