This is a condition that is mainly experienced by Autistics in addition to their Autism. Most of the most famous autistics ie Temple Grandin, Daniel Tamnet, Steven Wiltshire, Kim Peek have now been reclassified as autistic savants. Fictional savants are Raymond Babbitt – The Rainman and Shaun Murphy from the Good Doctor.
Savant syndrome is the possession of almost superman human ability in one particular field. For Daniel Tamnet his synthesia gives him incredible numerical ability and the capacity to learn any language in a matter of days even Icelandic which has no cognates. I have written about the abilities of autistics Autistic communication and Autistic education in 2 of my books previously so if you would like to find out more please check them out on my Amazon author page Books.