title: F-wave and motor-evoked potentials during motor imagery and observation in apraxia of Parkinson disease.
abstract: BACKGROUND
  The amplitudes of F-waves and motor-evoked potentials (MEPs) increase during imagination or active motor performance. The aim of this study was to investigate F-wave and MEP facilitation during assessment of apraxia.
  
  
  METHODS
  Eight Parkinson disease (PD) patients with apraxia, 11 patients without apraxia, and 8 healthy volunteers were enrolled. F-waves and MEPs were recorded during 4 states (resting, imagination, observation, and active movement).
  
  
  RESULTS
  The mean amplitude of the F-waves increased significantly during imagination and active movement as compared with at rest in healthy individuals (P = 0.028) and in the nonapraxia group (P = 0.005). PD patients with apraxia did not have similar facilitation. The mean amplitude of the MEPs also showed a similar loss of facilitation in PD with apraxia.
  
  
  CONCLUSIONS
  Loss of facilitation during the preparation for movement is closely related to the "gold standard" clinical praxis battery. This study provides additional support and a potential electrophysiological assessment method for apraxia in PD.
authors: Department of Neurology, Cerrahpasa School of Medicine, Istanbul University, 34098, K.M. Pasa, Istanbul, Turkey.
authors: Ayşegül
authors: A
authors: Gündüz
authors: Department of Neurology, Cerrahpasa School of Medicine, Istanbul University, 34098, K.M. Pasa, Istanbul, Turkey.
authors: Meral E
authors: ME
authors: Kiziltan
mesh_terms: D000328:Adult; D000368:Aged; D001072:Apraxias / Q000209:etiology*; D004558:Electric Stimulation; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D007092:Imagination / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D010300:Parkinson Disease / Q000150:complications*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D012146:Rest; D018709:Statistics, Nonparametric; D050781:Transcranial Magnetic Stimulation
keywords: F-waves; Parkinson disease; apraxia; motor-evoked potentials; parkinsonism; transcranial magnetic stimulation