Words of wisdom from Harry Potter's headmaster have been invoked by a psychologist to encourage older people to strive to maintain mental agility.
Elizabeth Stine-Morrow, professor of educational psychology at Illinois University, has spent two decades studying learning methods.
She said that as much as age-related changes in the brain are beyond our control, we can compensate for them to a large extent by treating them as a 'challenge' to be overcome.
Dr Stine-Morrow said: "Minor glitches in the cognitive system can loom larger than they perhaps need to because we’ve got these preconceived ideas about what happens with ageing."
Staying mentally engaged is a matter of choice for most, she said.
Over the course of her research, Dr Stine-Murrow found that spending more time at the 'micro level' of reading enabled older readers to make up for losses in areas such as working memory and language-processing speed
She is due to discuss what she has termed her "Dumbledore hypothesis" at a conference in San Francisco on August 19th.
The Harry Potter reference is to some sage advice administered by Dumbledore in Harry Potter and the Prisoner of Azkaban: "It is our choices … that show what we truly are, far more than our abilities."