title: Influence of parameter settings on paired-pulse-suppression in somatosensory evoked potentials: a systematic analysis.
abstract: OBJECTIVE
  Paired-pulse somatosensory evoked potentials (SEPs) are a common tool to investigate excitability in the human somatosensory cortex. Comparing literature about paired-pulse SEP, there is no standard set of stimulation parameters, while little is known about the influence of stimulation parameters on paired-pulse suppression.
  
  
  METHODS
  We analyzed changes of paired-pulse ratios by varying repetition rates from 1 to 9Hz, and using stimulus intensities of 250% of the sensory threshold and 100%, 120%, and 140% of the motor threshold, which are most frequently used in studies using paired-pulse SEPs.
  
  
  RESULTS
  We found a significant effect of repetition rate on paired-pulse suppression with increasing paired-pulse ratios from 1 to 9Hz, which is mainly caused by a change of single pulse amplitudes. We found no difference in paired-pulse suppression at the tested stimulation intensities.
  
  
  CONCLUSIONS
  The extent of paired-pulse ratios across different studies should be interpreted with caution due to the high dependence on repetition rate, while the results at the commonly used stimulus intensities are comparable.
  
  
  CONCLUSIONS
  For an optimized parameter setting with sufficient paired-pulse suppression, we suggest a stimulation rate of 1 or 3Hz and a stimulation intensity of 250% of sensory threshold or slightly above motor threshold.
authors.affiliation: Department of Neurology, Ruhr-University Bochum, BG-Kliniken Bergmannsheil, Bochum, Germany. oliver.hoeffken@ruhr-uni-bochum.de
authors.forename: Oliver
authors.initials: O
authors.lastname: Höffken
authors.forename: Janina
authors.initials: J
authors.lastname: Tannwitz
authors.forename: Melanie
authors.initials: M
authors.lastname: Lenz
authors.forename: Matthias
authors.initials: M
authors.lastname: Sczesny-Kaiser
authors.forename: Martin
authors.initials: M
authors.lastname: Tegenthoff
authors.forename: Peter
authors.initials: P
authors.lastname: Schwenkreis
mesh_terms: D000328:Adult; D004558:Electric Stimulation; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000502:physiology; D012684:Sensory Thresholds / Q000502:physiology; D013003:Somatosensory Cortex / Q000502:physiology*