Don Triplett, first person diagnosed with autism, dead at 89

Donald Triplett, the first person to be diagnosed with autism and known in scientific journals as “Case 1,” has died at the age of 89.

The real-life “Rain Man” who had perfect pitch, uncanny memorization skills and could do complex mathematical equations in his head in seconds, died Thursday.

Triplett, who would have turned 90 in September, worked at the Bank of Forest in Scott County for 65 years.

His journey was documented in the book “In a Different Key,” which led to a documentary film and a BBC news magazine installment. He was also cited in numerous medical journals.

In 1938, Triplett was examined by Austrian child psychiatrist Leo Kanner at Johns Hopkins Hospital in Baltimore, who was stumped at first by the child’s symptoms, according to the Encyclopedia Britannica.

Kanner checked Triplett out a number of times and he finally made the diagnosis of autism after Triplett’s parents sent the doctor a detailed 22-page letter detailing his aptitudes and behavior. 

The letter remains a key reference point for those who study the disorder.


A photo of Donald Triplett.
Donald G. Triplett, who worked at a bank in Forest, Mississippi, for 65 years and was the first person ever diagnosed with autism, died at age 89.
Facebook/Senator Tyler McCaughn

A photo of Don Triplett with two filmmakers.
Triplett’s journey was documented in the 2022 film “In a Different Key” by filmmakers Caren Zucker and John Donvan.
Facebook/In A Different Key: The Movie

The bank CEO Allen Breland, who has been at the bank 36 years, called Triplett a “remarkable individual.”

“He kept things interesting,” Breland told WLBT-TV.

Though he came across to newcomers as sometimes socially awkward, strange and obsessive, Triplett had an otherworldly facility with numbers.

“He was in his own world,” Breland said, “but if you gave him two three-digit numbers, he could multiply them faster than you could get the answer on a calculator.”

Oliver Triplett, Triplett’s nephew, told The Times-Picayune/The New Orleans Advocate that his uncle offered hope to parents of children who are different.

“They can see Don and a community who embraced him,” he said. “As a whole, Forest encouraged him and accepted him. It gives people who have children on different levels of the spectrum hope that their children can live happy and full lives.”