This will enable a person to see films and play video games in which they smell, taste and perhaps even feel things.

 

The patent - based only on a theory, not on any invention - marks the first step towards a "real-life Matrix", the British science weekly New Scientist says in next Saturday's issue.

  

In the sci-fi film of that name, cyber-reality is projected into the brains of people via an electrode feed at the back of their necks.

  

In Sony's patent, the technique would be entirely non-invasive - it would not use brain implants or other surgery to manipulate the brain.

 

The patent has few details, describing only a device that would fire pulses of ultrasound at the head to modify the firing patterns of neurons in targeted parts of the brain.

  

'Prophetic invention'

 

The aim, the patent says, is to create "sensory experiences" ranging from moving images to tastes and sounds.

  

New Scientist said it was denied an interview with the inventor, who is based at a Sony office in San Diego, California.

  

"It was based on an inspiration that this may someday be the direction that technology will
take us"

Elizabeth Boukis,
Sony spokeswoman

Sony Electronics spokeswoman Elizabeth Boukis said the work was a "prophetic invention" and no experiments at all had been done on it.

  

"It was based on an inspiration that this may someday be the direction that technology will take us," she told New Scientist.

  

Independent experts said they did not dismiss the idea out of hand, although they also cautioned about the proposed method's long-term safety.

  

So far, the only non-invasive way for manipulating the brain is crude.

 

A technique called transcranial magnetic stimulation uses magnetic fields to induce currents in brain tissue, thus stimulating brain cells.

  

But magnetic fields cannot be finely focussed on small groups of brain cells, whereas ultrasound pulses could be.