Attention Deficit Hyperactivity Disorder (ADHD) is a state of the brain that leads to excessive activity ,inattention and impulsivity culminating in impaired social behavior especially in children. It's a chronic disorder which if not treated its symptoms can persist to adulthood. Its prevalence in boys is almost four times higher than in girls (Wender , 2000) .
The symptoms of this condition can be classified into three: predominantly inattentive type ,predominantly hyperactive-impulsive type or combined type. The symptoms for predominantly inattentive type include the tendency to get easily distracted, the tendency to easily miss details, the tendency to forget things easily and the tendency to lose concentration in an activity (Wender , 2000). A person with this disorder finds it difficult to focus on one thing, gets bored with an activity only after a few minutes of doing it unless the activity is interesting and doesn't pay attention when being spoken to.
Other symptoms of predominant inattention include daydreaming, confusion and the tendency to move slowly. The impulsive behavior is manifested as: impatience, act emotionally and without restraint, blurt out comments recklessly as well as acting without regard for the resulting consequences (Wender , 2000). Predominantly hyperactive-impulsive type symptoms include: restlessness, unrestrained fidgeting, noisiness, tendency to play with nearly everything in sight. Symptoms may persist to adulthood for up to half the victims. Note however that diagnosing ADHD in adults is a clinical procedure. ADHD therefore in adults would be different from say adults due to adaptive processes and avoidance habits learned during socialization(Wender , 2000) . Diagnosis of ADHD becomes tricky since there are many other cormobidities whose symptoms overlap those of ADHD. Such cormobid disorders include but not limited to: conduct disorder, antisocial personality disorder, anxiety disorder, bipolar disorder oppositional defiant disorder (ODD), mood disorders, personality borderline disorder , among others (Wender , 2000).
Causes of ADHD are not quite clear but environment, genetic make-up and the social setting where an individual grows up are known to be possible causes.
The environmental causes mainly centre around diet. Food additives like artificial colors ( e.g. Ponceau.4R, Sunset yellow.FCF (E110), quinolline yellow(E104), Tartrazine(E102) and carmoisine (E122), as well as food preservatives like sodium benzoate (Wender , 2000) . A study conducted by researchers at Southampton University in the United Kingdom and published in 'The Lancet' on November 3, 2007 found an association between intake of many artificial food colors as well as sodium benzoate-a preservative, with hyperactivity. Other than food additives, alcohol and tobacco especially exposure during pregnancy, where the nicotine in tobacco causes hypoxia (oxygen insufficiency) to the foetus, complications during delivery may also play a role. Sugar has also been shown to play a role although researchers seem to dispute the role played by sugar. In a research where mothers had their children.. given aspartame while others received sugar, those receiving sugar were reported as more hyperactive than those receiving aspartame(Neven , 2002) .
Organophosphates especially those used in insecticides such as chlorpyrifos which is used on some vegetables and fruits have been linked to delays in learning rates, reduced physical coordination and behavioral problems in children especially ADHD. A 2010 study by WHO found that pesticide exposure increases ADHD risk in children. Researchers analyzed organophosphate residues in the urine of over 1,100 children of ages 8-15 years and found that those with the highest levels of dialkyl phosphates which are the breakdown which are the breakdown products of organophosphate pesticides had the highest incidences of ADHD. On average, the study indicated that every 10-fold increase in the pesticide residues results in 35% probability of developing ADHD (Neven , 2002) .Want an expert to write a paper for you Talk to an operator now
Other than environment, genes are believed to exert some influence. ADHD has been shown to run in families. Researchers believe that a large majority of ADHD cases arise from a combination of various genes many of which affect dopamine transporters. It has often been shown that ADHD does not follow the traditional model of a disease. ADHD should therefore be seen as a complex interaction of among genetic and environmental factors (Neven , 2002) .
The other major factor thought to cause ADHD is the social setting where an individual grows up. For instance children who have suffered violence and emotional abuse have had behavior typical of ADHD; Complex post traumatic stress disorder can result in attention problems which resemble ADHD (Neven , 2002) . A report released this year by CNN show that there is an increased risk for internationally adopted children to develop mental disorders such as ADHD and ODD(Oppositional Defiant Disorder) The risk may be related to the time the children spent in orphanage and more so if the children were neglected (Neven , 2002) .
The average onset of the disorder is between ages 3 to 4 years which coincides with school entry age. The disorder first presents with a pattern of hyperactive-impulsive behavior and in some cases oppositional and aggressive conduct. The combined type starts between the ages of 5 to 8, while the inattentive type starts between ages 8-12 years. 50-80 percent of clinic-referred children continue with the disorder into adolescence. . The Inattention and hyper-impulsive behavior however declines with adolescence. The prevalence of the disorder is relatively low in adulthood (Neven , 2002) .
The treatment of this disorder combines behavior modification, counseling , changes in lifestyle and medication. Behavioral modification involves psycho-educational input ,cognitive behavioral therapy ,family therapy , interpersonal psychotherapy ,training and parent management training and school related interventions. Parent training and education have been found to have short-term benefits and are therefore unreliable (Neven , 2002) .
Medication is the most cost -effective method of managing ADHD. This method takes many forms with stimulant medication being a case in point. Stimulant medication is actually the most preferred and prescribed. most stimulant medications include: methylphenidate , dextroamphetamine , dextromethamphetamine , and lisdexamfetamine . These stimulants increase the extracellular concentrations of neurotransmitters like dopamine and norepinephrine and this results to a surge in neurotransmission. The dark side of using stimulant medication is 'drug tolerance' to therapeutic doses. Note that continued exposure to these stimulants results in low production of the neurotransmitter by the brain as it adapts to the surge, or the brain lowers production of the corresponding receptors (Neven , 2002) . Low dopamine levels can raise the threshold at which someone can maintain focus on a task which is otherwise boring. The person most likely increases the dosage as they attempt to bring the neurotransmitter level back to normal. Drug tolerance can affect the long term health of the individual affected (Neven , 2002).
Antipsychotic medication involves the use of antipsychotic drugs which block excessive neurotransmission, in some cases blocking dopamine function. The advantage of these drugs is that they are less likely to result in movement disorders, dysphoria and increased drug cravings. The adverse effect of this medication is that it can easily result in weight gain, diabetes, fatigue, sexual dysfunction among others (Neven , 2002) .
Other non-stimulant medications include Atomoxetine (strattera) and Guanfacine. Dietary supplements and specialized diets may reduce the symptoms associated with the disorder. Omega-3 fatty acid rich supplementation (seal fish or krill oil) may reduce symptoms for a subgroup of children and adolescents with the disorder characterized by inattention and neurodevelopmental problems (Delfos , 2004) .
Athletics or any form of aerobic activity if such is not accompanied with negative behaviors or stigma may increase peer acceptance and mitigate complication of the disorder. Art , video games, cutting down on time spent on television may reduce severity.
Positive change in diet such as low sugar intake, low additives, no caffeine and outdoor adventures in parks can positively reduce the severity of ADHD (Delfos , 2004) .
The areas of the brain affected by the disorder are not entirely clear. However, there is a prominent delay in development of frontal cortex and temporal lobe of the brain in most children. These two structures are responsible for the ability to control and focus thinking thus the thinking capability becomes impaired. The motor cortex in the ADHD patients is found to mature faster than normal which suggests that slower development of motor cortex is essential for behavioral control in ADHD victims (Delfos , 2004) . There is a marked reduction in brain volume for ADHD victims but mainly the prefrontal cortex. Studies suggest that a frontal lobe dysfunction can significantly be associated with the hyperactivity, impulsivity and inattention observed in ADHD victims. Cerebellum dysfunction has also been implicated (Delfos , 2004) .
Blood circulation in these patients is reduced which results in a low neural activity. There could be significant thinness of the cortex of the right side of the brain where the '7-repeat' variant of the D4 receptor gene which accounts for 30% of the genetic risk of ADHD is involved though the region normalizes in thickness during teenage in these children and this coincides with clinical improvement (Delfos , 2004) .