Magic mushrooms are known to have been used for thousands of years, for medicinal, ritualistic and spiritual purposes. Apparently, the earliest documented evidence of magic mushrooms usage dates back to 10,000 BC, in Australia. In Europe, namely in Spain, archaeologists attested the use of magic mushrooms in the year 4000 BC. In Algeria, the evidence is a mural which shows the use of a psilocybe mushroom species, i.e. Psilocybe mairei, which is thus attested to be around 6000 to 9000 years BC.
The main ingredient in magic mushrooms which is renowned for its positive effects on our human brain is psilocybin. It is considered to stimulate an increase in neurogenesis, namely in the appearance of new brain cells.
Various forms of artwork pertaining to the indigenous Central American population suggest the fact that these people used magic mushrooms for communicating with their gods, namely for spiritual reasons. Religious myths belonging to the Mayan, Aztec and Toltec civilizations also attested the use of these mushrooms for religious purposes.
In Ancient Greece, those cults which worshipped goddess Demeter used to hold rituals which involved brews possibly containing magic mushrooms. These ceremonies were rather exclusive, in the sense that only the upper class had access to them, including Homer, Aristotle and Plato.
You can find a large inventory of lab grade magic mushroom spore varietals at Shaman Mushroom Spores.