New research on choice and decision making shows that middle-aged adults make the most sound risk assessments.

Good risk assessment and risk evaluation seems to follow an inverted U-shaped curve over the course of a lifetimes, new research says.

The young are notorious for taking dramatic risks—unintentional injuries are the number one cause of death for men under the age of 45—but a new study from of the University of Sydney in Australia shows that decision-making skills also seem to dwindle in old age.

The study shows that middle-aged adults are the most adept at assessing risk to make the best decisions. As we age, we appear to lose that ability.

Big Decision Ahead? Let Your Subconscious Decide

Agnieszka Tymula and colleagues studied 135 healthy urban dwellers between the ages of 12 and 90 to estimate their individual attitudes toward risk and ambiguity. The subjects were put through gain and loss trials to measure their views on risky or ambiguous financial decisions.

One example was giving subjects the choice between losing $5, or taking a risk that would either leave them $8 in debt or cost them no money at all.

In some of the tests, older adults lost more than 46 percent of expected possible earnings. Young adults and middle aged adults lost less than 10 percent, on average. Adolescents, however, lost an average of 20 percent.

Researchers say the difference is linked to consistency in choices when it comes to potential losses and gains—elders were too cautious when there was more to gain, and less cautious when there was more to lose.

The older adults in the study were pre-screened and deemed to be in peak mental health, based on intelligence testing, and researchers say that there was clear evidence that the older adults fully understood the tests.

“Despite this, essentially all of them showed striking and costly inconsistencies in their choice behavior,” researchers concluded in the study, published in the journal Proceedings of the National Academy of Sciences. “This suggests that models and policies must begin to take these features of healthy elders into account.”

Why our thinking skills tend to gradually decline as we age remains a mystery.

Earlier this month, a study was released showing that high levels of omega-3 fatty acids don’t protect against cognitive decline. Another showed that even the best drugs on the market used to treat early stage dementia only have short-term benefits.

New Omega-3 Study Shows No Brain Benefits for Senior Women

Neurologists say the best way to stay mentally astute is to challenge your brain on a regular basis, whether by learning a new skill or just by doing a daily crossword puzzle.