There’s something deeply unnerving about having a device that can read your thoughts and emotions strapped to your head. But that’s what I’m experiencing in the media room of Emotiv, a San Francisco-based company, and I’m not sure I like it.

Emotiv has developed technology it believes could have as profound an effect on our relationship with the material world as anything since we began to use machines to improve our lives. Although this technology will first be seen next year in video games, the company is talking about extending its use to almost every aspect of our lives.

Emotiv is no fly-by-night outfit. Its founders include Allan Snyder, a renowned Australian neuroscientist. Randy Breen, the chief product officer, was previously head of development at LucasArts, the video games company of Star Wars director George Lucas.

What I’m about to experience, though, as Marco, the Emotiv technician, adjusts the headset for the shape of my head, is every child’s fantasy, and every adult’s secret dream: how to make things happen just by thinking about them. For the moment, that’s restricted to moving things about on a computer screen, but in time the technology will have much wider applications.

The prototype headset has 16 sensors that attach to various points on my head so it can pick up the complex – I hope! – electrical signals from the millions of neurons in my brain. If it sounds similar to an electroencephalogram (EEG) – the medical technique that measures the electrical activity of the brain – it is. But Emotiv has found a way of taking it out of the clinical setting and making it cheap enough for consumer use. Once the headset has read my brain’s signals, it feeds the information through a computer using algorithms developed by Emotiv and transforms those thoughts into actions.

To appreciate how revolutionary this is, think about how we interact with machines, from light switches to televisions to mobile phones to computers. Imagine being able to make these machines do what we want – turn them on or off, change a TV channel to one that suits our mood or choose which music we want to listen to on our iPods. “Our vision for the next generation of man-machine communication will not be limited to just conscious communication,” says Nam Do, co-founder and chief executive officer of Emotiv. “Nonconscious communication between man and machines will play a big part.”

For the moment, though, Emotiv is developing the technology for video gaming. There are two reasons. The first is that video gamers are early adopters of new technology and Emotiv is hoping they will help it spread. The second, as I am about to learn, is that the Emotiv technology transforms the gaming experience into something almost magical: you can make things happen, move things, shoot things, kill people even, almost anything really, just by thinking about it.

Emotiv is developing three different applications. The first is called Expressiv. With this function if I wink, an avatar on the computer or video-game screen winks too, although she looks rather more seductive than I do. If I smile, she smiles; if I frown, she frowns. I suspect if I were to raise my arm, so would she. At the moment with video games, if you want an avatar to smile, you have to type in a symbol for smile. This will allow game players a far greater level of freedom – a bit like using a Nintendo Wii but with nothing in your hand.

The second function is called Affectiv. This measures my emotions, such as my level of excitement or calmness and represents these as a graph visible on the screen. Measuring this allows the game to respond to my emotion, for instance by ramping up the action if I appear to be bored. The pulsating graph is, in my normal state, fairly flat, but jumps wildly, registering my embarrassment, when Do, laughing, asks me “an inappropriate question: “Who is your favourite male porn star?”

The third is called Cognitiv, and it detects my conscious thoughts, which allows me to move and manipulate objects on a screen, for instance pushing a cube away from me or making it rotate. It does this by taking a reading for 10 seconds of my brainwaves in a resting state, then for 10 seconds as I concentrate hard on making the cube do what I want. The more you repeat the process the more the computer learns and the easier it becomes.

The incredible thing is this: it works. When I put it to use in a Harry Potter video game adapted to take advantage of the technology, the effect is astounding. While I make Harry move by using a joystick, I can make him perform certain actions, like lifting a huge stone or throwing fire sticks, simply by thinking him to do it. It’s stunning.

“We’ve had 12-year-olds playing the game and they really think it’s magic,” says Le. “They really believe they are Harry Potter making these things happen.”