ADD is believed to be caused by the brain's inability to focus on important information. ADD also affects the brain's ability to filter out unimportant information. Some researchers believe that ADD is caused by deficits in the brain's executive functioning. Executive functioning is believed to be centered in the frontal lobe.
It is believed that ADD medications, typically stimulants, boost frontal lobe functioning. In people with ADD, this enables the brain to work more effectively to regulate attention.
People with ADD may not appear to have a problem. In fact, school children with ADD may be overlooked because of their invisible disability. Students with ADD may have learning problems because of their inability to attend to important information. Some may see ADD students as lazy daydreamers. ADD may also cause students to appear uncooperative and have low motivation. As a result, ADD may be viewed as a behavior problem rather than the learning problem it really is.
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