Companies could monitor your brainwaves to test ads

Companies will soon be able to test public reaction to advertisements, music and films before they are released by monitoring the brain signals of a select group as they watch a trial.

So say psychologists who unveiled the results of an unusual set of experiments into so-called neural signals.

Their idea is that by scanning brain activity in just a few individuals who watch a test commercial or television programme, this will predict how a wider audience will also react to it.

Reporting in the journal Nature Communications, a team led by Jacek Dmochowski at Stanford University in California asked 16 volunteers, aged 19 to 32, to watch television as their brain signals were recorded.

They watched the 2010 premiere episode of the popular series The Walking Dead and a set of commercials which first aired in American football's Super Bowl in 2012 and 2013.

The volunteers wore electroencephalography (EEG) sensors to monitor electrical activity in the brain. They were also scanned by functional magnetic resonance imaging (fMRI), which maps brain activity by pinpointing cerebral blood flow.

What emerged was a strong correlation in the pattern of signals, showing the individuals were all focused - "engaged" - in what they saw. Their level of interest matched the response of the wider public to the show and to the commercials as measured by Twitter and the Nielsen TV audience rating.

Of course, to be focused on something does not necessarily reveal whether you liked it or not. But the experiments with the Super Bowl ads provided a clue.

Hugely expensive commercials for the Super Bowl are usually followed up with lots of research to see whether the ads were a hit with the public or not.

"In the Super Bowl study, we observed a strong relationship between the amount of neural agreement in our sample and the popularity rating of a given ad," Dmochowski said.

After being fine-tuned, neural signalling could be a useful tool for predicting audience response, said Dmochowski.

A common marketing technique today is to try out a prototype product or new idea - including political - on a panel chosen to represent the audience which is being targeted.

The flaw, though, is that individual responses can be muddied by self-reporting, poor verbal skills or group pressure - so data that comes direct from the brain could be invaluable.