The search image as link between sensation, perception and action

In this paper, it is argued that Jakob von Uexküll's "search image" notion, the original version of this notion within ethology, is still of use. A search image, in Uexküll's sense, is an imagined object that an organism has in mind when it searches for something. Uexküll's conception of the search image is useful both for understanding the theoretical context of contemporary notions of search images, and with an eye to envisioning possible future developments of the idea. Uexküll's classical notion differs from contemporary versions in that it has a wider application, and is therefore of greater relevance to theoretical biology and cognitive science. It constituted an integral part of his ground-breaking Umwelt theory, stressing the fundamental plasticity of the Umwelt, the subjective lifeworld of an animal or human subject. In a contemporary development of Umwelt theory, expressed by the tripartite Umwelt model, the search image notion represents a key connection between the directly experienced core Umwelt and the mediated Umwelt. However, the key function that schemata have in cognitive processes is also the starting point for mistakes in perception. This article details both the constructive function search images have in animal and human perception, and the mismatches in perception they can lead to. It also explains how the existence of search images can help explain puzzles concerning subjective and neural time in contemporary cognitive science.