EMG sensor(Muscle sensor)

 The movement of our muscles is recorded using EMG (electromyography). It is based on the fact that when a muscle contracts, a burst of electric activity is generated that propagates through adjacent tissue and bone and can be recorded from nearby skin areas.

How do muscles move

Of course, the process starts in the brain. Triggering muscle movements begins in the motor cortex, where neural activity (a series of action potentials) signals to the spinal cord, and movement information is conveyed to the relevant muscle via motor neurons. This starts with upper motor neurons, which send signals to lower motor neurons.

Lower motor neurons initiate muscle movement because they innervate the muscle directly at the neuromuscular junction. This innervation causes the release of Calcium ions within the muscle, resulting in a mechanical change in muscle tension. EMG sensor can detect the difference in current because this process involves depolarization (a change in the electrochemical gradient).

How does EMG work?

Because EMG activity (measured in microvolts) is linearly related to the amount of muscle contraction as well as the number of contracted muscles — or in other words, the higher the recorded voltage amplitude, the stronger the muscle contraction and the greater the number of activated muscles.

EMG recordings represent an additional source of information into cognitive-behavioural processing that would be hidden based on pure observation because EMG activity is measurable even when we do not display obvious actions or even inhibit certain behaviours.

get started with EMG sensors

Make use of surface electrodes.

Surface EMG is a completely non-invasive technology that allows you to easily apply EMG electrodes to the skin using stickers.

EMG is an ideal method for monitoring physiological processes without interfering with established routines and movement patterns because the electrodes are non-invasive.

Always remember to clean the recording sites and remove makeup with alcohol rubs to obtain high-quality data.

Position EMG electrodes over the muscle groups of interest.

To be sure, this requires some anatomical knowledge. Only by understanding the muscle regimes involved in a specific action will you be able to obtain valid and reliable signals.

Choose an appropriate reference source.

Because EMG data is collected as the voltage difference between the recording site and the reference site, selecting an appropriate reference site is just as important as the recording site itself.