Title: Dopamine D2 receptors modulate the cholinergic pause and inhibitory learning Running Title: D2Rs modulate cholinergic pause and behavior

1 Department of Biological Sciences, Fordham University, 441 E. Fordham Road, Bronx, NY 10458 2 Department of Psychiatry, Columbia University, 1051 Riverside Drive, New York, NY 10032 3 Department of Neuroscience, Columbia University, 1051 Riverside Drive, New York, NY 10032 4 State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, PKUIDG/McGovern Institute for Brain Research, Beijing 100871, China 5 Department of Molecular Pharmacology and Therapeutics, Columbia University, 1051 Riverside Drive, New York, NY 10032 6 Division of Molecular Therapeutics, New York State Psychiatric Institute, 1051 Riverside Drive, New York, NY 10032 7 Department of Psychology, Barnard College 3009 Broadway, New York, NY 10027