Radio listeners tune out at a greater rate during long ad breaks, according to new scientific research.

The study by Neuro Insight, a company specialising in brain-imaging technology to monitor marketing effectiveness, has found that clutter on the radio - too many ads - is making listeners mentally disengage.

Scientists studied the brain wave patterns of 60 Nova listeners and 60 listeners to the Today Network, and found they tuned out of Today advertisements at a greater rate.

The study was commissioned by DMG radio - the owner the Nova network, which plays just two ads at a time.

On Nova they found only one per cent of listeners disengaged after the first ad, while on Today 11 per cent of listeners disengaged.

By the end of the ad break on Nova two per cent had mentally tuned out, while up to 27 per cent of Today listeners disengaged by the end of the ad break, typically about six ads.

Disengagement even occurred during typically very popular programs, the study showed.

In the Hamish and Andy drive show on the Today network, at the worst point up to 36 per cent audience engagement was lost in an ad break.

Meanwhile, on the Nova drive program last year, audience engagement actually increased during the ads.

DMG Radio Australia group sales director Keith Thomas said he didn’t want to come across as bashing his rival, but said he believed there’d be revenue implications.

“I believe that consumers are already dealing with the issue of clutter by avoiding those places through flick through technology or recording devices,” Thomas told AAP.

“Ultimately, the consumer will drive media companies towards low clutter solutions, and this will accelerate that sort of thinking.

“And with that there may be a revenue impact.

“But the important thing that media and buying agencies acknowledge is that product is diminishing the effectiveness of advertising.”

Austereo, owner of the Today network, said they did not want to comment at this stage.