فرط الحركة و تشتت الإنتباه-1

يمكن تعريفه بأنه : اضطراب عصبي ، سلوكي ناتج عن خلل في بنية و وظائف الدماغ، يؤثر على السلوك و الأفكار و العواطف. وهو اضطراب يمكن التعامل معه و تخفيف حدة أعراضه بهدف مساعدة الطفل على التعلم و ضبط النفس مما يساهم برفع مستوى ثقته بنفسه و مواجهة قسوة الأطفال الآخرين . يتم التعرف على الطفل غالبا ما بين 5 إلى 9 سنوات و تستمر الأعراض عليه في فترة الطفولة و المراهقة . كذلك قد تستمر الأعراض أو بعضها في 30- 60% من الحالات إلى مرحلة الرشد 0

نسبة حدوث المشكلة :
تختلف نسبة حدوث فرط الحركة وقلة التركيز حسب الدراسات المختلفة ، ففي بعضها كانت النسبة من 3-5% بينما أظهرت دراسات أخرى نسباً أعلى ، حيث أظهرت دراسة أجريت على المدارس الابتدائية أن 17% من الأولاد و 8% من البنات تنطبق عليهم أعراض قلة التركيز وفرط الحركة .
وتنخفض هذه النسبة في فئة المراهقين لتصل إلى 11% الأولاد و 6% في البنات .
وبشكل عام فإن نسبة إصابة الأولاد إلى البنات هي1:4

أسبابADHD :

The Theories of the Causes of ADHD

The exact cause of ADHD remains undetermined, but the prevailing theories include genetic and hereditary factors, neurobiological conditions and pathologies, prenatal influences, nutritional factors and deficiencies and environmental/toxin influences.

Neurobiological Theories: Pathophysiological Views

While the exact cause of ADHD remains undetermined, frontal lobe lesions, anterior and medial to the pre-central motor cortex are considered the most likely neuroanatomic sources of ADHD. Cerebral blood flow studies have found central hypoperfusion in the frontal lobe and decreased blood flow to the caudate nucleus.

Positron emission tomography scans of parents of ADHD children who also have symptoms of ADHD have shown decreased glucose metabolism in left frontal and parietal regions. These findings suggest the prefrontal cortex, which governs auditory attention, is less active among those with ADHD. Neurostimulants such as Ritalin are thought to increase the activity of these brain regions. Electroencephalographic studies of ADHD patients reveal abnormal reaction potentials in response to novel stimulate after the subject has habituated to the test procedure.

Persons with ADHD have an unusually low rate of activity in brain areas responsible for motor control and attentiveness.

"Imaging Children with ADHD: MRI Technology Reveals Differences in Neuro-signaling". In this report, it was found that children with attention deficit-hyperactivity disorder (ADHD) may have significantly altered levels of important neurotransmitters in the frontal region of the brain, according to a study published in the December 2003 issue of the Journal of Neuropsychiatry and Clinical Neurosciences. "Our data show children with ADHD had a two-and-half-fold increased level of glutamate, an excitatory brain chemical that can be toxic to nerve cells," said lead author Helen Courvoisie, M.D., assistant professor, division of child and adolescent psychiatry, department of psychiatry and behavioral sciences at the Johns Hopkins Medical Institutions, Baltimore. "The data also suggest a decreased level of GABA, a neuro-inhibitor. This combination may explain the behavior of children with poor impulse contro

Genetic Theories of ADHD

Persons with ADHD have an unusually low rate of activity in parts of the brain areas responsible for motor control and attentiveness. However, the source of these neurological defects remain uncertain. Defects in the metabolism of dopamine, and, to a lesser degree, norepinephrine are postulated (Baren, 1995). Molecular Studies have shown a link between ADHD and the Dopamine transporter gene and the Dopamine DR D4 receptor gene.

Environmental & Other Possible Factors

Pregnancy and birth insults may affect the developing brain. Fetal exposure to alcohol has been linked to ADHD. Some argue that stress and poor nutrition during pregnancy can cause babies to have more allergic reactions that may cause developmental problems.

A variety of environmental factors, such as other pre- and perinatal abnormalities, central nervous system infections and reactions to sugar and food additives, are beginning to be evaluated with controlled studies.

Smoking , High Sugar, High Carbohydrate Diet during Pregnancy Related to Behavior Problems:

An Associated Press article published in April, 2000 indicated that smoking and eating a high carbohydrate, high sugar diet during pregnancy may be related to behavior problems in toddlers. Smoking lowers blood oxygen levels which is critical in fetal development, especially development of fetal brain cells. High carbohydrate, high sugar diets can also lower blood oxygen levels. Combined. these two factors may be related to ADHD behaviors in young children.

It's important for pregnant mothers to eliminate smoking and high carbohydrate and sugar foods from their diets to help maintain high blood oxygen levels to promote healthy fetal development and prevent possible behavior disorders in their children.

Toxicity from lead and thyroid dysfunction should be considered is assesssing ADHD as well.

Nutritional deficiencies (e.g., see: Deficiency in Omega-3 Fatty Acids Tied to ADHD in Boys) may also play a role.

Some of the most promising theories to date include exposure to various agents that can lead to brain injury (e.g., trauma, disease, fetal exposure to environmental toxins) and diminished brain activity.

ADD does occur in known biological syndromes, such as the fragile X and fetal alcohol syndrome. Psychosocial factors do not appear to play a primary etiologic role for the core symptoms, but certain types of parent/child interaction may be involved in the development of comorbid, oppositional and conduct disorder. Research also suggests that some predisposed children may become symptomatic after stressful or traumatic life events.

Environmental factors associated with ADHD include low birth weight, hypozia (too little oxygen) at birth, and exposure in utero to a number of toxins including alcohol, cocaine, and nicotine. Other studies have found correlations between certain toxic agents / nutrient deficiencies and learning disabilities.

المصدر: مركز الرحمة