: 397 Words 20 Text Pages 5 Appendix Pages 5 Reference Pages 5 Table and Figure Caption Pages 17 Figures, 1 Table Running Title: Saccade Generator Model xSupported in part by the Defense Advanced Research Projects Agency and the O ce of Naval Research (ONR N00014-95-1-0409), the National Science Foundation (NSF IRI-9401659), and the O ce of Naval Research(ONR N00014-92-J-1309,ONR N00014-94-1-0597, and ONR N00014-95-1-0657). zSupported in part by the Defense Advanced Research Projects Agency and the O ce of Naval Research (ONR N00014-95-1-0409) and the O ce of Naval Research (ONR N0001492-J-1309 and ONR N00014-95-0657).