New Findings in Brain Imaging of ADHD in Childhood and Adolescents

Computed Tomography Scan (CT Scan) was the first neurological imaging equipment used on a large scale which allowed the assessment of structural lesions of the brain such as tumors and stroke. Magnetic Resonance Imaging (MRI) enabled the more precise investigation of smaller lesions of the brain as well as abnormalities of the white matter. In addition to neurostructural imaging by means of CT Scan and MRI which occurred in neurofunctional imaging، it enabled clinical scientists to gain a unique knowledge of the human brain by using Positron Emission Tomography (PET) and Single-Photon Emission Computed Tomography (SPECT). The literature discussed specifically with regard to ADHD is the result of the latest studies and investigations achieved via modern neurological imaging techniques. By using the library method، the latest papers published in the PubMed website، American Journal of Psychiatry (AJP)، British Journal of Psychiatry (BJP)، and Neuroscience website in this area during a specific period of time from 2007 to 2014 were investigated. The findings of the investigation of damaged areas by means of imaging showed that none of the studies discussed a specific region or part of the brain as the main site of likely damages responsible for ADHD، neither did they make any definite emphasis or have consensus. Each study mentioned a different area or region of the brain as being responsible for such disorder. Despite the willingness and aim of all researchers involved in the areas of psychiatry and other neurological sciences، none of the functions or disorders of the brain has been attributed to a specific part or structure of the brain so far، because the brain functions as a very complex system consisting of billions of intertwined neurons and synaptic structures thus making it impossible to segregate and determine the duties of each part of the brain without investigating the other parts of the brain and their relationships with one another. That is why the general term of ‘minimal brain damage’ was used to explain the cerebral pathology of this disorder in the past، and it has not lost its application despite all the advancements made in this area.