Orgasms could give our brains a better workout than doing a crossword puzzle or a Sudoku, a neuroscientist has claimed.

The sensation increases brain activity across the whole organ whereas a puzzle activates only relatively localised regions, said Professor Barry Komisaruk.

The academic, who published the first evidence of brain regions involved in orgasm in women almost a decade ago, also said the sensation of sexual climax blocks pain.

"At orgasm we see a tremendous increase in the blood flow (to the brain). So my belief is it can't be bad. It brings all the nutrients and oxygenation to the brain," he told The Times.

"Mental exercises increase brain activity but only in relatively localised regions. Orgasm activates the whole."

The professor, who works at Rutgers University in New Jersey, US, came to his conclusions after studying women in his laboratory at the university's Department of Psychology. He measured the blood flow to their brains as they climaxed.

The 72-year-old researcher has been studying female sexual pleasure since the 1960s. He started his experiments on rats but moved on to women in the 1980s.

But he still believes there is much to learn about sexual climax, telling the newspaper: "We know virtually nothing about pleasure.

"It's important to understand how the brain produces it. What parts of the brain produce such intense pleasure, and can we use that in some way? What would that do to depression or anxiety or addiction or pain?"