Pharmacological treatment effects on eye movement control
James L Reilly1, Rebekka Lencer, Jeffrey R Bishop
1Center for Cognitive Medicine, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL 60612, USA. jreilly@psych.uic.edu
Brain and Cognition
|November 26, 2008
Summary
Eye movements are sensitive to many medications, reflecting central nervous system effects. This review highlights their potential as biomarkers for drug development and personalized treatment in clinical disorders.
Area of Science:
- Neuroscience
- Pharmacology
- Ophthalmology
Background:
- Eye movement paradigms are increasingly used to assess brain function in clinical disorders.
- Understanding medication effects on eye movements is crucial for differentiating disease from drug impacts.
- Oculomotor function can reveal neurochemical system involvement and serve as biomarkers for drug effects.
Purpose of the Study:
- To review pharmacological treatment effects on eye movements in healthy individuals and clinical populations.
- To establish the sensitivity of eye movements to various drug classes.
- To explore the utility of eye movements as biomarkers in pharmacodynamic and pharmacogenetic studies.
Main Methods:
- Systematic review of studies on pharmacologic effects on eye movements.
- Analysis of data from healthy individuals and patients with clinical disorders.
- Examination of oculomotor measures like saccade and smooth pursuit velocity.
Main Results:
- Most drug classes (e.g., benzodiazepines, antipsychotics) decrease saccade and smooth pursuit velocity, reflecting sedation.
- Oculomotor changes are often dose-dependent and more sensitive than other measures.
- Some agents (e.g., SSRIs, stimulants) do not impair, and may enhance, oculomotor performance.
Conclusions:
- Eye movements are sensitive indicators of drug effects on sensorimotor and cognitive processing.
- Medication impacts must be considered when interpreting oculomotor data in clinical populations.
- Eye movement measurements show promise as biomarkers for drug development and personalized medicine.
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