Table 2.

Studies examining the contribution of prefrontal catecholamines to the behavioral and neural correlates of working memory in human subjects.

Studies are grouped based on methodology: drug administration, PET, effects of genetic polymorphisms, and medication withdrawal in Parkinson's patients. Abbreviations and drug actions: DA, dopamine; bromocriptine, a D2 agonist; pergolide, an agonist for both D1 and D2 receptors; haloperidol, non-specific DA agonist; methylphenidate, amphetamine, and dextroamphetamine: stimulants producing an increase in PFC DA and NE release; sulpiride, D2 antagonist; guanfacine, alpha-2A agonist; clonidine, alpha-2 agonist; SCH23390, D1 receptor antagonist; DAT1, dopamine transporter gene; COMT, catechol-O-methyltransferase gene; 5-HTT, serotonin transporter gene; DARPP-32, dopamine- and cAMP-regulated neuronal phosphoprotein gene; DRD2, dopamine receptor D2 gene; WM, working memory; PET, positron emission tomography; dlPFC, dorsolateral prefrontal cortex.