For most biopotential recordings, it is important to provide a low impedance contact with the tissue underneath the skin at the electrode site. Consequently skin should be abraded with pumice, an ELPAD or ELPREP. Alcohol prep pads are generally not preferred because they dry the skin. The purpose of abrasion is to remove dead cells from the outer layer of skin. These cells form an electrical barrier. Electrical communication from the electrode surface to the underlying tissue is most often through a water-based gel. For good recordings, this gel must soak into the skin. As alcohol dries out the skin, it slows the process of establishing the liquid bridge between electrode and tissue.
One exception where abrasion is not recommended is measurement of electrodermal activity (skin conductance). Here skin should be rinsed but neither washed with soap nor abraded. As the conductivity of the skin at the electrode site is the variable to be measured in this case, no steps should be taken to modify that conductance artificially.
Smart Center Stand-alone, Portable Wireless Physiology Systems Smart Center Essentials entry-level system includes a Smart Center Device (BN-SMART with USB power cable), 2 or 3 Transmitters (BN-xxx-T with chargers); AcqKnowledge for Smart Center, and a case. Smart Center Enhanced adds a Logger (BN-LOGGER) and Basic Scripting License (ACK100W-BAS) to the Smart Center Device (BN-SMART with powercable), 3 […]
BIOPAC provides software and hardware that allows research teams to study stimulus presentation data. Here are a few notable studies using BIOPAC equipment for research on stimuli’s effects using ECG and SCL data. Your Face Scares Me This study addressed the impact of individual differences in social anxiety by examining the effects of perceptual load and stimulus valence when […]
BIOPAC’s comprehensive Introductory ECG Guide addresses fundamental to advanced concerns to optimize electrocardiography data recording and analysis. Topics include: ECG Complex; Electrical and Mechanical Sequence of a Heartbeat; Systole and Diastole; Configurations for Lead I, Lead II, Lead III, 6-lead ECG, 12-lead ECG, precordial leads; Ventricular Late Potentials (VLPs); ECG Measurement Tools; Automated Analysis Routines for extracting, […]