title: Modulation of the sleep state-dependent P50 midlatency auditory-evoked potential by electric stimulation of acupuncture points.
abstract: OBJECTIVE
  To determine if the P50 midlatency auditory evoked potential, a sleep state-dependent waveform thought to be generated by the reticular activating system, is modulated after surface stimulation of acupuncture points (ie, electroacupuncture).
  
  
  METHODS
  P50 potential recordings were carried out before, during, and after electroacupuncture.
  
  
  METHODS
  A clinical research center.
  
  
  METHODS
  Eighty healthy subjects ages 25 to 55 were recorded in 7 investigations.
  
  
  METHODS
  Stimulation of 3 specific acupuncture points (Pericardium 6, Heart 3, Liver 3) was compared with no stimulation or with stimulation of control points (Gall Bladder 34, Large Intestine 11, Small Intestine 3). We compared different frequencies of stimulation (5, 60, 100 Hz), unilateral versus bilateral stimulation, and the effects of repeated episodes of stimulation.
  
  
  METHODS
  P50 auditory evoked potential latency, amplitude (measure of level of arousal), and habituation (measure of sensory gait) at interstimulus interval of 250 ms.
  
  
  RESULTS
  Electroacupuncture at specific points decreased P50 potential amplitude versus electroacupuncture at control points (P=.006) or versus no stimulation (P<.001). The optimal effective frequency was 5 Hz (P<.05 at 5 Hz, P>.05 at 60 and 100 Hz), and unilateral electroacupuncture was not as effective as bilateral electroacupuncture (P=.007). Repeated episodes of bilateral electroacupuncture showed additive effects (P<.05). There were no differences in responsiveness across sexes (P=.79), and electroacupuncture did not affect P50 potential habituation (P>.05).
  
  
  CONCLUSIONS
  Electroacupuncture may be effectively used to decrease arousal levels, perhaps as adjunct therapy for disorders of hypervigilance.
authors.affiliation: Center for Translational Neuroscience, Department of Neurobiology & Developmental Sciences, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Bray
authors.forename: Noriaki
authors.initials: N
authors.lastname: Mamiya
authors.forename: Alice V
authors.initials: AV
authors.lastname: Fann
authors.forename: Harris
authors.initials: H
authors.lastname: Gellman
authors.forename: Robert D
authors.initials: RD
authors.lastname: Skinner
authors.forename: Edgar E
authors.initials: EE
authors.lastname: Garcia-Rill
mesh_terms: D015669:Acupuncture Points; D000328:Adult; D004558:Electric Stimulation / Q000379:methods*; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006185:Habituation, Psychophysiologic; D006801:Humans; D008297:Male; D008875:Middle Aged; D012890:Sleep / Q000502:physiology*