Abstract
Although ADHD is known as a childhood disorder, it is prevalent among adults as well. Several studies have been conducted on the etiology of this disorder and its neurobiological and neuroanatomical manifestations in children, but the knowledge of adult ADHD is not enough. The present research was aimed at studying the structural brain abnormalities in adult ADHD cases. Fifteen adult patients diagnosed with ADHD, developed during their childhood, were selected for this study. In addition to clinical interview and Magnetic Resonance Imaging (MRI), all the participants were asked to fill the (ASRS-VI.I). The results indicated that about 40 % of adults with ADHD suffer from structural brain abnormalities. The results of MRI showed that 100% of the individuals with inattentive and combined types of ADHD were structurally damaged but MRI results did not reveal any structural brain abnormalities in hyperactive participants. The results of the present study are somewhat consistent with the results of previous studies. In general, any brain injury in the region related to cognitive processes (such as attention, memorization, and prevention) and brain circuits related to motor functions and motivation can contribute a role to the induction of ADHD symptoms. It is recommended to conduct more researches in the future with larger samples using other methods that are capable of assessing brain performance and the level and mechanism of the functions of neurotransmitters and neuronal modulators.