Licht-im-Terrarium: Literaturdatenbank
Licht-im-Terrarium: Literaturdatenbank |
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Jacobs, G. H., Fenwick, J. A., & Williams, G. A. (2001). Cone-based vision of rats for ultraviolet and visible lights. The Journal of Experimental Biology, 204, 2439–2446. Added by: Sarina (2010-09-18 15:26:01) |
| Resource type: Journal Article BibTeX citation key: Jacobs2001 View all bibliographic details  |
Categories: Englisch = English Keywords: Farbsehen = Color Vision, Säugetiere = Mammals, Ultraviolett = Ultraviolet Creators: Fenwick, Jacobs, Williams Collection: The Journal of Experimental Biology |
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| Abstract |
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Rats (Rattus norvegicus) have two classes of cone, one containing an ultraviolet (UV)-sensitive photopigment and the other housing a pigment maximally sensitive in the middle (M) wavelengths of the visible spectrum. The manner in which signals from these two cone types contribute to rat vision was investigated through recordings of a gross electrical potential (the electroretinogram, ERG) and behavioral discrimination tests. Spectral sensitivity functions obtained from both types of measurement indicate clear contributions from each of the cone classes, but there is a marked enhancement of the relative sensitivity to UV light in the behavioral index; for instance, under some photopic test conditions, rats are approximately equally sensitive to middle-wavelength and UV lights. In adaptation tests, thresholds for UV and M lights were found to be differentially elevated in the presence of chromatic adapting backgrounds, thus providing the possibility that signals from the two cones could be used by the rat visual system to support color discriminations. Evidence of dichromatic color vision in the rat was subsequently obtained from tests of wavelength discrimination. Key words: rat, Rattus norvegicus, vision, cones, spectral sensitivity, color vision, ultraviolet sensitivity, electroretinogram. Added by: Sarina |