Sixty-five-year-old Tom North didn't believe he had a memory-loss problem and was becoming angry and frustrated with people telling him he did.
His wife, Edwina, and his former work colleagues had sensed he had Alzheimer's before he acknowledged it.
"I was still working and people at work were telling me that things were wrong," he said.
"And I started arguing with my wife."
It was Mrs North who eventually contacted Alzheimer's Australia WA, which offered support and the chance for her husband to take part in a pilot program of the Ashby Memory Method.
"Once I started it, I realised I did actually have Alzheimer's," Mr North said.
"The program took me from being miserable and argumentative to being normal again."
The program also sharpened his memory.
Mr North is now helping out one day a week at the Kanyana Wildlife Rehabilitation Centre in Lesmurdie.