In accomplishing some tasks, biological visual systems can outperform even the most sophisticated image processing systems. The goal of this research is to build optoelectronic circuits which perform some important image sensing and processing tasks in a somewhat similar manner to the biological visual systems. The circuits are then not only useful in performing these tasks better than conventional methods, but also provide a tool of analysis, a level of abstraction, for the original biological systems. This goal is methodically pursued by proposing elements of a visual system that are based on a basic model of ionic conduction in nerve membranes. Processing capabilities of each of the proposed elements is demonstrated. Next, more sophisticated tasks are proposed which can be performed by combining these basic elements together. It is argued that this intelligent control of acquisition of visual data is essential for real time operation in a complex dynamic world.//