Hospital officials trying to discover the identity of the so-called Piano Man are looking into the possibility he could be from Norway.
The unidentified man was found in a soaking wet suit
The virtuoso pianist has not spoken since being found in a soaking wet suit in Sheerness, Kent, in April.
A Norwegian speaker has been trying to communicate with the man, who is in his 20s or early 30s, after he was shown a map and pointed to Oslo.
A ship from Norway was thought to have been in the area when he was found.
The man is being cared for in a secure mental health unit in Dartford, Kent.
He stunned carers with a four-hour concert-standard piano performance after producing detailed pencil drawings of a grand piano soon after he was found on 7 April.
There have been few clues as to his identity since.
More than 200 names have been put forward and are being investigated by the West Kent NHS Trust in conjunction with the police and the National Missing Persons Helpline.
However, the man was reportedly more responsive when a Norwegian speaker was brought in, although it is understood he still did not say anything.
A spokesman for the trust told the BBC that various interpreters had been used, and Norway could "logically be looked at as an option".