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

Accommodation, refractive error and eye growth in chickens.

F Schaeffel1, A Glasser, H C Howland

  • 1Section of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853.

Vision Research
|January 1, 1988
PubMed
Summary

Chickens wearing defocusing lenses showed adaptive eye growth. Negative lenses increased posterior nodal distance, while positive lenses decreased it, suggesting a feedback system regulates eye development.

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

[Prevention of myopia].

Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft·2019
Same author

[Comparative analysis of light sensitivity, depth and motion perception in animals and humans].

Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft·2017
Same author

[Visual performance of animals and humans in comparison].

Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft·2017
Same author

[Biological mechanisms of myopia].

Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft·2016
Same author

[Current recommendations for deceleration of myopia progression].

Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft·2016
Same author

[Clinical risk factors for progressive myopia].

Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft·2012

Area of Science:

  • Ophthalmology
  • Animal models
  • Developmental biology

Background:

  • Animal models are crucial for understanding eye growth regulation.
  • Defocusing lenses can induce adaptive changes in refractive state and eye dimensions.
  • Previous studies suggest a feedback mechanism controls eye development.

Purpose of the Study:

  • To investigate the impact of sustained optical defocus on eye growth in chickens.
  • To determine if induced refractive shifts correlate with changes in posterior nodal distance (PND).
  • To explore the role of a feedback system in regulating ocular development.

Main Methods:

  • Chickens were fitted with hoods wearing lenses of varying powers to induce optical defocus.
  • Infrared (IR) photoretinoscopy confirmed the ability of chickens to maintain retinal focus.

Related Experiment Videos

  • Posterior nodal distance (PND) was precisely measured in excised eyes using a sensitive technique.

    • Main Results:

    • Wearing lenses induced a refractive shift in the direction that compensated for the imposed defocus.
    • Eyes treated with negative lenses exhibited an increased PND compared to those treated with positive lenses.
    • These changes in PND were independent of corneal curvature, suggesting axial elongation or shortening.

    Conclusions:

    • The results support a closed-loop feedback system regulating eye growth in response to optical defocus.
    • Sustained defocus, particularly with negative lenses, promotes axial elongation.
    • This study provides insights into the mechanisms of emmetropization and potential therapeutic targets for refractive errors.