In an unnamed primary school classroom in China the lesson is all about colours. But the colours aren’t on the blackboard. They are lighting up on the kids’ foreheads.

The children are part of a trial, reported earlier this year, in which each is fitted with a brainwave-reading headset, made by Boston-based startup BrainCo, that measures how focused they are on their school work. A small light on the device tells the teacher if those young minds are straying. Blue means relaxed, yellow means focused and red means very focused.

Neat. And maybe the headband, which is called Focus 1, is a useful teaching tool. But the experiment also has a darker side.

BrainCo has said it aims to “build the world’s largest brainwave database”, a claim that has some neuroscientists worried. Their fears centre on a tsunami of research that is delving deep into people’s minds and get ever closer to knowing what they are feeling – and even thinking.

It is science that threatens what is perhaps the last frontier of privacy: our minds.

In July, tech guru Elon Musk announced his company Neuralink had built a tiny Bluetooth-enabled brain chip that he hopes will be trialled next year in people with paralysis, to let them control a computer cursor with their thoughts.

Musk’s implant consists of thousands of flexible thread-like electrodes that are inserted, robotically, via a small incision in the skull into the outer layer of the brain. It’s called a brain-computer interface and harvests the same electro-encephalogram (EEG) signals as the Chinese kids’ headsets, albeit with much greater resolution.

The tech could be life-changing, but it’s also been racking up serious cachet in brain-reading circles.

Read the full story in the Age newspaper here

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