AP BIOLOGY

Detailed explanation-1: -People with ADHD have at least one defective gene, the DRD2 gene that makes it difficult for neurons to respond to dopamine, the neurotransmitter that is involved in feelings of pleasure and the regulation of attention.

Detailed explanation-2: -As you know, one trademark of ADHD is low levels of the neurotransmitter dopamine-a chemical released by nerve cells into the brain. Due to this lack of dopamine, people with ADHD are “chemically wired” to seek more, says John Ratey, M.D., professor of psychiatry at Harvard Medical School in Boston.

Detailed explanation-3: -ADHD was the first disorder found to be the result of a deficiency of a specific neurotransmitter-in this case, norepinephrine-and the first disorder found to respond to medications to correct this underlying deficiency. Like all neurotransmitters, norepinephrine is synthesized within the brain.

Detailed explanation-4: -Medications that increase dopamine Many medications for treating ADHD work by increasing dopamine and stimulating focus. These medications are typically stimulants. They include amphetamines such as: amphetamine/dextroamphetamine (Adderall)

Detailed explanation-5: -Norepinephrine and dopamine, another neurotransmitter, help people pay attention and focus in the course of their daily activities. Low levels of these chemicals in the brain may make it harder to focus, causing symptoms of ADHD.