A WORKER who was allegedly hit on the head by a heavy metal chain 10 years ago while working on the construction of the Mass Transit Railway is now suffering from amnesia, the High Court heard. Mr Pang Hong-wood, who was 28 at the time, is claiming damages for injuries against the main contractor, Okumura-Shimizu, and the sub-contractor, Mr Chu Wai-man of Dowel Construction Company. Doctors for the plaintiff had diagnosed Mr Pang as suffering from retrograde amnesia, being unable to recall simple facts, his age, address or the seasons of the year which was consistent with the injury suffered. But doctors of the defendants claim Mr Pang is a malingerer and was not badly injured. The only witness to the incident said Mr Pang was knocked unconscious. But his employers claimed he slipped and hit his head on the rail track. The hearing continues.