It’s thought that ADD is caused by an underactive “noise suppression” function of the brain, causing sufferers to be subjected to less filtered sensory input that makes it harder for them to focus on the tasks at hand. It’s further supposed that stimulants like Ritalin and amphetamines “wake up” the filtering apparatus, thus paradoxically allowing focus (and for the hyperactive, reducing the need to constantly move.)

This study is another bit of evidence showing that these plausible theories have some substance.

More on education and child development :

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Real-Life “Hunger Games”: Soft Oppression Destroys the Poor
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Real Self-Esteem: Trophies for Everyone?
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