The development of brain is quite different in preschool children with ADHD/ADD. The preschool children with symptoms of attention deficit hyperactive disorder exhibited less developed portion of brain that is responsible for motor control than a normal child of same age. This study was concluded by clinical Neuropsychologist of Kennedy Krieger Institute. The knowledge of brain differences may make early intervention of ADHD possible.

Via: http://www.sciencedaily.com/releases/2010/02/100203084302.htm 

Radiological Society of North America presented its study on 28th November, 2011 in Science Daily. Their study helped in knowing the abnormalities of brain in attention deficit hyperactive disorder. They studied and identified these peculiarities of ADHD child through fMRI (Functional Magnetic Resonance Imaging).

Via: http://www.sciencedaily.com/releases/2011/11/111128120138.htm

ADHD Center of Mount Sinai, funded by NIH (National Institute of Health) based their study on MRI ( Magnetic Resonance Imaging). They studied the pattern of brain activation of ADHD children with the help of functional MRI. The researchers were then able to prove that although the pattern of brain is same in children with ADHD but the development of brain is slow in such children.

Via: http://en.wikipedia.org/wiki/ADHD_predominantly_inattentive#Research

Multimodal treatment study for ADHD (MTA) funded by NIMH made extensive research on children suffering from ADHD and the effect of medicines on such children. This study is based on the research by MTA that concluded the harmful effects of medicines on such children and adults who are suffering from attention deficit hyperactivity disorder. It can affect the various organs especially heart of the body although B.P shows no effect. They studied this for 14 months and gave their conclusion based on that. Alternate to medicine such as exercising, planning a routine, etc were also helpful in treating ADHD.

Via: http://www.nimh.nih.gov/health/topics/attention-deficit-hyperactivity-disorder-adhd/index.shtml 

According to the study by AHRQ, the EHR (electronic health record) of children with attention deficit disorder can accentuate the quality of their care. Such children need better support and guidance of pediatrician and their parents in order to gain success in academics and relationships. About 412 children diagnosed with ADD/AHHD were selected for this study from different centers of primary care in Massachusetts. 79 pediatricians took the responsibility of these children. They studied the symptoms and effects of treatment on these children after every 3-6 months. Most of the children of intervention group (71%) had visited their pediatrician showed better results. The researchers believed that proper documentation of ADHD symptoms and study of adverse effects along with effectiveness of treatment were responsible for the success of this study.

Via: http://www.ahrq.gov/research/apr11/0411RA24.htm