After 27 - Hell, After 22 - It All Goes Downhill

I thought as much:

Old age is often blamed for causing us to misplace car keys, forget a word or lose our train of thought.

But new research shows that many well-known effects of ageing may start decades before our twilight years.

According to scientists, our mental abilities begin to decline from the age of 27 after reaching a peak at 22.

...The first age at which performance was significantly lower than the peak scores was 27 – for three tests of reasoning, speed of thought and spatial visualisation. Memory was shown to decline from the average age of 37. In the other tests, poorer results were shown by the age of 42.

...There is some good news, though. The report states that abilities based on accumulated knowledge, such as performance on tests of vocabulary or general information, increase until at least the age of 60.