The 650 skeletal muscles in the human body contract when they receive signals from motor neurons, which are triggered from a part of the cell called the sarcoplasmic reticulum. Motor neurons tell your muscles to contract and the better you become at having those signals tell your muscles to contract, the stronger you can get.
Amphetamine like adderall,vyvanse are weaker because they do not have a methyl group. adding a methyl group to amphetamine makes N-Methylamphetamine. a Methyl group makes it much more potent therefore you need less to get high and it is much more powerful.
for more info go to
https://psychonautwiki.org/wiki/Adderall
https://psychonautwiki.org/wiki/Meth
<span>the answer is clinical psychologists</span>
