2021 完形填空（英语一）

Fluid intelligence is the type of intelligence that has to do with short-term memory and the ability to think quickly, logically, and abstractly in order to solve new problems.

It peaks in young adulthood, levels out for a period of time, and then generally starts to slowly decline as we age.

But while aging is inevitable, scientists are finding that certain changes in brain function may not be.

One study found that muscle loss and the accumulation of body fat around the abdomen are associated with a decline in fluid intelligence.

This suggests the possibility that lifestyle factors might help prevent or delay this type of decline.

The researchers looked at data that included measurements of lean muscle and abdominal fat from more than 4,000 middle-to-older-aged men and women and compared that data to reported changes in fluid intelligence over a six-year period.

They found that middle-aged people with higher measures of abdominal fat scored worse on measures of fluid intelligence as the years went by.

For women, the association may be attributable to changes in immunity that resulted from excess abdominal fat; in men, the immune system did not appear to be involved.

It is hoped that future studies could explain these differences and perhaps lead to different treatments for men and women.

Meanwhile, there are steps you can take to help reduce abdominal fat and maintain lean muscle mass as you age in order to protect both your physical and mental well-being.