Surface EMG crosstalk during phasic involuntary muscle activation in the nociceptive withdrawal reflex.
The human nociceptive withdrawal reflex is typically assessed using surface electromyography (sEMG). Based on sEMG, the reflex receptive field (RRF) can be mapped. However, EMG crosstalk can cause erroneous results in the RRF determination. Single differential (SD) vs. double differential (DD) surface EMG were evaluated. Different electrode areas and inter-electrode-distances (IED) were evaluated. The reflexes were elicited by electrical stimulation of the sole of the foot. EMG was obtained from both tibialis anterior (TA) and soleus (SOL) using both surface and intramuscular EMG (iEMG). The amount of crosstalk was significantly higher in SD recordings than in DD recordings (P < 0.05). Crosstalk increased when electrode measuring area increased (P < 0.05) and when IED increased (P < 0.05). Reflex detection sensitivity decreases with increasing measuring area and increasing IED. These results stress that for determination of RRF and similar tasks, DD recordings should be applied.
Integrative Neuroscience Group, Center for Sensory-Motor Interaction, Department of Health Science and Technology, Aalborg University, Fredrik Bajers vej 7D3 9220 Aalborg, Denmark. ksf@hst.aau.dk
Ken S
KS
Frahm
Michael B
MB
Jensen
Dario
D
Farina
Ole K
OK
Andersen
D000328:Adult; D004558:Electric Stimulation; D004576:Electromyography; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D059225:Nociception / Q000502:physiology*; D017288:Pain Threshold / Q000502:physiology; D012018:Reflex / Q000502:physiology*