1
|
Blary CLM, Duriez O, Bonadonna F, Mitkus M, Caro SP, Besnard A, Potier S. Low achromatic contrast sensitivity in birds: a common attribute shared by many phylogenetic orders. J Exp Biol 2024; 227:jeb246342. [PMID: 38099472 DOI: 10.1242/jeb.246342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 12/06/2023] [Indexed: 02/10/2024]
Abstract
Vision is an important sensory modality in birds, which can outperform other vertebrates in some visual abilities. However, sensitivity to achromatic contrasts - the ability to discern luminance difference between two objects or an object and its background - has been shown to be lower in birds compared with other vertebrates. We conducted a comparative study to evaluate the achromatic contrast sensitivity of 32 bird species from 12 orders using the optocollic reflex technique. We then performed an analysis to test for potential variability in contrast sensitivity depending on the corneal diameter to the axial length ratio, a proxy of the retinal image brightness. To account for potential influences of evolutionary relatedness, we included phylogeny in our analyses. We found a low achromatic contrast sensitivity for all avian species studied compared with other vertebrates (except small mammals), with high variability between species. This variability is partly related to phylogeny but appears to be independent of image brightness.
Collapse
Affiliation(s)
- Constance L M Blary
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, 34293 Montpellier, France
- Agence de l'environnement et de la Maîtrise de l'Energie 20, 49004 Angers Cedex 01, France
| | - Olivier Duriez
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, 34293 Montpellier, France
| | | | - Mindaugas Mitkus
- Institute of Biosciences, Life Sciences Center, Vilnius University, 10257 Vilnius, Lithuania
| | - Samuel P Caro
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, 34293 Montpellier, France
| | - Aurélien Besnard
- CEFE, Univ Montpellier, CNRS, EPHE PSL University, IRD, 34293 Montpellier, France
| | - Simon Potier
- Lund Vision Group, Department of Biology, Lund University, Lund 22362, Sweden
- Les Ailes de l'Urga, 27320 Marcilly la Campagne, France
| |
Collapse
|
2
|
Tkatchenko TV, Tkatchenko AV. Genome-wide analysis of retinal transcriptome reveals common genetic network underlying perception of contrast and optical defocus detection. BMC Med Genomics 2021; 14:153. [PMID: 34107987 PMCID: PMC8190860 DOI: 10.1186/s12920-021-01005-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 06/04/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Refractive eye development is regulated by optical defocus in a process of emmetropization. Excessive exposure to negative optical defocus often leads to the development of myopia. However, it is still largely unknown how optical defocus is detected by the retina. METHODS Here, we used genome-wide RNA-sequencing to conduct analysis of the retinal gene expression network underlying contrast perception and refractive eye development. RESULTS We report that the genetic network subserving contrast perception plays an important role in optical defocus detection and emmetropization. Our results demonstrate an interaction between contrast perception, the retinal circadian clock pathway and the signaling pathway underlying optical defocus detection. We also observe that the relative majority of genes causing human myopia are involved in the processing of optical defocus. CONCLUSIONS Together, our results support the hypothesis that optical defocus is perceived by the retina using contrast as a proxy and provide new insights into molecular signaling underlying refractive eye development.
Collapse
Affiliation(s)
| | - Andrei V. Tkatchenko
- Department of Ophthalmology, Columbia University, New York, NY USA
- Department of Pathology and Cell Biology, Columbia University, New York, NY USA
- Edward S. Harkness Eye Institute, Research Annex Room 415, 635 W. 165th Street, New York, NY 10032 USA
| |
Collapse
|
3
|
Jnawali A, Lin X, Patel NB, Frishman LJ, Ostrin LA. Retinal ganglion cell ablation in guinea pigs. Exp Eye Res 2020; 202:108339. [PMID: 33127343 DOI: 10.1016/j.exer.2020.108339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/19/2020] [Accepted: 10/24/2020] [Indexed: 10/23/2022]
Abstract
Guinea pigs are a common model of human ocular conditions; however, their visual function has not been fully characterized. The purpose of this study was to determine the contributions of retinal ganglion cells to structural and functional measures in guinea pigs. Healthy adult guinea pigs (n = 12) underwent unilateral optic nerve crush. Retinal structure was assessed with spectral domain optical coherence tomography (OCT), and thickness of the ganglion cell/nerve fiber layer (GC/NFL) was determined. Visual function was assessed with optomotor tracking of a drifting grating and light adapted electroretinograms (ERGs). From flash ERGs, a-wave, b-wave, oscillatory potentials (OPs), and photopic negative response (PhNR) were analyzed. From pattern ERGs, N1P1 and P1N2 were analyzed. Histological studies were done at various time points for ganglion cell quantification. Optomotor tracking was absent in optic nerve crush eyes following optic nerve crush. Significant thinning of the GC/NFL was evident four weeks following the crush. Flash ERGs revealed a significant reduction in the OP1 amplitude two weeks following crush (P < 0.01) and in the PhNR amplitude six weeks following crush (P < 0.01). There were no significant changes in a-wave, b-wave, or pattern ERG responses (P > 0.05 for all). In vivo OCT imaging showed progressive thinning of inner retinal layers. Ganglion cell density, quantified histologically, was significantly reduced by 75% in the optic nerve crush eye compared to the control eye at four weeks following crush. These findings indicate that retinal ganglion cells contribute to the PhNR and OP1 components of the full field flash ERG, but not significantly to the pattern ERG in guinea pigs. This study demonstrates that OCT imaging and full field flash ERGs are valuable in assessing retinal ganglion cell loss in vivo in guinea pigs and will help to further establish the guinea pig as a model of human ocular pathologies.
Collapse
Affiliation(s)
- Ashutosh Jnawali
- College of Optometry University of Houston, 4901 Calhoun Rd, Houston, TX, 77096, USA.
| | - Xiao Lin
- College of Optometry University of Houston, 4901 Calhoun Rd, Houston, TX, 77096, USA.
| | - Nimesh B Patel
- College of Optometry University of Houston, 4901 Calhoun Rd, Houston, TX, 77096, USA.
| | - Laura J Frishman
- College of Optometry University of Houston, 4901 Calhoun Rd, Houston, TX, 77096, USA.
| | - Lisa A Ostrin
- College of Optometry University of Houston, 4901 Calhoun Rd, Houston, TX, 77096, USA.
| |
Collapse
|
4
|
Cheng N, Pagtalunan E, Abushaibah A, Naidu J, Stell WK, Rho JM, Sauvé Y. Atypical visual processing in a mouse model of autism. Sci Rep 2020; 10:12390. [PMID: 32709898 PMCID: PMC7381655 DOI: 10.1038/s41598-020-68589-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 06/15/2020] [Indexed: 12/03/2022] Open
Abstract
Human social cognition relies heavily on the processing of various visual cues, such as eye contact and facial expressions. Atypical visual perception and integration have been recognized as key phenotypes in individuals diagnosed with autism spectrum disorder (ASD), and may potentially contribute to impediments in normal social development, a hallmark of ASD. Meanwhile, increasing studies on visual function in ASD have pointed to detail-oriented perception, which has been hypothesized to result from heightened response to information of high spatial frequency. However, mixed results of human studies have led to much debate, and investigations using animal models have been limited. Here, using BTBR mice as a model of idiopathic ASD, we assessed retinal stimulus processing by full-field electroretinogram and found impaired photoreceptor function and retina-based alterations mostly in the cone pathway. Using the optokinetic reflex to evaluate visual function, we observed robustly enhanced visual response to finer spatial details and more subtle contrasts at only higher spatial frequencies in the BTBR mice, under both photopic and scotopic conditions. These behavioral results, which are similar to findings in a subset of ASD patients, indicate a bias toward processing information of high spatial frequencies. Together, these findings also suggest that, while enhancement of visual behaviors under both photopic and scotopic conditions might be due to alterations in visual processing common to both rod and cone pathways, these mechanisms are probably downstream of photoreceptor function.
Collapse
Affiliation(s)
- Ning Cheng
- Alberta Children's Hospital Research Institute (ACHRI), Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada.
| | - Eden Pagtalunan
- Alberta Children's Hospital Research Institute (ACHRI), Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada.,O'Brien Centre for the Bachelor of Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Abdulrahman Abushaibah
- Alberta Children's Hospital Research Institute (ACHRI), Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada.,O'Brien Centre for the Bachelor of Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Jessica Naidu
- Alberta Children's Hospital Research Institute (ACHRI), Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada.,O'Brien Centre for the Bachelor of Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - William K Stell
- Department of Cell Biology and Anatomy, Alberta Children's Hospital Research Institute and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Jong M Rho
- Alberta Children's Hospital Research Institute (ACHRI), Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada.,Departments of Neurosciences and Pediatrics, University of California San Diego, Rady Children's Hospital, San Diego, CA, USA
| | - Yves Sauvé
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, AB, Canada.,Department of Physiology, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
5
|
Quantification of Changes in Visual Function During Disease Development in a Mouse Model of Pigmentary Glaucoma. J Glaucoma 2019; 27:828-841. [PMID: 30001268 DOI: 10.1097/ijg.0000000000001024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE We investigated the relationship between visual parameters that are commonly affected during glaucomatous disease progression with functional measures of retina physiology using electroretinography and behavioral measures of visual function in a mouse model of glaucoma. Electroretinogram components measuring retinal ganglion cell (RGC) responses were determined using the non-invasive Ganzfeld flash electroretinography (fERG) to assess RGC loss in a mouse model of glaucoma. METHODS Intraocular pressure (IOP), behaviorally assessed measures of visual function, namely visual acuity and contrast sensitivity as well as fERG responses were recorded in 4- and 11-month-old male DBA/2 mice. Scotopic threshold response (STR) and photopic negative response components as well as oscillatory potentials (OPs) were isolated from fERG responses and correlated with IOP, optomotor reflex measurements, and RGC counts. RESULTS The 11-month-old DBA/2 mice had significantly elevated IOP, reduced visual performance, as assessed behaviorally, significant RGC loss, deficits in standardized fERG responses, reduced STRs, and differences in OP amplitudes and latencies, when compared with 4-month-old mice of the same strain. STRs and OPs correlated with some visual and physiological parameters. In addition, elevated IOP and RGC loss correlated positively with measures of visual function, specifically with surrogate measures of RGC function derived from fERG. CONCLUSIONS Our data suggest that RGC function as well as interactions of RGCs with other retinal cell types is impaired during glaucoma. In addition, a later OP wavelet denoted as OP4 in this study was identified as a very reproducible indicator of loss of visual function in the glaucoma mouse model.
Collapse
|
6
|
Yang GQ, Chen T, Tao Y, Zhang ZM. Recent advances in the dark adaptation investigations. Int J Ophthalmol 2015; 8:1245-52. [PMID: 26682182 DOI: 10.3980/j.issn.2222-3959.2015.06.31] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 01/28/2015] [Indexed: 12/15/2022] Open
Abstract
Dark adaptation is a highly sensitive neural function and may be the first symptom of many status including the physiologic and pathologic entity, suggesting that it could be instrumental for diagnose. However, shortcomings such as the lack of standardized parameters, the long duration of examination, and subjective randomness would substantially impede the use of dark adaptation in clinical work. In this review we summarize the recent research about the dark adaptation, including two visual cycles-canonical and cone-specific visual cycle, affecting factors and the methods for measuring dark adaptation. In the opinions of authors, intensive investigations are needed to be done for the widely use of this significant visual function in clinic.
Collapse
Affiliation(s)
- Guo-Qing Yang
- Department of Clinical Aerospace Medicine, the Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Tao Chen
- Department of Clinical Aerospace Medicine, the Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Ye Tao
- Department of Ophthalmology, Beidaihe Hospital of PLA, Beidaihe 066100, Hebei Province, China
| | - Zuo-Ming Zhang
- Department of Clinical Aerospace Medicine, the Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| |
Collapse
|
7
|
Psychophysical testing in rodent models of glaucomatous optic neuropathy. Exp Eye Res 2015; 141:154-63. [PMID: 26144667 DOI: 10.1016/j.exer.2015.06.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 06/08/2015] [Accepted: 06/29/2015] [Indexed: 12/14/2022]
Abstract
Processing of visual information begins in the retina, with photoreceptors converting light stimuli into neural signals. Ultimately, signals are transmitted to the brain through signaling networks formed by interneurons, namely bipolar, horizontal and amacrine cells providing input to retinal ganglion cells (RGCs), which form the optic nerve with their axons. As part of the chronic nature of glaucomatous optic neuropathy, the increasing and irreversible damage and ultimately loss of neurons, RGCs in particular, occurs following progressive damage to the optic nerve head (ONH), eventually resulting in visual impairment and visual field loss. There are two behavioral assays that are typically used to assess visual deficits in glaucoma rodent models, the visual water task and the optokinetic drum. The visual water task can assess an animal's ability to distinguish grating patterns that are associated with an escape from water. The optokinetic drum relies on the optomotor response, a reflex turning of the head and neck in the direction of the visual stimuli, which usually consists of rotating black and white gratings. This reflex is a physiological response critical for keeping the image stable on the retina. Driven initially by the neuronal input from direction-selective RGCs, this reflex is comprised of a number of critical sensory and motor elements. In the presence of repeatable and defined stimuli, this reflex is extremely well suited to analyze subtle changes in the circuitry and performance of retinal neurons. Increasing the cycles of these alternating gratings per degree, or gradually reducing the contrast of the visual stimuli, threshold levels can be determined at which the animal is no longer tracking the stimuli, and thereby visual function of the animal can be determined non-invasively. Integrating these assays into an array of outcome measures that determine multiple aspects of visual function is a central goal in vision research and can be realized, for example, by the combination of measuring optomotor reflex function with electroretinograms (ERGs) and optical coherence tomography (OCT) of the retina. These structure-function correlations in vivo are urgently needed to identify disease mechanisms as potential new targets for drug development. Such a combination of the experimental assessment of the optokinetic reflex (OKR) or optomotor response (OMR) with other measures of retinal structure and function is especially valuable for research on GON. The chronic progression of the disease is characterized by a gradual decrease in function accompanied by a concomitant increase in structural damage to the retina, therefore the assessment of subtle changes is key to determining the success of novel intervention strategies.
Collapse
|
8
|
Stimulus motion improves spatial contrast sensitivity in budgerigars (Melopsittacus undulatus). Vision Res 2014; 102:19-25. [PMID: 25072853 DOI: 10.1016/j.visres.2014.07.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/08/2014] [Accepted: 07/10/2014] [Indexed: 11/21/2022]
Abstract
Birds are generally thought to have excellent vision with high spatial resolution. However, spatial contrast sensitivity of birds for stationary targets is low compared to other animals with similar acuity, such as mammals. For fast flying animals body stability and coordination are highly important, and visual motion cues are known to be relevant for flight control. We have tested five budgerigars (Melopsittacus undulatus) in behavioural discrimination experiments to determine whether or not stimulus motion improves contrast sensitivity. The birds were trained to distinguish between a homogenous grey field and sine-wave gratings of spatial frequencies between 0.48 and 6.5 cyc/deg, and Michelson contrasts between 0.7% and 99%. The gratings were either stationary or drifting with velocities between 0.9 and 13 deg/s. Budgerigars were able to discriminate patterns of lower contrast from grey when the gratings were drifting, and the improvement in sensitivity was strongest at lower spatial frequencies and higher drift velocities. Our findings indicate that motion cues can have positive effects on visual perception of birds. This is similar to earlier results on human vision. Contrast sensitivity, tested solely with stationary stimuli, underestimates the sensory capacity of budgerigars flying through their natural environments.
Collapse
|
9
|
Retinal ganglion cell topography and spatial resolution of two parrot species: budgerigar (Melopsittacus undulatus) and Bourke's parrot (Neopsephotus bourkii). J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2014; 200:371-84. [PMID: 24677162 DOI: 10.1007/s00359-014-0894-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 02/17/2014] [Accepted: 02/20/2014] [Indexed: 10/25/2022]
Abstract
Retinal ganglion cell (RGC) isodensity maps indicate important regions in an animal's visual field. These maps can also be combined with measures of focal length to estimate the theoretical visual acuity. Here we present the RGC isodensity maps and anatomical spatial resolving power in three budgerigars (Melopsittacus undulatus) and two Bourke's parrots (Neopsephotus bourkii). Because RGCs were stacked in several layers, we modified the Nissl staining procedure to assess the cell number in the whole-mounted and cross-sectioned tissue of the same retinal specimen. The retinal topography showed surprising variation; however, both parrot species had an area centralis without discernable fovea. Budgerigars also had a putative area nasalis never reported in birds before. The peak RGC density was 22,300-34,200 cells/mm(2) in budgerigars and 18,100-38,000 cells/mm(2) in Bourke's parrots. The maximum visual acuity based on RGCs and focal length was 6.9 cyc/deg in budgerigars and 9.2 cyc/deg in Bourke's parrots. These results are lower than earlier behavioural estimates. Our findings illustrate that retinal topography is not a very fixed trait and that theoretical visual acuity estimations based on RGC density can be lower than the behavioural performance of the bird.
Collapse
|