stimulus artifact
Unwanted electrical signal produced by stimulation devices during evoked potential testing that can obscure or interfere with the neural response being measured.
Full Definition
Stimulus artifact is a technical challenge in evoked potential testing where the electrical or magnetic pulse used to stimulate nerves, muscles, or sensory organs creates unwanted signals that contaminate the recording system. This artifact appears as a large amplitude deflection at the time of stimulation and can mask the much smaller evoked responses of interest. Stimulus artifacts are particularly problematic in motor evoked potential studies using transcranial magnetic stimulation, where the magnetic pulse can induce significant electrical interference in nearby recording electrodes. Effective management of stimulus artifacts requires careful electrode placement, proper grounding, stimulus timing adjustments, and sometimes specialized blanking circuits. Understanding how to minimize and differentiate stimulus artifacts from genuine neural responses is essential for accurate evoked potential interpretation and valid clinical conclusions.
Usage
Usage note: Use lowercase unless at beginning of sentence; specify type when relevant
In Context
- "Large stimulus artifact obscured the early components of the somatosensory evoked potential response." — Evoked potential report
- "Adjusting the stimulator intensity reduced stimulus artifact while maintaining adequate neural activation." — Technical procedure note