... colour channels they possess may underlie a different method of colour processing. We investigated one hypothesis in which the photoreceptors are proposed to act as individual wave-band detectors, interpreting colour as a parallel pattern of photoreceptor activation, rather than a ratiometric comparison...

... photoreceptors and circuits can such measures guide modelling of natural vision in different species and illuminate functional and evolutionary trade-offs. Temporal vision research would benefit from bridging traditions that speak different languages. Towards that goal, I here review studies from the fields...

... system. These include variations in the topography, spectral sensitivity and density of retinal photoreceptors, and changes in the eye's gross anatomy and spectral transmission characteristics. We have characterised visual spectral sensitivity in the murid rodent Rhabdomys pumilio (the four-striped grass...

..., seasonally or ontogenetically. To survive in these variable light habitats, fish visual systems have evolved a suite of mechanisms that modulate spectral sensitivities on a range of timescales. These mechanisms include: (1) optical media that filter light, (2) variations in photoreceptor type and size...

... and polarization properties of the photoreceptors of a migrating nymphalid, Parantica sita . Our findings reveal three spectral classes of photoreceptors including ultraviolet, blue and green receptors. The green receptor class contains three subclasses, which are broad, narrow and double-peaking green receptors...

... of motion vision in P . xuthus to incorporate these polarization findings, and conclude that the photoreceptors likely to form the basis for the putative monopolatic polarization detector are R3 and R4, which respond maximally to horizontally polarized green light. R5–R8, we propose, form a polarization...

...Hiroshi D. Akashi; Pei-Ju Chen; Tokiho Akiyama; Yohey Terai; Motohiro Wakakuwa; Yasunori Takayama; Makoto Tominaga; Kentaro Arikawa ABSTRACT Histamine is the only known neurotransmitter released by arthropod photoreceptors. Synaptic transmission from photoreceptors to second-order neurons...

...David Wilby; Nicholas W. Roberts ABSTRACT Oil droplets are spherical organelles found in the cone photoreceptors of vertebrates. They are generally assumed to focus incident light into the outer segment, and thereby improve light catch because of the droplets' spherical lens-like shape. However...

...Anna Honkanen; Jouni Takalo; Kyösti Heimonen; Mikko Vähäsöyrinki; Matti Weckström Reliable vision in dim light depends on the efficient capture of photons. Moreover, visually guided behaviour requires reliable signals from the photoreceptors to generate appropriate motor reactions. Here, we show...

...Xiaobang Hu; Matthew T. Leming; Michelle A. Whaley; Joseph E. O'Tousa Differential rhodopsin gene expression within specialized R7 photoreceptor cells divides the retinas of Aedes aegypti and Anopheles gambiae mosquitoes into distinct domains. The two species express the rhodopsin orthologs Aaop8...

... sensitivities of the photoreceptors are rather simple, and peak in the ultraviolet, blue and green wavelength regions. The ommatidia have neither perirhabdomal nor fluorescent pigments, which modulate photoreceptor spectral sensitivities in a number of other butterfly species. These features are primitive...

...Gregor Belušič; Primož Pirih; Doekele G. Stavenga SUMMARY The owlfly Libelloides macaronius (Insecta: Neuroptera) has large bipartite eyes of the superposition type. The spatial resolution and sensitivity of the photoreceptor array in the dorsofrontal eye part was studied with optical...

... classes of cones were found (two S-cones, M-cones and L-cones), correlating with the four classes of vertebrate cone pigments. For quantitative estimation of chromophore proportions, we considered mainly rods and M-cones. In four populations, spectra of both photoreceptor types indicated A2 dominance...

..., we studied the developmental trajectory of the photopic visual process in the Nile tilapia. We examined ontogenetic changes in lens transmission, photoreceptor sensitivity and post-receptoral sensitivity, and used these to estimate changes in cone pigment frequency and retinal circuitry. We observed...

...Jason C. Raine; Allison B. Coffin; Craig W. Hawryshyn SUMMARY Thyroid hormones (THs) play a vital role in vertebrate neural development, and, together with the beta isoform of the thyroid hormone receptor (TRβ), the development and differentiation of cone photoreceptors in the vertebrate retina...

... different types of photoreceptors with absorbance maxima in the mid-range of the spectrum, at 480 nm and 520 nm and in the UV at 360 nm. Based on these physiological data colour vision might be possible. In the present study, the ability to discriminate coloured moving stimuli from grey backgrounds...

...-sensitive opsins, whereas UpRh3 is similar to other arthropod UV-sensitive opsins. All three opsins are expressed in each ommatidium, in an opsin-specific pattern. UpRh3 is present only in the R8 photoreceptor cell, whereas UpRh1 and UpRh2 are present in the R1-7 cells, with UpRh1 expression restricted...

...-expression of the opsins of the UV- and B-absorbing type in a subset of photoreceptors, and subfunctionalization of long-wavelength receptors in the distal tier as a result of differential expression of the PgL2 and PgL3 mRNAs. Interestingly, butterflies from the closely related genus Papilio (Papilionidae...

...C. Katti; K. Kempler; M. L. Porter; A. Legg; R. Gonzalez; E. Garcia-Rivera; D. Dugger; B.-A. Battelle SUMMARY A long-standing concept in vision science has held that a single photoreceptor expresses a single type of opsin, the protein component of visual pigment. However, the number of examples...

... thyroid hormone retina degeneration opsin photoreceptor development thyroid hormone receptors deiodinase The retina of salmonid fishes (trout and salmon) contains several analogous classes of cone photoreceptors [short wavelength-sensitive (SWS), medium wavelength-sensitive (MWS) and long...