109 0-8493-1243-4/02/$0.00+$1.50 © 2003 by CRC Press LLC 5 Modular Complexity of Area V2 in the Macaque Monkey Anna W. Roe CONTENTS 5.1 Introduction .................................................................................................. 109 5.1.1 Optical Imaging of V2 ..................................................................... 110 5.2 Redefining Relationships with V1 ............................................................... 112 5.2.1 Revision of Anatomical Connectivity.............................................. 112 5.2.2 Functional V1–V2 Interactions Revealed by Cross-Correlation ..... 116 5.2.3 Blobs-to-Thin Stripes: Three Classes of Color Interactions ........... 117 5.2.4 Interblobs-to-Thick/Pale Stripes: Two Classes of Oriented Interactions ....................................................................................... 117 5.3 Modular Complexity within V2 Stripes ...................................................... 118 5.3.1 Thin Stripes: Modular Representation of Surface Color and Brightness ......................................................................................... 119 5.3.2 Thick/Pale Stripes: Modular Representation of Complex Contours ........................................................................................... 121 5.3.2.1 Diversity of Higher-Order Contour Cells in V2 .............. 121 5.3.2.2 Localization: Evidence for Complex Orientation Domains in V2 .................................................................. 123 5.3.2.3 Feedback: Changing Balance between Two Orientation Networks ........................................................................... 123 5.3.3 Thick Stripes: Modular Representation of Relative Disparity ........ 126 5.4 Border and Surface Capture: Foundation for Figure Integration................ 127 5.5 Summary and Proposal ................................................................................ 130 Acknowledgments.................................................................................................. 132 References .............................................................................................................. 132 5.1 INTRODUCTION Area V2 has traditionally been thought of as the second stage of visual cortical processing in the primate. In addition to receiving ascending feedforward inputs 1243_book.fm Page 109 Thursday, May 22, 2003 10:45 AM