Collecting user data to serve up targeted ads is Google's bread and butter, and yet the company refuses to speak publicly about how its infamous augmented eyewear could kick that business model into high gear. Still, the tightlippedness hasn't done anything to stem the speculation that Google Glass will usher in a new era of advertising.

One tech startup exploring that nascent industry is Personal Neuro, which has developed a brain-scanning electroencephalography (EEG) gadget, similar to the Emotiv EEG headset, which collects the wearer's brainwave data, analyzes it, and leverages the neural insights to create various apps.

By reading and interpreting brain signals, it can determine a consumer's mood, emotions, and taste. Now, combine that data with data from Glass features like geolocation or eye-tracking, and you've got a trove of information that could be used to deliver hyper-personalized ads to someone wearing the augmented device. It's not happening yet, but it doesn't take a huge leap to foresee it.

"The potential is incredible and hyper-targeted to the point where it is no longer advertising," Personal Neuro (PND) exec Tony Gaitatzis said in an interview on Wednesday with Dezeen. "Let's say a person goes to Barclays and geolocation recognises this. Maybe it's time to start advertising Barclays to them."

The principle is no different to how online ads already track your digital footprint and serve up, say, airline ads if you've been browsing around travel websites. But with an internet-connected wearable gadget's data deluge, your consumer profile is more detailed than ever, and creeps into the physical world.

At this point, PND's telekinesis device is marketed as a way to monitor personal health and deliver brain games. But Gaitatzis is confident that advertising will be a major use of the technology in the future—even if Google won't admit it.

"You're not allowed to say that you're going to use Google Glass as an advertising platform," he said.

But a Google patent dug up last year did suggest that a "gaze-tracking head-mounted display" could gauge users' emotions by "inferring [the] emotional state of the user while viewing the external scenes based at least in part upon the pupil dilation information." 

Meanwhile, neuromarketing is already the latest hype in the ad world; Google uses it to determine which websites to elevate in its search results, based on the sites' characteristics that would elicit an emotional response from consumers.

At this point, brands that want brain data insights to sell their products need to hire a neuromarketing firm or invest in expensive high-tech equipment. But once everyday consumers start donning data-spewing wearable computers, that barrier to entry will get much lower.

Naturally, there are all kinds of privacy concerns with this next-gen commercialism. Privacy activists worry that marketing products based on brain signals is not only incredibly invasive, it falls in an ethically murky category with subliminal advertising because it could remove the consumer's ability to think critically about the ad, or to decide to dismiss it.

But brands are eager to explore the new marketing frontier promised by wearable computing and big data. One startup, Blippar, is working to develop creative Glass apps to incorporate the eyewear's features into its ad campaigns, like "an augmented reality app that delivers content triggered by real-world interactions," Ad Week recently explained. "For instance, a wearer might see a billboard that Blippar's software recognizes, then sets off a Glass experience."

It's not a stretch to image companies offering an AR version of the 'free service in exchange for data-driven ads' model that most of the internet runs on now. Will brands offer free Glass apps in exchange for your physical location and current mood to deliver hyper-targeted ads?

I posed the question to Google this morning, and have received no comment.