Laplacian high-spatial-resolution surface electrode, isometric contraction. Hogrel J-Y, Pitié-Salpêtrière, Paris, FR.

High spatial resolution surface EMG signals were recorded from the biceps brachii during long, low level contractions. The aim of the study was to test if the main variables of the MUAPs were stable with respect to time during non fatiguing contractions. The variables considered were instantaneous IPI, CV and amplitude (computed for each MUAP).

Signal R01101 is 120 seconds long. Signal R01102 is 300 seconds long and is broken up into two parts: R01102a and R01102b. Each signal consists of 3 channels recorded with Laplacian electrodes. Sampling rate: 10 kz. Bandpass : 10-1kHz. The interelectrode distance was 5 mm. The contraction was isometric/isotonic as best as possible.

* Please cite this data as:
Hogrel J-Y. [Online dataset R011, available at http://www.emglab.net]

Curator's note: Signal R01101 illustrates some of the challenges involved in decomposing surface EMG signals. The signal contains four active MUs, but the MUAPs all have a very similar triphasic shape, differing only in amplitude. High-pass filtering at 100 Hz is helpful for smoothing the baseline, but any higher filtering reduces the signal-to-noise ratio unacceptably. Signal R01102 has a higher signal- to-noise ratio, but the MUAPs are still challenging to distinguish because of similarity of shape. The additional channels were recorded at different points along the muscle axis, and provide little additional discriminative information. The annotations were accomplished by the curator. They involved considerable manual editing and cannot be considered 100% reliable.

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