Anne Fleur Kortekaas-Rijlaarsdam

CHAPTER 1 14 always optimal (e.g. type of feedback, appropriateness, timing) (Bond, Smith, Baker, & Hattie, 2000; Hattie & Timperley, 2007). Theoretical models of ADHD (Luman et al., 2005; Tripp & Wickens, 2009) suggest that children with ADHD show impairments in learning from feedback . These models are confirmed by data studies showing impaired accuracy on feedback learning tasks in children with ADHD (Groen et al., 2008; Luman, Van Meel, Oosterlaan, Sergeant, & Geurts, 2009), although not all studies confirm this (Luman, Goos, & Oosterlaan, 2015). However, studies on feedback learning in ADHD often use highly standardized laboratory tasks, which limit the generalizability of their results to classroom settings. Stimulant Treatment for ADHD The most commonly prescribed treatment for ADHD is stimulant medication. Evidence for the effectiveness of stimulant medication in reducing ADHD symptoms is robust with effect sizes (SMD) ranging from 0.5 to 1.83 (Antshel et al., 2011; Faraone, Biederman, Spencer, 2006; MTA-group, 1999b; Van der Oord, Prins, Oosterlaan, & Emmelkamp, 2008). Stimulants (methylphenidate and amphetamines) have been shown to be more effective than non-stimulants (atomoxetine, guanfacine and clonidine) in reducing ADHD symptoms, although responsiveness differs between individuals. Methylphenidate (MPH) is the most commonly prescribed stimulant for ADHD treatment (Faraone, Biederman, Spencer, 2006; Faraone et al., 2015). MPH is prescribed in immediate-release formulations and long-acting oral formulations, with the latter resulting in more constant blood plasma levels during the day and thus fewer rebound effects. Less regularly prescribed are transdermal MPH patches. Although the working mechanism of MPH is not fully clear, MPH has been shown to increase the availability of dopamine in the fronto-striatal areas of the brain by blocking dopamine and noradrenaline transporters (Pliszka, 2005; Seeman & Madras, 1998; Volkow et al., 2001; Volkow et al., 1998). As ADHD has been associated with low phasic dopamine and reduced neural activity in the fronto-striatal pathways (Tripp &Wickens, 2008), increases in availability of dopamine in these pathways most likely result in reduced ADHD symptoms (Dougherty et al., 1999; Tripp & Wickens, 2009; N D Volkow, Wang, Fowler, & Ding, 2005). Academic Improvements with Methylphenidate One of the primary reasons for parents and teachers to seek professional help and start medication treatment is malfunctioning in school (Wright et al., 2015). Besides robust improvements in behavior, MPH-related improvements in cognitive functions have