Related Experiment Video
Updated: Aug 16, 2026
04:43
Visualizing Visual Adaptation
Published on: April 24, 2017
Temporal vision adaptation and restoration in achromatopsia
Ayelet McKyton1, Atira Bick1, Deena Elul1,2
1fMRI Unit, Department of Neurology, Hadassah Medical Center and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
Iscience
|August 15, 2026
Summary
People with achromatopsia (ACHM), a cone dysfunction, adapt their temporal vision. Gene therapy shows promise for restoring temporal resolution, especially when initiated in childhood.
Area of Science:
- Ophthalmology
- Neuroscience
- Genetics
Background:
- Temporal vision relies on cone function, which is impaired in achromatopsia (ACHM).
- ACHM patients exhibit lifelong rod reliance, impacting their visual processing.
- Understanding temporal vision adaptation in ACHM is crucial for assessing treatment efficacy.
Purpose of the Study:
- To investigate visual system adaptation to slowed input in complete CNGA3/B3 achromatopsia (ACHM).
- To evaluate the impact of gene therapy on temporal resolution in ACHM patients.
- To compare temporal vision under photopic and scotopic conditions in controls and ACHM patients.
Main Methods:
- Assessed temporal contrast sensitivity function (tCSF) including maximal sensitivity, peak frequency, and flicker fusion frequency (FFF).
- Measured temporal vision in 8 controls, 7 untreated ACHM patients, and 4 treated ACHM patients.
- Compared results under both photopic (cone-driven) and scotopic (rod-driven) conditions.
Main Results:
- Controls demonstrated superior temporal vision under photopic conditions compared to scotopic.
- Untreated ACHM patients showed photopic sensitivity and FFF akin to controls' scotopic values.
- ACHM patients exhibited peak temporal tuning resembling controls' photopic values, suggesting adaptation.
Conclusions:
- The visual system demonstrates adaptive peak temporal tuning even with rod-dominant input in ACHM.
- Gene therapy shows potential for restoring temporal resolution in ACHM.
- Early intervention with gene therapy, particularly in childhood, may be key to fully restoring temporal visual function.
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