Intra-individual variation in oculomotor performance in man

Research output: Contribution to journalArticle


Peak velocity of saccade, maximum velocity of smooth pursuit, and peak velocity of slow phase of vestibular and optovestibular nystagmus were measured three times daily on three separate days in 6 healthy subjects in order to estimate the intra-individual variation of the results of oculomotor tests. Analysis of variance revealed that the oculomotor performance of the individual subjects varied systematically, depending on whether the tests were performed in the morning, at noon, or late in the afternoon. In particular, the velocity of saccade displayed lowest values in the afternoon. The present results indicate that oculomotor performance may depend on the individual biological rhythm of fatigue; however, it is also possible that eye motor behaviour is coupled to an independent rhythm of motor activity. Circadian rhythmicity of oculomotor performance should be considered in follow-up studies and in examination of patients with reduced vigilance.


  • L Schalén
  • I. Pyykkö
  • M Juhola
  • M Magnusson
  • V Jäntti
  • N.G. Henriksson
External organisations
  • Skåne University Hospital
  • University of Turku
Research areas and keywords


  • Adult, Circadian Rhythm, Electrooculography, Eye Movements, Female, Humans, Male, Oculomotor Muscles, Oculomotor Nerve, Reference Values, Journal Article
Original languageEnglish
Pages (from-to)212-7
JournalActa Oto-Laryngologica, Supplement
Issue numberS406
Publication statusPublished - 1984
Publication categoryResearch