This is a continuation on my posts about vitamin B6. Ray has written about B6 and how it steers tryptophan metabolism in the direction of niacin rather than serotonin. Also, high serotonin has been detected in virtually all cases of "autism" and anti-serotonergic drugs like cyproheptadine have shown great benefit in relieving symptoms. Magnesium seems to enhance the effect of B6 on serotonin and dopamine.
http://www.ncbi.nlm.nih.gov/pubmed/1844561
"...Pharmacologic use of Mg can decrease neurologic deficit in experimental head trauma, possibly by blockade of N-methyl-D-aspartate receptors. In conjunction with high doses of pyridoxine, Mg salts benefit 40% of patients with autism, possibly by an effect on dopamine metabolism."
http://www.ncbi.nlm.nih.gov/pubmed/1844561
"...Pharmacologic use of Mg can decrease neurologic deficit in experimental head trauma, possibly by blockade of N-methyl-D-aspartate receptors. In conjunction with high doses of pyridoxine, Mg salts benefit 40% of patients with autism, possibly by an effect on dopamine metabolism."