Scientists claim to have shed light on the neural basis of creativity by scanning the brains of accomplished pianists while they improvised on a keyboard.

Images of the pianists' brains highlighted areas that seemed to underpin their musical creativity, alongside regions that were strongly connected in pianists with the most improvisation experience.

The scans point to a network of brain regions that are involved in creative playing, including the dorsolateral prefrontal cortex, which has previously been linked to the suppression of stereotypical responses and the selection of improvised actions.

To do the experiment, the researchers had a keyboard custom made to work inside a brain scanner. The high magnetic fields generated in a functional magnetic resonance scanner meant none of the normal metal components could be used. Instead of steel strings, fibre optics were fitted to sound out the notes.

Ana Pinho, at the Karolinska Institute in Stockholm, scanned the brains of 39 professional musicians and students, most of whom came from the Royal College of Music in Stockholm. The musicians had different levels of training in classical and jazz piano.

Laid down inside the scanner, the pianists were invited to play whatever they liked, though the scientists prompted them from time to time, suggesting they use a certain scale, or play a piece that expressed fear or happiness.

The scans showed that areas of the brain involved in improvisation were less active in the more experienced pianists, perhaps because their brains were working more efficiently. Regions thought to be important for improvisation had greater connectivity in the pianists who had more experience of improvising, Pinho said.

"More improvisation training led to more automation and higher functional connectivity between regions that are important for creative playing. This greater connectivity improved the efficiency and communication between those brain regions," Pinho said at the Society for Neuroscience meeting in San Diego.

The study adds to a stock of work on the brain processes involved in forms of creativity. In 2008, Charles Limb at the National Institutes of Health in Maryland scanned the brains of jazz musicians while they improvised pieces with and without a jazz quartet. The scans revealed a distinct pattern of changes in part of the brain called the prefrontal cortex that seemed to underlie spontaneous musical composition.

Gottfried Schlaug, director of the music and neuroimaging lab at Beth Israel Deaconess and Harvard Medical School in Boston, said that while some people may be born with brains that are well suited to learning music, learning to play instruments leads to changes in the brain too.

"Improvisation is one way into understanding creativity. These tools allow us to understand what brain regions are involved in creative thought and in coming up with new ideas," he said. "Once we know what those brain regions are it might be possible to influence them. And from a societal perspective it's always important to strengthen creativity, because it is the seed for new developments and new ideas."