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PubMed · 9267631

A fundamental step-transition in retinal function at low light intensities.

I G Morgan·M K Boelen
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Abstract

There appears to be a fundamental step-transition in retinal function at low light intensities, close to the scotopic-mesopic transition. This step-transition is observed for elements of the retinal dark-light switch, which has been described in the chicken retina. Over the same range of light intensities, there is a step-transition in photoreceptor retinomotor movements and in the coupling of horizontal and All amacrine cells, which suggests a switch in retinal circuitry from rod-processing to cone-processing regimes. A similar step-transition in pineal function suggests that the retinal step-transition signals to the central circadian systems. Finally, this step-transition may also inhibit eye growth, and thus be responsible for the reported diurnal rhythm in eye growth. Disturbances to this step-transition may be the initial cause of disordered eye growth in the form-deprivation myopia paradigm.

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Adaptation, OcularAnimalsDopamineLightLight Signal TransductionMelatoninPineal GlandRetinaVisual PathwaysVisual PerceptionJournal ArticleReview

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BibTeXRIS

I G Morgan, M K Boelen. 1997. A fundamental step-transition in retinal function at low light intensities.. https://doi.org/10.1111/j.1442-9071.1997.tb01762.x

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