Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Mechanisms of accommodation and refractive error.

L F Garner

    Ophthalmic & Physiological Optics : the Journal of the British College of Ophthalmic Opticians (Optometrists)
    |January 1, 1983
    PubMed
    Summary

    The classical Helmholtz theory of accommodation is challenged by new findings. Recent studies suggest sympathetic innervation to the ciliary muscle may influence refractive errors.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    History of nursing at Baylor University Medical Center.

    Proceedings (Baylor University. Medical Center)·2005
    Same author

    The Nepal longitudinal study: predicting myopia from the rate of increase in vitreous chamber depth.

    Optometry and vision science : official publication of the American Academy of Optometry·2004
    Same author

    Gradient refractive index of the crystalline lens of the Black Oreo Dory (Allocyttus Niger): comparison of magnetic resonance imaging (MRI) and laser ray-trace methods.

    Vision research·2001
    Same author

    The spherical aberration of the crystalline lens of the human eye.

    Vision research·2001
    Same author

    Prevalence of myopia in Sherpa and Tibetan children in Nepal.

    Optometry and vision science : official publication of the American Academy of Optometry·1999
    Same author

    Radius of curvature of the posterior surface of the cornea.

    Optometry and vision science : official publication of the American Academy of Optometry·1997

    Area of Science:

    • Ophthalmology and Optometry
    • Neuroscience
    • Physiology

    Background:

    • The Helmholtz theory of accommodation, foundational in optometry, posits only parasympathetic innervation of the ciliary muscle and a resting point at optical infinity for emmetropic eyes.
    • The concept of dual sympathetic and parasympathetic innervation of the ciliary muscle has existed since the 19th century.
    • Contemporary research suggests the eye's resting accommodation, or 'dark focus,' is at an intermediate distance, representing a tonus position with minimal autonomic input.

    Purpose of the Study:

    • To re-evaluate the classical theory of accommodation.
    • To explore the potential role of sympathetic innervation in the ciliary muscle.
    • To investigate the implications for the development and correction of refractive errors.

    Main Methods:

    • Review of historical and recent scientific literature on the autonomic innervation of the ciliary muscle.
    • Analysis of studies investigating the 'dark focus' and resting refractive state.
    • Theoretical consideration of sympathetic influence on accommodation and refractive error.

    Main Results:

    • Evidence suggests the resting point of accommodation (dark focus) is not at optical infinity.
    • The tonus position of the ciliary muscle may be influenced by minimal autonomic innervation.
    • A potential role for sympathetic innervation in refractive error development and correction is indicated.

    Conclusions:

    • The classical Helmholtz theory may be incomplete.
    • Sympathetic innervation could play a significant role in ciliary muscle function and refractive error.
    • Further research is warranted to elucidate the complete picture of ciliary muscle innervation.

    Related Experiment Videos