Can synaesthesia be acquired?
Yes. Hallucinogenic drugs such as LSD, magic mushrooms and mescaline can all produce transient forms of synaesthesia (e.g. Hartman & Hollister, 1963) although we are not aware of anyone who claims to have permanently acquired synaesthesia as a result of drug use. Other people have acquired synaesthesia after becoming progressively blind (e.g. Armel & Ramachandran, 1999).
