VANCOUVER -- Our mental ability to perceive, analyze and respond begins to decline abruptly around the age of 24, according to an innovative new study by researchers at Simon Fraser University.

Psychology doctoral student Joe Thompson teamed up with professor Mark Blair and statistics doctoral student Andrew Henrey to analyze a huge data set gleaned from gaming records for 3,305 StarCraft 2 players to determine when human adults are officially over the hill.

Did I mention the answer is 24? Sorry about that.

StarCraft 2 is a real-time intergalactic war game set in the future that requires strategic planning, quick threat analysis and speedy responses, which the researchers suggest makes the game experience comparable to real-world experience.

Real-world threat analysis and strategic response is hard to measure, but using response times from game play, the researchers were able to effectively identify the moment that age-related declines in cognitive motor performance take hold. The study is one the first social science applications of statistical modelling for so-called Big Data, collections of information so large that they defy hands-on analytical techniques.

The project required a week of computing time on 34 million rows of data.

“The game records every action the player performs throughout the game and every action their opponent performs,” said Blair. “And unlike chess, the players don’t have to take turns, so if you can do things a little faster you literally get to make more moves than your opponent.”

Players move through a virtual environment, executing strategic moves as they land in a new visual environment about 200 times in a typical novice-level game lasting 15 minutes, so speed confers a significant advantage.

But as people age, they start to move slower. The difference in response time to a new situation or threat between a 24-year-old player and a 39-year-old player is about 150 milliseconds, taking a sizable bite out of the advantage a professional with thousands of hours of experience has over a novice, according to Blair.

Response times for players at every skill level are steady from the age of 16 to 24, where they trend sharply and steadily upward, again, at every skill level.

“There’s no need for doom and gloom,” said Thompson. “The old view that when you reach adulthood you enjoy a long period of cognitive stability and you can forget about aging until you get old. But what we are finding is that we adapt continuously throughout our lives to changing ability, so give yourself a pat on the back for just maintaining your skills. If you do, you’re showing growth and development.”

It’s not yet clear whether age slows perception, mental processing, physical response time individually or the ability to coordinate all three, said Blair.

“Age and cunning, don’t make you faster, nothing makes you faster, you are slowing down as you get older, regardless,” said Blair.

Older players compensate for their declining mental faculties by employing simpler strategies and using the game control short cuts, the researchers found.

“People in [advanced] leagues play differently depending on their age,” he said. “The older player is slower than the younger player, but they can be equivalent players, so cunning does come into play.”

Younger players appear to exploit their speed advantage by employing more complex strategies, while older players are dropping those strategies and being more efficient, he said.

The study was published last week in the online scientific journal PLOS ONE.

rshore@vancouversun.com