aDivision of Neuroscience, Department of Oral and Maxillofacial Surgery, University of California at San Francisco, San Francisco, CA, United States

bDivision of Neuroscience, Departments of Preventative & Restorative Dental Sciences and Oral & Maxillofacial Surgery, University of California at San Francisco, San Francisco, CA, United States

cDivision of Neuroscience, Departments of Medicine and Oral & Maxillofacial Surgery, UCSF Pain and Addiction Research Center, University of California at San Francisco, San Francisco, CA, United States

*Corresponding author. Address: University of California, San Francisco, 513 Parnassus Ave, San Francisco, CA 94143-0440, United States. Tel.: 476-5108; fax: 476-6305. E-mail address: [email protected] (J. D. Levine).

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