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Attentional modulation of neural processing of shape, color, and velocity in humans. Science 248, 1556–1559 (1990). 69. Huk, A. C., Ress, D. & Heeger, D. J. Neuronal basis of the motion aftereffect reconsidered. Neuron 32, 161–172 (2001). 70. Blake, R. & Logothetis, N. K. Visual competition. Nature Rev. Neurosci. 3, 13–21 (2002). 71. Douglas, R. J., Martin, K. A. C. & Whitteridge, D. A canonical microcircuit for neocortex. Neural Comput. 1, 480–488 (1989). 72. Bartels, A., Logothetis, N. K. & Moutoussis, K. FMRI and its interpretations: An illustration on directional sensitivity in area V5/MT. Trends Neurosci. (in the press). Supplementary Information is linked to the online version of the paper at www.nature.com/nature. Acknowledgements I thank my co-workers A. Bartels, J. Goense, M. Munk and A.-C. Zappe for discussions; my colleagues P. Hoffmann, C. Koch, K. Martin, A. Schu¨z, C. Kayser and R. Turner for their insightful comments and suggestions on the latest version of the article; J. Goense, B. Weber and A. L. Keller for providing graphics; and D. Blaurock for language corrections. The work is supported by the Max Planck Society. Author Information Reprints and permissions information is available at www.nature.com/reprints. Correspondence should be addressed to N.K.L. (nikos.logothetis@tuebingen.mpg.de). REVIEWS NATUREjVol 453j12 June 2008 878 ©2008 Macmillan Publishers Limited. All rights reserved