aProgram in Neuroscience, Florida State University, Tallahassee, FL 32306, USA
bDepartment of Psychological and Brain Sciences and the Gill Center, Indiana University, Bloomington IN 47405, USA
*Corresponding author. Address: Program in Neuroscience/Psychology, Florida State University, 1107W. Call St., Tallahassee, FL 32306–4301, USA. Tel.: +1 850 644 5741; fax: +1 850 644 9874.
E-mail address:[email protected]
1Present address: Merck Research Laboratories, Boston, MA 02115, USA.
E-mail address:[email protected]
2Present address: Vanderbilt University Medical Center, Nashville, TN 37232, USA.
E-mail address:[email protected]
3Present address: Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
E-mail address:[email protected]
Submitted June 19, 2010; revised August 17, 2010; accepted August 20, 2010.