The victim of an unprovoked attack may never fully recover, say officers hunting for the perpetrators.
CCTV footage has been released of three men being sought by police investigating the assault in Brighton.
A 20-year-old was punched to the face and kicked and stamped on numerous times in the attack outside Molly Malones Irish Pub, West Street at 3.30am on October 7.
The victim had a serious head injury and was treated at Hurstwood Park Neurological Centre.
A police spokeswoman said: "The victim is still recovering from the assault and has been forced to take a year off his university course as a result.
"He may never fully recover and is still undergoing treatment. Enquiries have been on-going but we have yet to trace the offenders.
"We would like talk to the three men shown in this CCTV image to help eliminate them from our enquiries.
"One of them has a distinctive tattoo on his neck.
"We hope that this image will prompt someone to call the police with the identity of these men, or call us with any other information about the incident."
Call Sussex Police on 101, quoting serial 282 of 7/10 or Crimestoppers anonymously on 0800 555 111.
See the latest news headlines from The Argus:
- Police hunt for shoplifter with handgun after supermarket raid
- Residents plea to tackle high levels of drug dealing on three Brighton streets
- Council to run up £36k legal bill fighting i360 information case
- Danny Mac's shock at staying top of Strictly leaderboard for fourth week as he goes into semi-final
- Crunch month for future of park considered one of Brighton's jewels