Dexamphetamine boosts naming treatment effects in chronic aphasia EMMA WHITING, 1 HELEN J. CHENERY, 1 JONATHAN CHALK, 2 and DAVID A. COPLAND 1 1 Division of Speech Pathology, School of Health and Rehabilitation Sciences, The University of Queensland, Australia 2 Department of Medicine, School of Medicine and Centre for Magnetic Resonance, The University of Queensland, Australia (Received December 3, 2006; Final Revision May 20, 2007; Accepted May 21, 2007) Abstract To date, minimal research has investigated the effect of combining dexamphetamine with standard naming therapy after stroke. The present study used a double-blind, placebo-controlled, multiple baseline, crossover design with two individuals in the chronic stage of stroke recovery. Each individual attended two 4-week blocks of naming therapy (two to three treatment sessions per week). Dexamphetamine (10 mg) was administered at the start of each session during one therapy block, while a placebo was administered during the other therapy block. Therapy progress on treated and untreated items was assessed by a confrontation naming task during and after each therapy block. Both individuals showed greater progress in therapy and maintenance of therapy gains when behavioral treatment was combined with dexamphetamine rather than placebo, although this gain was only statistically significant in one individual. There was no significant improvement on a control task (nonword reading) in either individual. The results provide preliminary evidence that dexamphetamine paired with combined semantic and phonological therapy may be beneficial for the treatment of naming disorders in chronic aphasia. ( JINS, 2007, 13, 972–979.) Keywords: Pharmacotherapy, Amphetamine, Stroke, Anomia, Naming therapy, Aphasia INTRODUCTION Previous research has found that dexamphetamine can improve general speech 0 language recovery in the acute recovery stage after stroke in a nonblinded single case study (Walker-Batson et al., 1990) and in a nonblinded case series study with six participants (Walker-Batson et al., 1992). However, the significance of these results is difficult to gauge, given the open label (nonblinded) nature of the stud- ies. Nonetheless, a more recent double-blind, placebo- controlled study by Walker-Batson and colleagues (2001) also found that dexamphetamine improved general acute- stage speech 0 language recovery compared with a placebo. To date, few studies have specifically investigated the effects of dexamphetamine on word retrieval therapy. McNeil et al. (1997) found that dexamphetamine did not improve naming beyond the level achieved with behavioral therapy (therapy involved synonym and antonym generation) in an individual with chronic aphasia poststroke. It is important to note that the participant was 3 years poststroke. The time frame during which dexamphetamine may assist functional recovery poststroke remains unknown (de Boissezon et al., 2007; Knecht et al., 2001; Nadeau & Wu, 2006; Shisler et al., 2000; Walker-Batson et al., 2004), however, it has been argued that it may be more effective in the acute recov- ery stage (de Boissezon et al., 2007; Walker-Batson et al., 2004), thus the participant may have been at a recovery stage where dexamphetamine was of little benefit. The find- ing by McNeil et al. (1997) that naming improved only when the participant received behavioral therapy, but not the drug alone, is consistent with data suggesting that dex- amphetamine is most effective when administered in con- junction with behavioral therapy designed specifically to target the neurological impairment (Crisostomo et al., 1988; Long & Young, 2003; Martinsson & Eksborg, 2004; Nadeau & Wu, 2006; Nudo et al., 2001; Walker-Batson et al., 1995). Of interest, research with healthy adults has also found that dexamphetamine paired with task-specific training can sig- nificantly facilitate normal behavioral learning mecha- nisms (e.g., Breitenstein et al., 2004; Nadeau & Wu, 2006; Soetens et al., 1995; Whiting et al., 2007a,b). Correspondence and reprint requests to: David Copland, Division of Speech Pathology, School of Health and Rehabilitation Sciences, The University of Queensland, St Lucia, Queensland, Australia 4072. E-mail: d.copland@uq.edu.au Journal of the International Neuropsychological Society (2007), 13, 972–979. Copyright © 2007 INS. Published by Cambridge University Press. Printed in the USA. DOI: 10.10170S1355617707071317 972