Activity observed in the brain when using a "mind machine" is similar to how the brain learns new motor skills, scientists have found.

Participants' neural activity was recorded by using sensors implanted in their brain, which were linked to a computer that translated electrical impulses into actions.

The researchers believe people will be able to perform increasingly complex tasks just by thinking them.

The study is published in PNAS journal.

The subjects in the study moved from thinking about a task to automatically processing a task, in a similar way to how other motor movements are learnt - like playing the piano or learning to ride a bicycle.

This was shown by the areas of neurons that were active in the brain, which changed as subjects became more adept at a mental task.

Scientists analysed the results of a mind control task on a brain-computer interface (BCI) of seven participants with epilepsy.

Mind control

They were asked to play a computer game where they had to manipulate a ball to move across a screen - using only their mind.

Recent studies using BCIs have shown that our minds can control various objects, like a robotic arm, "but there is still a lot of mystery in the way we learn to control them", said Jeremiah Wander from the University of Washington in Seattle, US, who led the study.

"It's similar to learning a new motor task, but in other ways it's really different as there is no sensory feedback coming to your brain."

He believes his research could help individuals master more advanced levels of mind control.

"If we slowly work to add in more and more difficulty, we can push the limits on how complex the devices are that people can control.

"We now have an understanding from the brain signals themselves, as to whether or not a user has developed proficiency with the current level of complexity of a task," he explained.

Image caption Areas that have been implicated in motor movements and abstract learning showed less activation as subjects became adept at tasks

Ian Daly from the University of Reading, UK, who works on non-invasive BCIs, said that the study would help other scientists build BCIs that are more useful for analysing the different interactive paths of the brain.

"We expect from previous reports in the literature that there's a similar response in the brain when you make a movement and when you imagine a movement.

"The novelty of this study does not come from discovering the area is involved in learning. What is novel is studying the learning effect of subsequent trials in a BCI context," Dr Daly told BBC News.

"This paper highlights that neural networks of the brain are not static; they are dynamic and they change over time."