The accenting of prefixes is also a well-attested method of signaling contrast in English. This case may seem particularly strange to Spanish students, since it is very rarely used in Spanish.
(44) 
When you see the airy and comfortable rooms heard of, you find they are stuffy and uncomfortable (Tadhg Hynes -Dublin, Ireland- reading a story by Thomas Hardy).
(45) I don’t know whether this is at a conscious level or at an unconscious level (unknown speaker).
(46) The most mysterious thing about acting to non-actors is whether you become someone else (Mark Lawson; London, UK).
(47) I don’t like historical novels, I won’t try an anti-historical novel (Richard Flanagan; Tasmania, Australia).
As can be observed in the examples, the word with the accented prefix has always a counterpart without the prefix which has been uttered before (comfortable-uncomfortable, conscious-unconscious, etc.).