SAN FRANCISCO (Diya TV) — A new study from the University of Melbourne has discovered working the standard 40 hours per week could lead to a decline in cognition for people over the age of 40.

The study notes that while work can serve as a stimulation for some older workers’ brains, long hours can “cause fatigue and physical and/or psychological stress, which potentially damage cognitive functioning. This then leads to staff being absent and the implementation of something like an employee time clock app may be useful to help manage staff availability.

” For those over 40, working over 25 hours per week could impair intelligence, while working up to that produced the opposite effect.

Using data from the Household, Income and Labor Dynamics in Australia survey, which asks residents about various work-related topics, the study conducted memory, pattern, and reading tests in more than 6,000 workers over the age of 40.

Colin McKenzie, a professor of economics at Tokyo’s Keio University and an author of the paper, said that 40 is a tipping point because it’s when “most people perform less well at memory tests, pattern recognition and mental agility exercises.”

“Work can be a double-edged sword, in that it can stimulate brain activity, but at the same time, long working hours and certain types of tasks can cause fatigue and stress which potentially damage cognition,” he said.

The decline can be traced through stress caused on the job and from lack of sleep, McKenzie said. However, other factors are also in play — McKenzie hypothesizes that being a caregiver to someone can add additional stress, and creates a job on top of a job.