Don's Home Health Mental Aging and Intelligence
We all hear about cognitive decline with age.
Einstein once said, "A person who has not made his great contribution to science before the age of thirty will never do so." It was true for him.

50% of adults over the age of 85 are afflicted with Alzheimer's disease.

On the other side of the coin,
At "The Stroke of Genius Strikes Later in Modern Life", Bruce Weinberg, a labor economist at Ohio State University.says,
"Today, the average age at which physicists do their Nobel Prize-winning work is 48. Very little breakthrough work is done by physicists under 30."

A study in 2002 examined 50 Nobel prize winners from each of the three prizes for physics, chemistry and medicine. This study recorded the age of the scientists when they had done the work that was rewarded with the prize and found that the centre points for age were: physics, 34; chemistry, 37; medicine, 40.
See Age & science: do scientists make their best discoveries during their 30s? - Open Access Week
They also say,
"Today, a large number of young PhD graduates and postdocs leave science due to uncertain career structures, low salaries and recurring short-term contracts with no prospect of a permanent position. Could we be losing talented scientists before they reach their potential? Scientific success can be attributed to several different factors including education, motivation, economics, academic culture, creativity, experience, mentoring, funding trends and a reasonable dose of luck. Any correlation between age and success should be considered with these factors in mind before reaching a conclusion. However I can't help thinking that we are losing many highly trained, talented scientists and therefore stagnating our potential for innovation."

John Goodenough, age 94, coinventor of the lithium-ion battery, just got a patent for a new battery which could revolutionize the electric car industry.
See: To Be a Genius, Think Like a 94-Year-Old - The New York Times, April 2017

Brain development:
At Life and death of neurons in the aging brain. - PubMed - NCBI they say
" Neuron death is restricted in normal aging and unlikely to account for age-related impairment of neocortical and hippocampal functions. ... It appears that the primary neurobiological substrates for functional impairment in aging differ in important ways from those in neurodegenerative disorders such as Alzheimer's disease.".

Bartzokis et al., has noted that there is a decrease in grey matter volume between adulthood and old age, whereas white matter volume was found to increase from age 19-40.
Source: "Age related changes in the frontal and temporal lobe volumes in men: a magnetic resonance imaging study." Arch. Gen Psychiatry: 58, 461-465 (2001)

To Be a Genius, Think Like a 94-Year-Old - The New York Times, April 2017
How Your Brain Changes with Age - Canyon Ranch
Adult Brain Cells Do Keep Growing
Can you grow new brain cells? - Harvard Health
Aging Brain Facts - Do You Get Smarter as You Age
Sandrine Thuret: You can grow new brain cells. Here's how | TED Talk |

last updated 13 Apr 2017