Journal of the International Neuropsychological Society

Research Articles

Noradrenergic Moderation of Working Memory Impairments in Adults with Autism Spectrum Disorder

Kimberly E. Bodnera1, David Q. Beversdorfa1a2, Sanjida S. Saklayena3 and Shawn E. Christa1 c1

a1 Department of Psychological Sciences, University of Missouri, Columbia, Missouri

a2 Department of Radiology and Neurology, University of Missouri, Columbia, Missouri

a3 College of Medicine, Ohio State University, Columbus, Ohio

Abstract

In addition to having difficulties with social communications, individuals with an autism spectrum disorder (ASD) often also experience impairment in higher-order, executive skills. The present study examined the effects of pharmacological modulation of the norepinephrine system on the severity of such impairments. A sample of 14 high-functioning adults with ASD and a demographically-matched comparison group of 13 typically developing individuals participated. An AX continuous performance test (AX-CPT) was used to evaluate working memory and inhibitory control. AX-CPT performance was assessed following administration of a single dose of propranolol (a beta adrenergic antagonist) and following placebo (sugar pill) administration. Individuals with ASD performed more poorly than non-ASD individuals in the working memory condition (BX trials). Importantly, administration of propranolol attenuated this impairment, with the ASD group performing significantly better in the propranolol condition than the placebo condition. Working memory performance of the non-ASD group was unaffected by propranolol/placebo administration. No group or medication effects were observed for the inhibition condition (AY trials). The present findings suggest that norepinephrine may play a role in some, but not necessarily all, cognitive impairments associated with ASD. Additional research is needed to fully understand whether this role is primarily causal or compensatory in nature. (JINS, 2012, 18, 556–564)

(Received July 22 2011)

(Revised January 16 2012)

(Accepted January 18 2012)

Correspondence:

c1 Correspondence and reprint requests to: Shawn E. Christ, Department of Psychological Sciences, 210 McAlester Hall, University of Missouri, Columbia, MO 65203. E-mail: christse@missouri.edu