Scientists say they have published the most detailed brain scans "the world has ever seen" as part of a project to understand how the organ works.

The aim of the project is to determine how a person's brain structure influences their talents and behaviour.Researchers involved in the so called Human Connectome Project have published the scans of 68 adults in the study.They eventually hope to scan 1,200 people and also collect details of their behavioural traits and DNA.The information is made freely available to neuroscientists in their quest to unlock the secrets of the human brain.

The project leader, Prof David Van Essen of Washington University in St Louis, told BBC News that sharing the data with the international community of researchers would spur rapid advances in brain science.We are very optimistic that as the community delves in and begins working on these data sets, they will reveal new insights into the brain circuits of healthy adults," he said.

Subjects involved in the project have their brain scanned for a total of four hours. For part of that time, they carry out a battery of tasks, which include arithmetic, listening to stories, gambling and moving parts of their body.Volunteers also engage in tests that assess their skills and abilities. In addition, DNA samples are taken.The scans are essentially a wiring diagram for each person's brain.

They show how different parts are connected by nerve fibres and also the thickness of the bundles, which is thought to be an indication of the importance or strength of a particular connection- a so-called "structural map".Scanning can also show which parts of the brain are activated for particular tasks - known as a "functional map".With all this information, researchers will be able to see if an individual's brain wiring is related to their skills, such as musicality, sociability and aptitude for science or maths.

Neural circuitry

According to Oxford University's Dr Tim Behrens, who is collaborating with Prof Van Essen, the study will "uncover which neural pathways are important in determining human behaviours".The eventual aim of the project is to understand how the healthy human brain is wired and how differences between individuals make each person unique - shaping their personalities and their capacity to think and feel.Prof Van Essen is excited by what may be revealed.