If you’ve done any reading about autism you’ve probably come across the term ‘Restricted Interest’ or ‘Special Interest’. The Diagnostic and Statistical Manual (DSM-V), which is used to diagnose autism defines special interests as ‘Highly restricted, fixated interests that are abnormal in intensity or focus (e.g., strong attachment to or preoccupation with unusual objects, excessively circumscribed or perseverative interests)’....
https://respectfullyconnected.com/2015/02/an-insiders-view-of-special-interests/