title: Auditory startle reflex and startle reflex to somatosensory inputs in generalized dystonia.
abstract: OBJECTIVE
  Startle reflex is a generalized defense reaction after unexpected auditory, visual, or tactile stimuli. Auditory startle reflex (ASR) and startle reflex to somatosensory inputs (SSS) have never been studied in generalized dystonia. Here, we aimed to study the characteristics and changes of ASR and SSS in this group.
  
  
  METHODS
  We have examined ASR and SSS in patients with generalized dystonia (n=11) and healthy subjects (n=25) under the same conditions. ASRs and SSSs were recorded over the orbicularis oculi (O.oc), sternocleidomastoid, biceps brachii (BB), and abductor pollicis brevis (APB) muscles after bilateral auditory stimulation and unilateral median nerve electrical stimulation at the wrist, respectively.
  
  
  RESULTS
  Both ASR and SSS showed the same sequence of muscle activation in both groups. However, the presence rates over the APB and BB muscles after both modalities of stimuli were significantly higher in the generalized dystonia group. ASR did not habituate in the dystonia group.
  
  
  CONCLUSIONS
  Both ASR and SSS are disinhibited, and both show a similar sequence of muscle recruitment in generalized dystonia.
  
  
  CONCLUSIONS
  Higher probabilities over caudal muscles probably depend on the higher excitability of motor neurons secondary to central modulation.
authors.affiliation: Department of Neurology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Meral E
authors.initials: ME
authors.lastname: Kiziltan
authors.affiliation: Department of Neurology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey. Electronic address: draysegulgunduz@yahoo.com.
authors.forename: Aysegul
authors.initials: A
authors.lastname: Gunduz
authors.affiliation: Department of Neurology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Hulya
authors.initials: H
authors.lastname: Apaydın
authors.affiliation: Department of Neurology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Sibel
authors.initials: S
authors.lastname: Ertan
authors.affiliation: Department of Neurology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Gunes
authors.initials: G
authors.lastname: Kiziltan
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods*; D000293:Adolescent; D000328:Adult; D004421:Dystonia / Q000175:diagnosis* / Q000503:physiopathology*; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology; D013216:Reflex, Startle / Q000502:physiology*; D013003:Somatosensory Cortex / Q000503:physiopathology; D055815:Young Adult
keywords: Auditory startle reflex; Generalized dystonia; Startle reflex to somatosensory inputs