Sixty-six years ago today, more than 70,000 10 and 11-year-old children across Scotland took an intelligence test. The results were painstakingly recorded and stowed away in a basement.
And there they stayed - largely forgotten - for the next five decades. But now they have formed the foundation of a remarkable research project which is producing valuable insights into what lies behind cognitive decline - or ageing of the brain.
Every three years, Ina Wallace is put through a range of cognitive checks by researchers at Edinburgh University. The tests include memory, mental speed, vocabulary and verbal abilities, planning and organisation.
She also re-takes an intelligence test she first encountered when she was a girl. "I was at Musselburgh school and we went into the main hall and there were long lines of desks," she said.
"I was very worried because you had to write your name. I was very concerned because the line wasn't long enough. So I do remember it very vividly."