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Hansen MJ, Cocherell DE, Cooke SJ, Patrick PH, Sills M, Fangue NA. Behavioural guidance of Chinook salmon smolts: the variable effects of LED spectral wavelength and strobing frequency. CONSERVATION PHYSIOLOGY 2018; 6:coy032. [PMID: 29977564 PMCID: PMC6016652 DOI: 10.1093/conphys/coy032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 05/23/2018] [Accepted: 06/11/2018] [Indexed: 06/08/2023]
Abstract
Exploiting species-specific behavioural responses of fish to light is an increasingly promising technique to reduce the entrainment or impingement of fish that results from the diversion of water for human activities, such as hydropower or irrigation. Whilst there is some evidence that white light can be an effective deterrent for Chinook salmon smolts, the results have been mixed. There is a need to test the response of fish to different spectra and strobing frequencies to improve deterrent performance. We tested the movement and spatial response of groups of four fish to combinations of light-emitting diode (LED) spectra (red, green, blue and white light) during the day and night, and strobing frequencies (constant and 2Hz) during the day, using innovative LED technology intended as a behavioural guidance device for use in the field. Whilst strobing did not alter fish behaviour when compared to constant light, the red light had a repulsive effect during the day, with fish under this treatment spending significantly less time in the half of the arena closest to the behavioural guidance device compared to both the control and blue light. Importantly, this effect disappeared at night, where there were no differences in movement and space use found between spectra. There was some evidence of a potential attractive response of fish to the blue and green light during the day. Under these light treatments, fish spent the highest amount of time closest to the behavioural guidance device. Further tests manipulating the light intensity in the different spectra are needed to verify the mechanistic determinants of the observed behaviours. Results are discussed in reference to the known spectral sensitivities of the cone and rod photopigments in these fish, and further experiments are suggested to better relate the work to mitigating the effects on fish of infrastructure used for hydropower and irrigation.
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Affiliation(s)
- Matthew J Hansen
- Department of Wildlife, Fish and Conservation Biology, University of California, Davis, One Shields Ave, Davis, CA, USA
| | - Dennis E Cocherell
- Department of Wildlife, Fish and Conservation Biology, University of California, Davis, One Shields Ave, Davis, CA, USA
| | - Steven J Cooke
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology, Institute of Environmental Science, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada
| | - Paul H Patrick
- ATET-TECH, Inc., 68 Maxwell Court, Thornhill, Ontario, Canada
| | - Michael Sills
- ATET-TECH, Inc., 68 Maxwell Court, Thornhill, Ontario, Canada
| | - Nann A Fangue
- Department of Wildlife, Fish and Conservation Biology, University of California, Davis, One Shields Ave, Davis, CA, USA
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Maximov V, Maximova E, Damjanović I, Aliper A, Maximov P. Color properties of the motion detectors projecting to the goldfish tectum: II. Selective stimulation of different chromatic types of cones. J Integr Neurosci 2015; 14:31-52. [PMID: 25553912 DOI: 10.1142/s0219635215500053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sensitivity to the sign of contrast of direction-selective (DS) and orientation-selective (OS) ganglion cells (GCs) was investigated with selective stimulation of different chromatic types of cones. It was shown that the DS GCs that were classified with the use of achromatic stimuli as belonging to the ON type responded to selective stimulation of the long-wave cones as the ON type also, while the stimulation of middle-wave or short-wave cones elicited the OFF type responses. Character of the responses of DS GCs of the OFF type was exactly the opposite. OS GCs, which responded to achromatic stimuli as the ON-OFF type, responded to selective stimulation of the long-wave cones as the ON-OFF type as well, responded to middle-wave stimulation as the OFF type and to stimulation of short-wave cones it responded mainly as the ON type. At the same time, under color-selective stimulation, both DS and OS GCs retained the directional and orientation selectivity with the same preferred directions. The results obtained are in favor of the idea that the signals from the different chromatic types of cones are combined in the outer synaptic layer of the retina at the inputs of bipolar cells using sign-inverting and/or sign-conserving synapses, while specific spatial properties of motion detectors are formed in the inner synaptic layer.
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Affiliation(s)
- Vadim Maximov
- Institute for Information Transmission Problems, Russian Academy of Sciences, Bolshoi Karetny Per., 19, Moscow 127994 GSP-4, Russia
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Roberts NW, Porter ML, Cronin TW. The molecular basis of mechanisms underlying polarization vision. Philos Trans R Soc Lond B Biol Sci 2011; 366:627-37. [PMID: 21282166 PMCID: PMC3049014 DOI: 10.1098/rstb.2010.0206] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The underlying mechanisms of polarization sensitivity (PS) have long remained elusive. For rhabdomeric photoreceptors, questions remain over the high levels of PS measured experimentally. In ciliary photoreceptors, and specifically cones, little direct evidence supports any type of mechanism. In order to promote a greater interest in these fundamental aspects of polarization vision, we examined a varied collection of studies linking membrane biochemistry, protein-protein interactions, molecular ordering and membrane phase behaviour. While initially these studies may seem unrelated to polarization vision, a common narrative emerges. A surprising amount of evidence exists demonstrating the importance of protein-protein interactions in both rhabdomeric and ciliary photoreceptors, indicating the possible long-range ordering of the opsin protein for increased PS. Moreover, we extend this direction by considering how such protein paracrystalline organization arises in all cell types from controlled membrane phase behaviour and propose a universal pathway for PS to occur in both rhabdomeric and cone photoreceptors.
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Affiliation(s)
- Nicholas W Roberts
- School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK.
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Spectral sensitivity of single cones in rainbow trout (Oncorhynchus mykiss): A whole-cell voltage clamp study. Vision Res 2010; 50:2055-61. [DOI: 10.1016/j.visres.2010.07.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2010] [Revised: 07/12/2010] [Accepted: 07/17/2010] [Indexed: 11/20/2022]
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5
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Wang FY, Yan HY, Chen JSC, Wang TY, Wang D. Adaptation of visual spectra and opsin genes in seabreams. Vision Res 2009; 49:1860-8. [DOI: 10.1016/j.visres.2009.04.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 04/27/2009] [Accepted: 04/27/2009] [Indexed: 10/20/2022]
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Kinoshita M, Ito E. Roles of periventricular neurons in retinotectal transmission in the optic tectum. Prog Neurobiol 2006; 79:112-21. [PMID: 16901616 DOI: 10.1016/j.pneurobio.2006.06.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2006] [Revised: 06/16/2006] [Accepted: 06/20/2006] [Indexed: 10/24/2022]
Abstract
The midbrain roof is a retinorecipient region referred to as the optic tectum in lower vertebrates, and the superior colliculus in mammals. The retinal fibers projecting to the tectum transmit visual information to tectal retinorecipient neurons. Periventricular neurons are a subtype of these neurons that have their somata in the deepest layer of the teleostean tectum and apical dendrites ramifying at more superficial layers consisting of retinal fibers. The retinotectal synapses between the retinal fibers and periventricular neurons are glutamatergic, and ionotropic glutamate receptors mediate the transmission in these synapses. This transmission involves long-term potentiation, and is modulated by hormone action. Visual information processed in the periventricular neurons is transmitted to adjacent tectal cells and target nuclei of periventricular neuron axonal branches, some of which relay the visual information to other brain areas controlling behavior. We demonstrated that periventricular neurons play a principal role in visual information processing in the teleostean optic tectum; the effects of tectal output on behavior is discussed also in the present review.
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Affiliation(s)
- Masae Kinoshita
- Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan
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Lyng EM, Lyons-Alcantara M, Olwell P, Shuilleabháin SN, Seymour C, Cottell DC, Mothersill C. Ionizing radiation induces a stress response in primary cultures of rainbow trout skin. Radiat Res 2004; 162:226-32. [PMID: 15387151 DOI: 10.1667/rr3216] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Fish skin is very vulnerable to damage from physical and chemical pollutants because it is in direct contact with the aquatic environment. In this study, the effect of gamma radiation on primary cultures of rainbow trout skin was investigated. Primary cultures containing two cell types, epidermal cells and goblet mucous cells, were exposed to doses ranging from 0.5-15 Gy 60Co gamma radiation. Expression of PCNA, c-myc and BCL2 was investigated as well as growth and levels of apoptosis and necrosis. Morphological and functional changes were also studied. The irradiated cultures showed evidence of a dose-dependent increase in necrosis and enhanced proliferation as well as morphological damage. In addition, mucous cell area was found to decrease significantly after irradiation. The study shows the value of these primary cultures as in vitro models for studying radiation effects. They provide an effective alternative to whole-animal exposures for radiation risk assessment.
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Affiliation(s)
- E M Lyng
- Radiation and Environmental Science Centre, Dublin Institute of Technology, Kevin Street, Dublin 8, Ireland.
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Allison WT, Dann SG, Helvik JV, Bradley C, Moyer HD, Hawryshyn CW. Ontogeny of ultraviolet-sensitive cones in the retina of rainbow trout (Oncorhynchus mykiss). J Comp Neurol 2003; 461:294-306. [PMID: 12746869 DOI: 10.1002/cne.10682] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In order to facilitate emerging models of retinal development, we developed electroretinogram and in situ hybridization protocols to examine the ontogeny of photoreceptors in the retina of a land-locked salmonid, the rainbow trout (Oncorhynchus mykiss). We cloned cDNA fragments corresponding to the rod opsin and each of the four cone opsin gene families, which we utilized to produce riboprobes. We established the specificity of the in situ hybridization protocol by examining subcellular signal localization and through double-labeling experiments. We confirm the assumption that the accessory corner cones in the square mosaic are the ultraviolet wavelength-sensitive (UVS) cone photoreceptor (i.e., they express an SWS1 opsin) and observed UVS cones throughout the retina of small trout. Larger fish have a decrease in sensitivity to short wavelength light stimuli and the distribution of UVS cones in the mature retina is limited to the dorsal-temporal quadrant. These larger fish also possess differentiated UVS cones in the peripheral germinal zone (PGZ), including within areas peripheral to mature retina lacking UVS cones. These data are consistent with the loss of putative UVS cones from the PGZ of a migratory salmonid of another genus, and thus the disappearance of UVS cones appears to be general to the Family Salmonidae, regardless of life history strategy. The generation, differentiation, and subsequent loss of UVS cones in the smolt PGZ is a dramatic example of the supposition that the mechanisms of PGZ development recapitulate the retinal embryogenesis of that species.
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Affiliation(s)
- W Ted Allison
- Department of Biology, University of Victoria, Victoria, British Columbia V8W 3N5, Canada
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9
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Abstract
Several studies have indicated that the rainbow trout (Oncorhynchus mykiss) loses ultraviolet (UV) sensitivity and the associated UV-sensitive corner cones when the animal transforms from a small (parr) juvenile to a larger, silver-coloured, smolt. Similar changes supposedly take place when parr juveniles are treated with thyroid hormone (T(4)) or retinoic acid. In contrast to previous investigations, this study shows that parr juveniles lack corner cones throughout the lower half of the ventral retina, suggesting that corner cones cease to be incorporated into the ventral retina some time after hatching. This uneven incorporation of corner cones across the retina, when combined with retinal growth, creates a progressively smaller area of lower retina occupied by corner cones. Because in previous studies, the stimulating illumination was directed primarily at the ventral retina, the reported age-dependent changes in UV or polarization sensitivities can be explained by differences in the area of corner cones that was illuminated, and not necessarily by a loss of corner cones. This study also shows: (1) that the double cones from non-ventral mosaics of parr rainbow trout may change in cross-sectional shape, altering the mosaic formation from a square to a row, (2) the existence of a 'pure' (non-changing) square mosaic in the ventral retina, and (3) a potential method, based on differential staining of cone nuclei, to classify paired cones into double or twin cones.
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Affiliation(s)
- I N Flamarique
- Simon Fraser University, Department of Biological Sciences, 8888 University Drive, BC, V5A 1S6, Burnaby, Canada.
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Parkyn DC, Hawryshyn CW. Ethambutol affects the spectral and polarisation sensitivity of on-responses in the optic nerve of rainbow trout. Vision Res 2001; 39:4145-51. [PMID: 10755152 DOI: 10.1016/s0042-6989(99)00144-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Juvenile rainbow trout (Oncorhynchus mykiss) were given ethambutol (900 mg kg-1 body mass per day) for 4 weeks to examine its effects on vision. Using multi-unit recording from the optic nerve, spectral sensitivity of the on-responses were significantly affected in two regions, 340-440 nm and 600-660 nm. Off-responses were statistically unaffected. Changes in sensitivity to polarised light were also observed with on-responses to vertically-polarized light decreasing relative to horizontally-polarised light. In contrast, off-responses were less affected. The treatment effects were attributed to changes in the relative contribution of the photoreceptor channels as recorded at the level of the optic nerve.
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Affiliation(s)
- D C Parkyn
- Department of Biology, University of Victoria, BC, Canada
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Parkyn DC, Hawryshyn CW. Spectral and ultraviolet-polarisation sensitivity in juvenile salmonids: a comparative analysis using electrophysiology. J Exp Biol 2000; 203:1173-91. [PMID: 10708638 DOI: 10.1242/jeb.203.7.1173] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Spectral and polarisation sensitivity were compared among juvenile (parr) rainbow trout (Oncorhynchus mykiss), steelhead (O. mykiss), cutthroat trout (O. clarki clarki), kokanee (O. nerka) and brook char (Salvelinus fontinalis) using multi-unit recording from the optic nerve. Although reared under the same conditions, differences in photopic spectral sensitivity were evident. Specifically, ON-responses were co-dominated by L- and M-cone mechanisms in all fish except O. nerka, consistent with an M-cone mechanism sensitivity. The sensitivity of OFF-responses was dominated by the M-cone mechanism for all fish, but O. mykiss appeared to show an additional contribution from the L-cone mechanism. Using chromatic adaptation, an independent ultraviolet-sensitive mechanism is described for the first time for the salmonid genus Salvelinus. In addition, this ultraviolet-cone mechanism was present in the members of the genus Oncorhynchus that were examined. Thus, ultraviolet sensitivity appears to be common to the major extant clades of the subfamily Salmoninae. All species showed differential sensitivity to both vertical and horizontal linearly polarised light. This sensitivity differed between ON- and OFF-responses. The ON-responses were maximally sensitive to both vertically and horizontally polarised light, whereas the OFF-responses displayed maximal sensitivity to horizontally polarised light in all species, with reduced sensitivity to vertically polarised light compared with ON-responses. Because of the similarity in the physiological characteristics of polarisation sensitivity among the salmonid species examined, no relationship between the degree of migratory tendency and the ability to detect polarised light could be identified.
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Affiliation(s)
- D C Parkyn
- Department of Biology, University of Victoria, PO Box 3020, STN CSC, Victoria, British Columbia, Canada V8W 3N5.
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McDonald CG, Hawryshyn CW. Latencies and discharge patterns of color-opponent neurons in the rainbow trout optic tectum. Vision Res 1999; 39:2795-9. [PMID: 10492810 DOI: 10.1016/s0042-6989(99)00058-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Although color-opponent neurons appear to subserve color vision, precisely how these cells encode hue is still not clear. Single-unit, extracellular recordings from the rainbow trout optic tectum were made in order to examine the possible role of action potential timing in coding chromatic stimuli. We found that color-opponent units can exhibit differences in response latency which are a function of wavelength and response sign, with the OFF response exhibiting the shorter response latency. We also found that units often responded with spike bursts characterized by early and late spikes separated by a silent period, with the relative proportion of early and late spikes varying as a function of wavelength. This type of discharge pattern appears to be a result of inhibitory, color-opponent processes. We suggest that complete inhibition of early spikes may be the mechanism underlying the observed latency differences. These findings suggest a role for action potential patterning in coding chromatic stimuli.
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Affiliation(s)
- C G McDonald
- Department of Biology, University of Victoria, B.C., Canada
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Bisazza A. Sexual selection constrained by internal fertilization in the livebearing fish Xenotoca eiseni. Anim Behav 1997; 54:1347-55. [PMID: 9521792 DOI: 10.1006/anbe.1997.0539] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fish of the family Goodeidae have an advanced form of viviparity but males lack a specialized copulatory organ. Goodeids show reduced sexual-size dimorphism compared with the other livebearing families of the order Cyprinodontiformes. I investigated some mechanisms of sexual selection acting on body size in the goodeid fish Xenotoca eiseni. Both males and females strongly prefer mates of their own size. Comparison of mating activities in pairs with various degrees of size difference between males and females showed that matched pairs copulated more successfully. Similar mate preference in the two sexes thus appears to be the consequence of the primitive method of internal fertilization that requires the partners to be exactly synchronized during sperm transfer. Competition for access to a female was intense and body size determined the hierarchy in a small group. However, unless the size of the female was close to that of the dominant male, assortative mate preferences prevailed and the large-male advantage in competition was offset. Reduced size dimorphism in X. eiseni and in other goodeids may be explained by constraints on the action of sexual selection imposed by the need for effective fertilization.Copyright 1997 The Association for the Study of Animal BehaviourCopyright 1997The Association for the Study of Animal Behaviour.
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Affiliation(s)
- A Bisazza
- Dipartimento di Psicologia Generale, Università di Padova
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Wubbels RJ, Schellart NA. Neuronal encoding of sound direction in the auditory midbrain of the rainbow trout. J Neurophysiol 1997; 77:3060-74. [PMID: 9212257 DOI: 10.1152/jn.1997.77.6.3060] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Acoustical stimulation causes displacement of the sensory hair cells relative to the otoliths of the fish inner ear. The swimbladder, transforming the acoustical pressure component into displacement, also contributes to the displacement of the hair cells. Together, this (generally) yields elliptical displacement orbits. Alternative mechanisms of fish directional hearing are proposed by the phase model, which requires a temporal neuronal code, and by the orbit model, which requires a spike density code. We investigated whether the directional selective response of auditory neurons in the midbrain torus semicircularis (TS; homologous to the inferior colliculus) is based on spike density and/or temporal encoding. Rainbow trout were mounted on top of a vibrating table that was driven in the horizontal plane to simulate sound source direction. Rectilinear and elliptical (or circular) motion was applied at 172 Hz. Generally, responses to rectilinear and elliptical/circular stimuli (irrespective of direction of revolution) were the same. The response of auditory neurons was either directionally selective (DS units, n = 85) or not (non-DS units, n = 106). The average spontaneous discharge rate of DS units was less than that of non-DS units. Most DS units (70%) had spontaneous activities < 1 spike per second. Response latencies (mode at 18 ms) were similar for both types of units. The response of DS units is transient (19%), sustained (34%), or mixed (47%). The response of 75% of the DS units synchronized to stimulus frequency, whereas just 23% of the non-DS responses did. Synchronized responses were measured at stimulus amplitudes as low as 0.5 nm (at 172 Hz), which is much lower than for auditory neurons in the medulla of the trout, suggesting strong convergence of VIIIth nerve input. The instant of firing of 42% of the units was independent of stimulus direction (shift <15 degrees), but for the other units, a direction dependent phase shift was observed. In the medial TS spatial tuning of DS units is in the rostrocaudal direction, whereas in the lateral TS all preferred directions are present. On average, medial DS units have a broader directional selectivity range, are less often synchronized, and show a smaller shift of the instant of firing as a function of stimulus direction than lateral DS units. DS response characteristics are discussed in relation to different hypotheses. We conclude that the results are more in favor of the phase model.
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Affiliation(s)
- R J Wubbels
- Laboratory of Medical Physics and Informatics, University of Amsterdam, Academic Medical Center, The Netherlands
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Browman HI, Hawryshyn CW. The developmental trajectory of ultraviolet photosensitivity in rainbow trout is altered by thyroxine. Vision Res 1994; 34:1397-406. [PMID: 8023449 DOI: 10.1016/0042-6989(94)90139-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Small (< 30 g) juvenile rainbow trout (Oncorhynchus mykiss) possess retinal photoreceptor mechanisms sensitive to ultraviolet (UV), short (S), middle (M), and long (L) wavelengths. During normal development, UV photosensitivity is lost progressively until, by approx. 60 g, individuals are no longer sensitive in the UV. This shift in spectral sensitivity is associated with the disappearance of small accessory corner cones (ACCs) from the retinal photoreceptor cell mosaic: the UV cone mechanism is lost. Exposing small (< 16 g) rainbow trout to the thyroid hormone thyroxine (T4) for a period of 6 weeks induced a precocial loss of the UV cone mechanism that was indistinguishable from the events that occur during normal development. Six weeks after termination of hormone treatment, the same individuals that had lost their UV photosensitivity after exposure to T4 once again possessed a peak in spectral sensitivity at 360 nm. ACCs had reappeared in the retinae of these fish. After 6 weeks of exposure to thyroxine, large (> 90 g) juvenile rainbow trout, which had lost their UV photoreceptor mechanism during normal development, were once again UV photosensitive and ACCs were found in their retinae. These results imply that the UV photoreceptor mechanism, although lost at one point during development, can reappear at another time during the life history of the same individual. Thyroid hormones appear to be involved in both the loss and reappearance of UV photosensitivity.
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Affiliation(s)
- H I Browman
- Department of Biology, University of Victoria, British Columbia, Canada
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