en Clinical Neuroscience Clinical Neuroscience Original Original <p style="direction: ltr; margin-right: 18.95pt; text-align: justify;"><strong>Introduction:</strong> Contrary to Diagnostic and Statistical Manual of Mental Disorders (DSM-5), fifth edition, some studies indicate that ADHD-inattentive presentation (ADHD-I) is a distinct diagnostic disorder and not an ADHD presentation.&nbsp;<br> <strong>Methods:</strong> In this study, 12 ADHD-combined presentation (ADHD-C), 10 ADHD-I, and 13 controls were enrolled and their resting state EEG recorded. Following this, a graph theoretical analysis was performed and functional integration and segregation of brain network was calculated.&nbsp;<br> <strong>Results:</strong> The results show that clustering coefficient of theta band was significantly different among three groups and significant differences were observed in theta global efficiency between controls and ADHD-C. Regarding the alpha band, a lower clustering coefficient was observed in control subjects. In the beta band, clustering coefficient was significantly different between the control and children with ADHD-C and also between ADHD-I and ADHD-C. The clustering coefficient, in the subjects with ADHD-C, demonstrated a rapid decline and was significantly lower than the subjects with ADHD-I and control.&nbsp;<br> <strong>Conclusion:</strong> Decreased clustering, in high thresholds, may be associated with hyperactivity while increased segregation in low thresholds with inattentiveness. A different functional network occurs in the ADHD-C brain that is consistent with several studies that have reported ADHD-I as a distinct disorder.&nbsp;</p> ADHD presentations, Graph theory, Brain segregation, Brain integration, EEG 267 278 http://bcn.iums.ac.ir/browse.php?a_code=A-10-914-1&slc_lang=en&sid=1 Amir Hossein Ghaderi a_ghaderi@tabrizu.ac.ir 13700319475328460010872 13700319475328460010872 Yes Cognitive Neuroscience Laboratory, Department of Psychology, University of Tabriz, Tabriz, Iran. Mohammad Ali Nazari nazaripsycho@yahoo.com 13700319475328460010873 13700319475328460010873 No Cognitive Neuroscience Laboratory, Department of Psychology, University of Tabriz, Tabriz, Iran. Hassan Shahrokhi shaahrokhi.hasan@yahoo.com 13700319475328460010874 13700319475328460010874 No Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences, Tabriz, Iran. Amir Hossein Darooneh darooneh@znu.ac.ir 13700319475328460010875 13700319475328460010875 No Department of Physics, Faculty of Sciences, University of Zanjan, Zanjan, Iran.