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DanaJ
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For years, people who have recognized that many children are inherently active have assumed that those who were particularly hyper would simply outgrow such a phase. Today some skeptics still believe that those diagnosed with ADD are simply people who lack willpower and discipline. Yet, given the progress that has been made in understanding the ADD mind, it is increasingly clear that ADD is a very real chemical impairment of the brain that persists in adulthood for 30-50% of those diagnosed as children.
For many years, what is now called ADD was perceived as childhood behavior characterized by impulsivity and an inability to sit still. In the 1970's, researchers first recognized that hyperactive children also had tremendous difficulty maintaining the attention required to complete tasks or listen to their teachers. This realization that inattention rather than hyperactivity was the principal problem led to the first major paradigm shift in understanding ADD syndrome.
Recently, there has been another major change in our understanding of ADD. Researchers have now recognized that ADD symptoms overlap with impairments in executive functions, the brain circuits that prioritize, integrate, and regulate other cognitive functions. Impairment in these functions stems from the brain's inability to inhibit impulses. The brain of a person with ADD may have difficulty forestalling the impulse to speak out of turn, the inclination to intentionally irritate a sibling (despite knowledge that such action will lead to punishment), the distraction of paperclips on a desk, or the desire to play outside before math homework has been completed.
Persons with ADD who use stimulant medications often experience improvements in executive brain functions and impulse inhibition. There is now considerable evidence that executive functions depend on neurotransmitter chemicals such as dopamine. Stimulant medications like Ritalin affect these chemicals at neural synapse sites that control crucially important executive functions. Stimulants are not without risks and side effects, and stimulants do not cure ADD. But they do alleviate symptoms while the dose of medication is active.
Much remains to be learned about how the brain's complicated neural networks operate to sustain attention. Yet it seems clear that impairment of executive functions, those brain processes that organize and activate what we generally think of as attention, are the result of the disruption of neurotransmitter pathways in the brain. Given the often dramatic alleviation of ADD symptoms under the control of stimulant medications, it is difficult to give credence to the notion that ADD impairments are simply due to a lack of willpower.
All of the following support the author's contention that ADD is related to the neurotransmitter pathway in the brain EXCEPT
(A) Straterra, a medication that affects the neurotransmitter pathway for norepinephrine but not for dopamine, can be effective for some ADD patients.
(B) Hundreds of studies have demonstrated that stimulant medications work effectively to alleviate ADD symptoms for 70 to 80 percent of patients.
(C) New high-resolution, three-dimensional maps of the brains of children with ADD indicate significant and specific differences of regional brain size within areas of the brain thought to control attentional and inhibitory control systems, compared with brain scans of children without ADD
(D) The dopamine theory of ADD is supported by neuroimaging studies, which confirm an inhibitory dopaminergic effect at prefrontal level.
(E) Two genes, DAT1 - a dopamine transporter gene and DRD4 - a dopamine receptor gene, have been reported to be associated with ADD by a number of scientists.
Experts: only Veritas Prep experts, please!
For years, people who have recognized that many children are inherently active have assumed that those who were particularly hyper would simply outgrow such a phase. Today some skeptics still believe that those diagnosed with ADD are simply people who lack willpower and discipline. Yet, given the progress that has been made in understanding the ADD mind, it is increasingly clear that ADD is a very real chemical impairment of the brain that persists in adulthood for 30-50% of those diagnosed as children.
For many years, what is now called ADD was perceived as childhood behavior characterized by impulsivity and an inability to sit still. In the 1970's, researchers first recognized that hyperactive children also had tremendous difficulty maintaining the attention required to complete tasks or listen to their teachers. This realization that inattention rather than hyperactivity was the principal problem led to the first major paradigm shift in understanding ADD syndrome.
Recently, there has been another major change in our understanding of ADD. Researchers have now recognized that ADD symptoms overlap with impairments in executive functions, the brain circuits that prioritize, integrate, and regulate other cognitive functions. Impairment in these functions stems from the brain's inability to inhibit impulses. The brain of a person with ADD may have difficulty forestalling the impulse to speak out of turn, the inclination to intentionally irritate a sibling (despite knowledge that such action will lead to punishment), the distraction of paperclips on a desk, or the desire to play outside before math homework has been completed.
Persons with ADD who use stimulant medications often experience improvements in executive brain functions and impulse inhibition. There is now considerable evidence that executive functions depend on neurotransmitter chemicals such as dopamine. Stimulant medications like Ritalin affect these chemicals at neural synapse sites that control crucially important executive functions. Stimulants are not without risks and side effects, and stimulants do not cure ADD. But they do alleviate symptoms while the dose of medication is active.
Much remains to be learned about how the brain's complicated neural networks operate to sustain attention. Yet it seems clear that impairment of executive functions, those brain processes that organize and activate what we generally think of as attention, are the result of the disruption of neurotransmitter pathways in the brain. Given the often dramatic alleviation of ADD symptoms under the control of stimulant medications, it is difficult to give credence to the notion that ADD impairments are simply due to a lack of willpower.
All of the following support the author's contention that ADD is related to the neurotransmitter pathway in the brain EXCEPT
(A) Straterra, a medication that affects the neurotransmitter pathway for norepinephrine but not for dopamine, can be effective for some ADD patients.
(B) Hundreds of studies have demonstrated that stimulant medications work effectively to alleviate ADD symptoms for 70 to 80 percent of patients.
(C) New high-resolution, three-dimensional maps of the brains of children with ADD indicate significant and specific differences of regional brain size within areas of the brain thought to control attentional and inhibitory control systems, compared with brain scans of children without ADD
(D) The dopamine theory of ADD is supported by neuroimaging studies, which confirm an inhibitory dopaminergic effect at prefrontal level.
(E) Two genes, DAT1 - a dopamine transporter gene and DRD4 - a dopamine receptor gene, have been reported to be associated with ADD by a number of scientists.
Experts: only Veritas Prep experts, please!
