Neurological Sciences

, Volume 38, Issue 11, pp 1977–1984 | Cite as

Fixational eye movements in Tourette syndrome

  • Aasef G. ShaikhEmail author
  • Shlomit Ritz Finkelstein
  • Ronald Schuchard
  • Glen Ross
  • Jorge L. Juncos
Original Article


Studies of saccadic eye movements in subjects with Tourette syndrome (TS) have provided additional evidence that there is a link between TS symptoms and deficits in fronto-striato-thalamic networks. These studies revealed impaired timing and inhibition of saccades. We compared fixational eye movements, such as microsaccades and ocular drifts, in subjects with TS and healthy controls.We measured horizontal and vertical eye positions with video-oculography in 14 subjects with Tourette syndrome. We found reduced microsaccade amplitude but increased time between adjacent microsaccades (intersaccadic interval). Hence, the rate of microsaccades was reduced in subjects with TS compared to controls. Measure of ocular stability during intersaccadic intervals revealed increased drift velocity and increased variance in eye position. We hypothesize that increased activity of the direct fronto-striatal pathway and the resulting reduction in basal ganglia outflow targeting the superior colliculus fixation zone affect the rate and amplitude of microsaccades in subjects with TS. The resulting impairment in frontal eye field fixation leads to increased drifts during intersaccadic interval in subjects with TS. Possible clinical implication for these results is that fixational eye movements can be objective biological markers of TS.


Microsaccades Gaze holding Vision Tics Basal ganglia 


Compliance with ethical standards

The experiment protocol of this study complied with the tenets of the Declaration of Helsinki and was approved by the Emory University Institutional Review Board.

Funding statement

AS is supported by grant from Dystonia Medical Research Foundation and Dystonia Coalition. The authors have no financial conflicts related to the contents included in this manuscript.


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Copyright information

© © US Government (outside the USA) 2017

Authors and Affiliations

  • Aasef G. Shaikh
    • 1
    • 2
    • 3
    Email author
  • Shlomit Ritz Finkelstein
    • 4
  • Ronald Schuchard
    • 5
  • Glen Ross
    • 6
  • Jorge L. Juncos
    • 7
  1. 1.Depatment of NeurologyCase Western Reserve UniversityClevelandUSA
  2. 2.Daroff-DelOsso Ocular Motility Laboratory and Neurology ServiceLouis Stokes VA Medical CenterClevelandUSA
  3. 3.Department of NeurologyUniversity Hospitals Case Medical CenterClevelandUSA
  4. 4.Department of PsychologyEmory UniversityAtlantaUSA
  5. 5.Department of NeurosurgeryStanford UniversityStanfordUSA
  6. 6.VA Medical CenterAtlantaUSA
  7. 7.Depatment of NeurologyEmory UniversityAtlantaUSA

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