visual stimulus visible light stimulus 2013-03-13T12:03:39Z Exposure to visible light in a manner, such as for a length of time or at a level, which would not be considered natural, usual or environmental and which is designed to elicit or evoke an action or response in a cell, an excitable tissue, or an organism. XCO:0000283 experimental_condition_ontology jsmith light therapy phototherapy controlled visible light exposure