Imageless thought refers to the type of thinking which occurs without sensory information such as visual content. This is evidenced by individuals’ ability to identify objects without having visual mental representations. This was experimented on by Oswald Kulpe, a German psychologist. Kulpe asked his research participants, who were in a darkened room, to visualize the colors which he was calling out. Interestingly, one of the participants recognized the color but did not have a visualization even if he did not have any mental deficit. Kulpe then concluded that there are certain concepts which may not be associated with a mental image.