The ability to noninvasively assess voluntary muscle effort has wide application in physiologic studies, sports and rehabilitation medicine, as well as movement science. Traditionally, surface electromyography (sEMG) has been used for such assessments, but sEMG has several significant limitations arising from the fact that an estimate of muscle mechanical effort is being obtained from an electrical potential measurement made at the skin surface. As a result, it can be difficult to compare recordings from different muscles on the same person, on the same muscle over a period of days or weeks, or between the same muscle on different individuals. In addition, muscle fatigue studies are difficult as EMG activity tends to increase with increasing fiber recruitment, even though muscle effort is decreasing.
To overcome the limitations associated with using sEMG recordings to evaluate muscle effort, an increasing number of investigators have come to rely upon vibromyography (VMG), or the recording of muscle fiber vibrations, to estimate muscle effort levels. The development of microelectromechanical (MEMS) accelerometers has contributed greatly to this transition as extremely sensitive, very low noise sensors are now available at reasonable cost.
Electrodermal Activity (EDA) is an objective index for understanding emotional states. Researchers measure EDA to gain insights on psychological or physiological response, leading them down the path of scientific discovery. Because EDA is so important to research, BIOPAC has created tools to optimize event-related EDA analysis. Topics include: how to identify skin conductance responses, convert stim events from E-Prime SuperLab, Presentation, Vizard, etc., into AcqKnowledge events that can used for analysis, and score skin conductance responses using the AcqKnowledge automated EDA analysis tool.
NIRS and CNAP—Pairing great tools for great data Cerebral hemoglobin concentration (blood mass in the brain) is frequently measured in the prefrontal cortex, and systemic arterial blood pressure is known to be a variable factor based on the hemoglobin concentration. A leg pressure cuff was used to constrict and release blood flow to create a […]
BIOPAC’s just released 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 […]