Dissociated effects of quiet stance on standard and high-frequency (600Hz) lower limb somatosensory evoked potentials
| Autor: | Barbara Micoli, Rachele Fantinel, Ivana Del Piero, Giacomo Della Marca, Domenico Restuccia, Monica Cazzagon |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Adult
Male Time Factors Supine position Posture Stimulation Gating Somatosensory system Evoked Potentials Somatosensory Physiology (medical) Humans Evoked potential Tibial nerve Spectrum Analysis Dose-Response Relationship Radiation Somatosensory Cortex Middle Aged Electric Stimulation Sensory Systems body regions Electrophysiology Lower Extremity Neurology Somatosensory evoked potential Female Neurology (clinical) Tibial Nerve Psychology Neuroscience |
| Zdroj: | Clinical Neurophysiology. 119:1408-1418 |
| ISSN: | 1388-2457 |
| Popis: | Objective To verify whether standing can modulate somatosensory input from lower limb to the cortex. Somatosensory afferents have been evaluated not only by means of somatosensory evoked potentials recorded by means of classical wide-bandpass filtering (standard SEPs), but also by high-frequency somatosensory evoked potentials (HF-SEPs), which probably play a role in the processing of rapid adaptive changes. Methods Eight healthy subjects underwent right posterior tibial nerve (PTN) stimulation in two different conditions (standing and lying supine). Standard SEPs reflecting the activity of both subcortical and cortical generators further underwent digital filtering (300–800 Hz), in order to enhance HF-SEP components. Results Stance significantly reduces the P40 cortical component of standard SEPs. By contrast, HF-SEPs did not show any significant change between the two conditions. Conclusions The lack of any gating effect on HF-SEPs lends further substance to the hypothesis that HF-SEPs play a pivotal role in the processing of somatosensory inputs related to rapid adaptive changes. Significance Our data confirm that standard and HF-SEPs reflect two distinct mechanisms with strongly different functional significance. Further studies are needed to definitively establish whether this dissociation is merely caused by the activation of anatomically different neuronal pools, or by the involvement of distinct functional mechanisms. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect