Both a Nicotinic Single Nucleotide Polymorphism (SNP) and a Noradrenergic SNP Modulate Working Memory Performance when Attention is Manipulated. - Pamela M. Greenwood; Ramya Sundararajan; Ming-Kuan Lin; Reshma Kumar; Karl J. Fryxell; Raja Parasuraman (J. Cogn. Neurosci., 2009)