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Event: 1643

Key Event Title

A descriptive phrase which defines a discrete biological change that can be measured. More help

Altered, Visual function

Short name
The KE short name should be a reasonable abbreviation of the KE title and is used in labelling this object throughout the AOP-Wiki. More help
Altered, Visual function
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Biological Context

Structured terms, selected from a drop-down menu, are used to identify the level of biological organization for each KE. More help
Level of Biological Organization

Organ term

The location/biological environment in which the event takes place.The biological context describes the location/biological environment in which the event takes place.  For molecular/cellular events this would include the cellular context (if known), organ context, and species/life stage/sex for which the event is relevant. For tissue/organ events cellular context is not applicable.  For individual/population events, the organ context is not applicable.  Further information on Event Components and Biological Context may be viewed on the attached pdf. More help
Organ term

Key Event Components

The KE, as defined by a set structured ontology terms consisting of a biological process, object, and action with each term originating from one of 14 biological ontologies (Ives, et al., 2017; Biological process describes dynamics of the underlying biological system (e.g., receptor signalling).Biological process describes dynamics of the underlying biological system (e.g., receptor signaling).  The biological object is the subject of the perturbation (e.g., a specific biological receptor that is activated or inhibited). Action represents the direction of perturbation of this system (generally increased or decreased; e.g., ‘decreased’ in the case of a receptor that is inhibited to indicate a decrease in the signaling by that receptor).  Note that when editing Event Components, clicking an existing Event Component from the Suggestions menu will autopopulate these fields, along with their source ID and description.  To clear any fields before submitting the event component, use the 'Clear process,' 'Clear object,' or 'Clear action' buttons.  If a desired term does not exist, a new term request may be made via Term Requests.  Event components may not be edited; to edit an event component, remove the existing event component and create a new one using the terms that you wish to add.  Further information on Event Components and Biological Context may be viewed on the attached pdf. More help
Process Object Action
vision trait eye functional change

Key Event Overview

AOPs Including This Key Event

All of the AOPs that are linked to this KE will automatically be listed in this subsection. This table can be particularly useful for derivation of AOP networks including the KE. Clicking on the name of the AOP will bring you to the individual page for that AOP. More help
AOP Name Role of event in AOP Point of Contact Author Status OECD Status
retinaldehyde dehydrogenase inhibition,population decline KeyEvent Young Jun Kim (send email) Under Development: Contributions and Comments Welcome Under Development
Inhibition of Fyna leading to increased mortality KeyEvent Vid Modic (send email) Open for citation & comment
TPOi retinal layer structure KeyEvent Lucia Vergauwen (send email) Open for citation & comment EAGMST Under Review
TPOi eye size KeyEvent Lucia Vergauwen (send email) Under development: Not open for comment. Do not cite Under Development
TPOi photoreceptor patterning KeyEvent Lucia Vergauwen (send email) Under development: Not open for comment. Do not cite Under Development

Taxonomic Applicability

Latin or common names of a species or broader taxonomic grouping (e.g., class, order, family) that help to define the biological applicability domain of the KE.In many cases, individual species identified in these structured fields will be those for which the strongest evidence used in constructing the AOP was available in relation to this KE. More help
Term Scientific Term Evidence Link
zebrafish Danio rerio High NCBI

Life Stages

An indication of the the relevant life stage(s) for this KE. More help
Life stage Evidence
Embryo High
Juvenile Moderate
Larvae High

Sex Applicability

An indication of the the relevant sex for this KE. More help
Term Evidence
Unspecific Moderate

Key Event Description

A description of the biological state being observed or measured, the biological compartment in which it is measured, and its general role in the biology should be provided. More help

The decrease in visual function can have different aspects, such as loss of chromatic vision, changes in eye movements, differences in sensitivity to light, but also changes in the retinal pigment epithelium (RPE) that may be related to a decrease in visual function (Strauss, 2005). The visual system is highly variable from one species to another, and this variability is a key factor influencing animal behaviour (Corral-López et al., 2017).

Decreases in these visual functions can have a strong impact on behaviour, leading to changes in individual response and abilities in the environment, including, for example, perception of food or avoidance of predators. Variation in the visual system can also influence learning tasks when visual stimuli are used (Corral-López et al., 2017).

Studies have detected visual impairments in fish at different temperatures (Babkiewicz et al., 2020) after treatment with the endocrine disruptor propylthiouracil (Baumann et al 2016 ), after chronic dietary selenomethionine exposure (Raine et al 2016), exposure to PCBs (Zhang et al, 2015) or deiodinase knockdown (Houbrechts et al 2016, Vancamp et al 2018).


How It Is Measured or Detected

A description of the type(s) of measurements that can be employed to evaluate the KE and the relative level of scientific confidence in those measurements.These can range from citation of specific validated test guidelines, citation of specific methods published in the peer reviewed literature, or outlines of a general protocol or approach (e.g., a protein may be measured by ELISA). Do not provide detailed protocols. More help

Measurements of visual function can be performed at the level of neuronal activity:

  • Electroretinography (Chrispell et al., 2015)
  • Analysis of neural activity in the optic tectum can be quantified as the ratio of phosphorylated extracellular signal–regulated kinase (ERK)      to total ERK in the optic tectum using immunofluorescent antibodies (Randlett et al., 2015, Dehnert et al., 2019).
  • Babkiewicz et al. (2020) used an advanced technique to display an artificial prey on a miniature OLED screen and use functional calcium imaging with light sheet microscopy to visualize a neural response in the optic tectum.

Other measurements are performed at the level of the eyes:

  • Opto Kinetic response, OKR (similar protocol for Rat/mice (Segura et al., 2018), fish (Zou et al., 2010) and humans (Kang and Wildsoet, 2016)). The OKR is a visually-mediated assay in which an individual will respond to alternating black and white stripes by exhibiting eye saccades, eye movements without coordinated body movements, in the same direction as rotating stripes. An eye saccade relies on the ability to rapidly move the eye from focusing on one external target to the next in a repeated manner (Magnuson et al., 2020). Optokinetic tracking has a robust performance and does not require training the animal, allowing for the quick assessment (and at earlier ages) of visual features such as visual acuity (VA) and contrast sensitivity (CS)11–14.      

Yet other studies use assessment of vision-related behaviours: 

  • Opto Motor Reponses, OMR. OMR tracks the ability of fish to swim in the direction of a perceived motion when presented with a whole-field stimulus (Neuhauss, 2003), (Gould et al., 2017)).
  • Light-dark transition or vision startle response: reaction to change in light intensity (light sensitivity) (Brastrom et al., 2019)
  • Black-white preference test (Baumann et al., 2016)
  • Diverse Mobility assay including Tracking, touch-evoked escape-response assays, Swirl assays, locomotion assay, swimming activity, phototactic swimming activity assay, induced locomotor response (LLR) (Baumann et al., 2016; Gao et al., 2015; Zhao et al., 2014, Dehnert et al., 2019).

Domain of Applicability

A description of the scientific basis for the indicated domains of applicability and the WoE calls (if provided).  More help

Taxonomic applicability: Visual function decrease can be evaluated in a wide range of species including mammals, amphibians, fish and humans. Evaluation of these visual function modifications change according to the species and its environment.

Life-stage applicability: Vision plays a crucial role in the early life stages of most species, as timing of eye development and establishment of functional vision is essential for perception of food or avoidance of predators for example (Carvalho et al., 2002). The first visual responses based on retinal functionality appear around 70 hpf in zebrafish (Schmitt and Dowling 1999). It is plausible to assume that alterations of the eye structure would result in altered visual function across all life stages, but such alterations are most likely to occur during the development of the normal eye structure, which occurs in the embryo-eleutheroembryo phase. Some studies have also shown a decrease in vision related to age (Brastrom et al., 2019; Martínez-Roda et al., 2016; Segura et al., 2018) including on visual acuity, visual fields, colour vision and dark adaptation, are well documented (Hennelly et al, 1998).

Sex applicability: Sex does not seem relevant for most of the visual function decreases observed in different studies. Differences according to the sex of the individuals have however been reported concerning the basic visual capacities (e.g. color perception, contrast sensitivity, visual acuity, motion perception,...) but also concerning the frequency of certain diseases influencing these diminished visual functions, notably in humans (Vanston and Strother, 2017).



List of the literature that was cited for this KE description. More help

Baumann, L., Ros, A., Rehberger, K., Neuhauss, S. C. F., & Segner, H. (2016). Thyroid disruption in zebrafish (Danio rerio) larvae: Different molecular response patterns lead to impaired eye development and visual functions. Aquatic Toxicology, 172, 44–55.

Babkiewicz, E., Bazała, M., Urban, P., Maszczyk, P., Markowska, M., & Maciej Gliwicz, Z. (2020). The effects of temperature on the proxies of visual detection of Danio rerio larvae: observations from the optic tectum. Biology Open, 9(7).

Brastrom, L.K., Scott, C.A., Dawson, D. V., Slusarski, D.C., 2019. A High-Throughput Assay for Congenital and Age-Related Eye Diseases in Zebrafish. Biomedicines 7, 28.

Carvalho, P.S.M., Noltie, D.B., Tillitt, D.E., 2002. Ontogenetic improvement of visual function in the medaka Oryzias latipes based on an optomotor testing system for larval and adult fish. Anim. Behav. 64, 1–10.

Chrispell JD, Rebrik TI, Weiss ER. 2015. Electroretinogram Analysis of the Visual Response in Zebrafish Larvae. Jove-Journal of Visualized Experiments(97).

Corral-López, A., Garate-Olaizola, M., Buechel, S.D., Kolm, N., Kotrschal, A., 2017. On the role of body size, brain size, and eye size in visual acuity. Behav. Ecol. Sociobiol. 71.

Dehnert GK, Karasov WH, Wolman MA. 2019. 2,4-Dichlorophenoxyacetic acid containing herbicide impairs essential visually guided behaviors of larval fish. Aquatic Toxicology 209:1-12.

Gao, D., Wu, M., Wang, C., Wang, Y., Zuo, Z., 2015. Chronic exposure to low benzo[a]pyrene level causes neurodegenerative disease-like syndromes in zebrafish (Danio rerio). Aquat. Toxicol.

Gould, C. J., Wiegand, J. L., & Connaughton, V. P. (2017). Acute developmental exposure to 4-hydroxyandrostenedione has a long-term effect on visually-guided behaviors. Neurotoxicology and Teratology, 64, 45–49.

Hennelly, M. L., Barbur, J. L., Edgar, D. F., & Woodward, E. G. (1998). The effect of age on the light scattering characteristics of the eye. Ophthalmic and Physiological Optics, 18(2), 197–203.

Houbrechts, A. M., Vergauwen, L., Bagci, E., Van houcke, J., Heijlen, M., Kulemeka, B., Hyde, D. R., Knapen, D., & Darras, V. M. (2016). Deiodinase knockdown affects zebrafish eye development at the level of gene expression, morphology and function. Molecular and Cellular Endocrinology, 424, 81–93.

Kang, P., & Wildsoet, C. F. (2016). Acute and short-term changes in visual function with multifocal soft contact lens wear in young adults. Contact Lens and Anterior Eye, 39(2), 133–140.

Magnuson, J., Bautista, N., Lucero, J., Lund, A., Xu, E. G., Schlenk, D., Burggren, W., & Roberts, A. P. (2020). Exposure to crude oil induces retinal apoptosis and impairs visual function in fish. Environmental Science & Technology.

Martínez-Roda, J. A., Vilaseca, M., Ondategui, J. C., Aguirre, M., & Pujol, J. (2016). Effects of aging on optical quality and visual function. Clinical and Experimental Optometry, 99(6), 518–525.

Neuhauss, S. C. F. (2003). Behavioral genetic approaches to visual system development and function in zebrafish. Journal of Neurobiology, 54(1), 148–160.

Raine, J. C., Lallemand, L., Pettem, C. M., & Janz, D. M. (2016). Effects of Chronic Dietary Selenomethionine Exposure on the Visual System of Adult and F1 Generation Zebrafish (Danio rerio). Bulletin of Environmental Contamination and Toxicology, 97(3), 331–336.

Randlett O, Wee CL, Naumann EA, Nnaemeka O, Schoppik D, Fitzgerald JE, Portugues R, Lacoste AMB, Riegler C, Engert F et al. . 2015. Whole-brain activity mapping onto a zebrafish brain atlas. Nature Methods 12(11):1039-1046.

Schmitt, E. A., & Dowling, J. E. (1994). Early‐eye morphogenesis in the zebrafish, Brachydanio rerio. Journal of Comparative Neurology, 344(4), 532–542.

Segura, F., Arines, J., Sánchez-Cano, A., Perdices, L., Orduna-Hospital, E., Fuentes-Broto, L., & Pinilla, I. (2018). Development of optokinetic tracking software for objective evaluation of visual function in rodents. Scientific Reports, 8(1), 1–11.

Strauss, O. (2005). The retinal pigment epithelium in visual function. Physiological Reviews, 85(3), 845–881.

Vancamp, P., Bourgeois, N. M. A., Houbrechts, A. M., & Darras, V. M. (2019). Knockdown of the thyroid hormone transporter MCT8 in chicken retinal precursor cells hampers early retinal development and results in a shift towards more UV/blue cones at the expense of green/red cones. Experimental Eye Research,178(September 2018), 135–147.

Zhang, X., Hong, Q., Yang, L., Zhang, M., Guo, X., Chi, X., & Tong, M. (2015). PCB1254 exposure contributes to the abnormalities of optomotor responses and influence of the photoreceptor cell development in zebrafish larvae. Ecotoxicology and Environmental Safety, 118, 133–138.

Zhao, J., Xu, T., & Yin, D. Q. (2014). Locomotor activity changes on zebrafish larvae with different 2,2’,4,4’-tetrabromodiphenyl ether (PBDE-47) embryonic exposure modes. Chemosphere, 94, 53–61.

Zou, S. Q., Yin, W., Zhang, M. J., Hu, C. R., Huang, Y. bin, & Hu, B. (2010). Using the optokinetic response to study visual function of zebrafish. Journal of Visualized Experiments, 36, 5–8.