Attention Deficit/Hyperactivity Disorder (ADHD) is a common neurodevelopmental disorder that can have a significant impact on multiple facets of a child's life. Children with ADHD are generally considered to be more susceptible to distraction than other children; however, recent research has suggested that under certain circumstances, concurrent noise (e.g., music or white noise) may improve academic and cognitive performance in children with ADHD (Abikoff, Courtney, Szeibel, & Koplewicz, 1996; Pelham et al., 2011; Söderlund, Sikström, & Smart, 2007). These studies were not able to draw conclusions about which underlying cognitive processes may be improving with the addition of a concurrent auditory stimulus. This thesis contributes to current knowledge by investigating the impact of a concurrent auditory stimulus on attention in children with ADHD, as measured by performance on computer-based attention tasks. We are interested in whether a possible improvement in basic attentional processes could account for the improvements task performance observed in previous studies. The aim of the current thesis was to start to tease out which attentional processes, if any, may benefit from the presence of concurrent auditory stimulus such as white noise. Twenty-eight children with a diagnosis of ADHD-PI or ADHD-C were administered a battery of computer-based attention tasks under two noise conditions: a classroom noise only condition, and a classroom noise + white noise condition. The white noise stimulus comprised sounds of rain, administered using an iPhone application called Sleep Machine. The test battery consisted of four tasks assessing different types of attention - selective attention, sustained attention/vigilance, and aspects of executive attention (response inhibition and conflict resolution). White noise had no impact on children's performance on the task measuring response inhibition. For two of the attention tasks, the effects of white noise differed for medicated and non-medication children. Overall, a pattern emerged on the visual search and continuous performance tasks that suggested that white noise could improve attention in children with ADHD who are on stimulant medication (i.e., beneficial as an adjunct to medication). Further research is needed to clarify the impact of white noise on attentional processes for non-medicated children with ADHD. For the two executive attention tasks, a Go/no-go task and a Simon task, the white noise had no meaningful impact on task performance.