Measuring spatial visual loss in rats by retinotopic mapping of the superior colliculus using a novel multi-electrode array technique
The retinotopic map property of the superior colliculus (SC) is a reliable indicator of visual functional changes in rodents. Electrophysiological mapping of the SC using a single electrode has been employed for measuring visual function in rat and mouse disease models. Single electrode mapping is h...
Saved in:
Published in | Journal of neuroscience methods Vol. 405; p. 110095 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Netherlands
Elsevier B.V
01.05.2024
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | The retinotopic map property of the superior colliculus (SC) is a reliable indicator of visual functional changes in rodents. Electrophysiological mapping of the SC using a single electrode has been employed for measuring visual function in rat and mouse disease models. Single electrode mapping is highly laborious requiring long-term exposure to the SC surface and prolonged anesthetic conditions that can adversely affect the mapping data.
To avoid the above-mentioned issues, we fabricated a fifty-six (56) electrode multi-electrode array (MEA) for rapid and reliable visual functional mapping of the SC. Since SC is a dome-shaped structure, the array was made of electrodes with dissimilar tip lengths to enable simultaneous and uniform penetration of the SC.
SC mapping using the new MEA was conducted in retinal degenerate (RD) Royal College of Surgeons (RCS) rats and rats with focal retinal damage induced by green diode laser. For SC mapping, the MEA was advanced into the SC surface and the visual activities were recorded during full-filed light stimulation of the eye. Based on the morphological examination, the MEA electrodes covered most of the exposed SC area and penetrated the SC surface at a relatively uniform depth. MEA mapping in RCS rats (n=9) demonstrated progressive development of a scotoma in the SC that corresponded to the degree of photoreceptor loss. MEA mapping in the laser damaged rats demonstrated the presence of a scotoma in the SC area that corresponded to the location of retinal laser injury.
The use of MEA for SC mapping is advantageous over single electrode recording by enabling faster recordings and reducing anesthesia time. This study establishes the feasibility of the MEA technique for rapid and efficient SC mapping, particularly advantageous for evaluating therapeutic effects in retinal degenerate rat disease models.
•Rapid and reliable visual functional mapping of the rat SC.•Electrodes cover and penetrate the SC surface at a relatively uniform depth.•Mapping in rat models demonstrated scotoma corresponding to photoreceptor loss.•Efficient visual mapping for therapeutic effects in retinal disease models. |
---|---|
Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0165-0270 1872-678X 1872-678X |
DOI: | 10.1016/j.jneumeth.2024.110095 |