What part of the brain does hallucinogens affect?

Answer 1

LSD effects the entire brain, and actually increases total brain activity. Effects of LSD are perceived most strongly in the frontal lobe, visual and audial cortices (located in the front, back, and side of the brain respectively).

Answer 2

It depends on the particular drug in question, but allmost all drugs can be categorised in one of several classes, based on their effects and the way they work. Most drugs work on the neurotransmitter Dopamine, either directly or indirectly. Dopamine is what causes the pleasure feeling when it's stimulated, and it is released by the brain in order to reward itself for "good behaviour", such as sex or physical excercise (the so called "runners high" is caused by the release of Dopamine after intense excercise) which is why drugs that work on Dopamine can be so addictive, especially when they are short acting and thus causing a short but more intense release of Dopamine (Tobacco and Cocaine are short active and work on Dopamine). In extreme cases, very heavy and prolonged use of some drugs can cause permanent alterations in the brain on specific neural pathways. Meth is one such drug of which cases are known of people who have damaged their Dopamine pathways after intense and prolonged usage. However, in most causes and with the majority of different drugs there is no actual change in the brain or only temporary and reversible (in the form tolerance).

Answer 3

The brain. LSD get's it effects by binding to Serotonin receptors in the brain.