Question

write about 3 drugs and how they specifically affect the brain. Examples include opioids, cocaine, alcohol, nicotine, marijuana, amphetamines. How severe is the withdrawal from these drugs? What happens within the brain once someone is addicted?

Answer 1

1. Cocaine: Cocaine increases levels of dopamine in brain circuits. Normally, dopamine recycles back into the cell that released it, shutting off the signal between nerve cells. However, cocaine prevents dopamine from being recycled, causing large amounts to build up in the space between two nerve cells.

2. Alcohol: Alcohol acts on the receptor sites for several neurotransmitters such as GABA, glutamate, and dopamine. Alcohol’s activity on the GABA and glutamate sites results in the physiological effects associated with drinking, such as a slowing down of movement and speech. Alcohol’s activity on the dopamine site in the brain’s reward center produces the pleasurable feelings.

3. Nicotine: Nicotine in the form of smoke is rapidly absorbed into the blood and starts affecting the brain within seconds. This causes the release of adrenaline, the "fight or flight" hormone. Nicotine also the dopamine reward pathways in the brain that other drugs of abuse do, although to a lesser degree.

Please post the other questions separately as we are supposed to answer just one question or four sub parts of the same question.