title: Effect of age on ocular microtremor activity.
abstract: BACKGROUND
  Ocular microtremor (OMT) is a high-frequency tremor of the eyes. It is present in all individuals and is related to brainstem activity. The OMT signal appears as an irregular oscillatory movement with intermittent burst-like components. The clinical interest in OMT has centered on its use in the assessment of the comatose patient, with broad agreement among authors of its prognostic value. The purpose of this study was to examine the changes in OMT activity related to aging.
  
  
  METHODS
  OMT was recorded from 72 normal healthy subjects using the piezoelectric strain gauge technique. The subjects ranged in age from 21 to 88 years (54.22 +/- 20.43 years, mean +/- SD).
  
  
  RESULTS
  Our results show that the overall frequency and frequency content of the bursts falls with age (p < .002 and p < .001, respectively). There is a highly significant drop in all three frequency parameters of OMT (p < .0001) in subjects older than 60 years of age.
  
  
  CONCLUSIONS
  These results suggest that different values of normality should operate for subjects over 60 years of age when considering the clinical application of OMT.
authors.affiliation: Department of Neurosurgery, Frenchay Hospital, Bristol, UK.
authors.forename: C
authors.initials: C
authors.lastname: Bolger
authors.forename: S
authors.initials: S
authors.lastname: Bojanic
authors.forename: N F
authors.initials: NF
authors.lastname: Sheahan
authors.forename: D
authors.initials: D
authors.lastname: Coakley
authors.forename: J F
authors.initials: JF
authors.lastname: Malone
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D008875:Middle Aged; D009801:Oculomotor Muscles / Q000503:physiopathology*; D012016:Reference Values; D012044:Regression Analysis; D014159:Transducers; D014202:Tremor / Q000503:physiopathology*