In an interview with KTSF 26, a Chinese-language TV station serving Northern California, Kao, 75, said he sometimes finds it difficult to talk.

"I myself am not very good now," the former vice chancellor of the Chinese University of Hong Kong said yesterday from his home near San Francisco. "Saying what I want to say from my heart, it's very difficult to do."

Kao, who holds British and US nationalities and has a home in Hong Kong as well as the United States, said he is "very happy" to receive the award.

The Shanghai-born scientist, who was educated in Hong Kong and Britain, will attend the Nobel ceremony in Stockholm in December, his wife Gwen Kao May-wan said.

She said she found it hard to come to terms with her husband's progressively worsening condition.

"I was under a lot of pressure, because I knew what this person was like before," she said. "This disease has changed him, it is like he's gone. [I] had cried for some time. Now [I am] used to it. I know this person was not the same person as before."

Kao is still physically fit, and is capable of taking care of himself and playing tennis with her regularly.

Former Chinese University vice chancellor Professor Ambrose King said at a party to celebrate Kao's award on Wednesday: "It would be good if the award came a year earlier. However, it is still not too late for him."

Meanwhile, the couple have decided to donate part of the US$700,000 (HK$5.46 million) prize money to the elderly center of St James' Settlement in Hong Kong and an Alzheimer's association in the United States, according to the China News Service.

St James' Settlement has yet to receive confirmation of the donation, but welcomed the new. Its chief executive, Michael Lai Kam-cheung, said the organization might establish a Kao-nominated foundation, or name a building after him.

BEATRICE SIU, AGENCE FRANCE-PRESSE