They flatline the emotions. The things that make one depressed no longer cause a negative (or positive) emotional response. One still has the same thoughts - but they no longer invoke a feeling. By the same token, they may well allow the negative (perceived or actual) material to resurface with avengence - but no longer does this cause the person concern.
And then they load their pistols and go shoot everyone in the school. It doesn't strike them as a "bad" thing to do. Ask the kids who shot-up Columbine High in Colorado.
I don't understand completely... So How does it flatline the emotions? So does it work by stopping the reuptake of seretonin which makes you feel better or does the flatlined emotions just not bother you as much and therfore the seretonin just stays longer...
How does its mode of action differ from lets say a drug that did the same thing on seretonin as coke does on Dopa? Id use MDMA as an example instead of coke but im not sure it stops the reuptake of seretonin but im pretty sure coke works by stopping the reuptake of neotransmitter... Try and follow that if u can.
The actions of serotonin are not as simple as you make them out to be (i.e. increased serotonin activity = "makes you feel better"). There are 7 families of serotonin receptors, each with their own sub-receptors. These receptors act on various parts of the brain and some of them outside of the brain in the stomach and PNS. Some of these receptors act as auto-receptors, both somatodendritic and terminal. Blocking VMAT2, the monoamine reuptake transporter, increases activity at all of these sites, leading to a wide array of effects. Autoreceptor agonism for instance decreases the amount of Ca2+ allowed into the cell, thereby reducing the amount of synaptic vesicles released, and thus the amount of neurotransmitter reaching the post-synaptic density. So, it is not as simple as increased serotonin = increased happiness.
As for your example of MDMA. The pharmacological actions of MDMA are more widespread than an SSRI. Both MDMA and SSRIs tend to have an antagonist effect on the serotonin transporter (VMAT2) responsible for reuptake from the synaptic cleft. However, unlike SSRIs, MDMA also has inhibitory effects on the DA (dopamine) transporter. Cocaine inhibits the reuptake transporter proteins for DA, 5-HT (serotonin) and NE (norepinephrine).
Many 5-HT reuptake inhibitors also have inhibitory effects on NE transporters in the presynaptic neuron, sometimes by mistake (because of the other monoamine neurotransitters that use VMAT) and in more recently developed pharmaceuticals on purpose. Some tests show that blocking the reuptake of both NE and 5-HT decreases anxiety and depression with a less sever side-effect profile, though this is still up for debate.
when your neuron gets stimulated, it shoots out a NT into the synapse between two neurons. These land on sights and trigger an excitatory response then return into the synapse. They are then 'recycled' or 'reuptaken'. SSRIs block some of the recycling. Because of this your little seros are floating around having a gay ol time, but causing a little more of a rucuss because there is more of a chance of them hitting the receptor to trigger a full electric response in the dendrite/soma.
SO BASICALLY : you are increasing stimulation in your serotonin nerves. Think about looking at something. All of your eye neurons are transmitting the different colors at every point on your eye. An SSRI will make those a little more consistant! LSD is a good example of an extreme of this effect. Your neurons are having such a party that they are transmitting things so fast and wildly, sometimes even outside where they should be. So trees wobble, things are bright, and your thoughts are also getting a jump.
So you can see, a depressed person is not feeling life. By giving him some more amps the theory is life will connect with him more
MDMA and amphetamines do above, in higher quantity, but they also stimulate pumps. So they increase NT concentration while pumping a shitload of new ones in :P = fun fun fun. and why people on MDMA find it easy to bond. Everything they are feeling is enhanced, and all humans have a desire to love socially :P