Scientists hope to record our dreams after successful experiments using brain implants

A system which could one day allow scientists to record people's dream has been developed.
In a remarkable breakthrough which would allow researchers a unique insight into the human mind, a dream recorder that could interpret electronic data is planned.
Experiments in which volunteers had electrodes surgically implanted into their brains has so far allowed the scientists to 'read' their minds, said Dr Moran Cerf.
He said: 'We would like to read people's dreams.  It would be wonderful to read people's minds when they cannot communicate, such as people in comas
In tests on 12 epilepsy patients, electrodes recorded the activity of neurons in the part of the brain called the medial temporal lobe, which plays a role in memory retention.
With practice, the volunteers were able to control the appearance of 'hybrid' images consisting of one picture superimposed on another.
On cue they could quickly make a particular image, such as Marilyn Monroe or former US president George Bush, 'fade in' or 'fade out'.
During the tests, patients worked out their own strategies for conjuring up the right images.
Some simply thought of the picture, while others repeated the name of the image out loud or stared at a particular aspect of the image.
All the participants quickly mastered the task and were successful in around 70 per cent of trials.
Dr Cerf, from the California Institute of Technology, who worked on the research reported today in the journal Nature, said: 'The patients clearly found this task to be incredibly fun as they started to feel that they control things in the environment purely with their thought.
'They were highly enthusiastic to try new things and see the boundaries of 'thoughts' that still allow them to activate things in the environment.'
Scientists have previously used the activity of neurons in the brain to control a cursor on a computer screen.
This was also achieved by the Caltech team. By thinking of individual images, the volunteers were able to move a cursor up and down and even play a computer game.
But Dr Cerf said the team wanted to go a step further and 'tap into the competition for attention between thoughts that race through our minds'.
The 'hybrid' images experiment did just that - by allowing two mingled images to compete for dominance in the brains of the volunteers.
In each session, a participant was asked to 'fade in' a 'target' image and 'fade out' a competing 'distractor' image.
Even in cases where the 'distractor' image made up 90% of the whole picture, the volunteers were able to seize upon the target in their mind and 'pull it back', said Dr Cerf.