Oi,
MDMA is the empathy drug. It makes you feel closer emotionally to everything; my friend once asked me what she could expect from ecstasy and I simply answered: "have no expectations, but if I was to describe the effects as bluntly as possible, I'd say it's a
happy pill." Not a 'everything is alright' happy, but a 'everything is superb' happy.
From experience, disqualifying meth-bombs, MDA is the speedier, more physical version of ecstasy. Subtracting the visual effects from pupil dilation (blurry vision, glare around lights), MDA has a stronger effect on visual perception than MDMA.
I'll try to explain...
I'll start by an oversimplified description of what serotonin does in your brain. It's a neurotransmitter that's quite a bit like dopamine in the sense that it makes you feel happy. As for MDA & MDMA, both substances are mainly serotonegic in nature, meaning that they release serotonin in the brain and inhibit it's reuptake (meaning the serotonin stays in the synapses instead of being scooped up and recycled), therefore they both induce euphoria and the feeling of closeness and connection.
There is more than one variation of serotonin (5-HT) receptors in different parts of the brain and the difference between both drugs step in where MDA stimulates different variations of 5-HT receptors more efficiently than MDMA and vice versa.
Do some reading on both MDMA and MDA if you want to know more, Erowid is a good place to start and it also has lists of effects if you want to compare.
MDA:
http://www.erowid.org/chemicals/mda/mda_effects.shtml
MDMA:
http://www.erowid.org/chemicals/mdma/mdma_effects.shtml
Happy reading
