A strong relationship exists between positive behavior traits and the wiring of your brain, a new Oxford University study finds. While some brains appear to be wired for a lifestyle that includes education and high levels of satisfaction, others appear to be wired for anger, rule-breaking, and substance use, the research suggests.

A single positive-negative axis linked “lifestyle, demographic, and psychometric measures to each other and to a specific pattern of brain connectivity,” wrote the study authors.

The Human Connectome Project, a National Institutes of Health-funded venture which will conclude this year, seeks to create comprehensive diagrams of the brain circuitry for 1,200 adults. To conduct this work, scientists use noninvasive neuroimaging equipment, including customized head coils and cutting-edge MRI hardware. The splendid maps that result show the trajectories of fiber bundles coursing through white matter and functional connections between gray matter regions.

Study participants include a high proportion of twins and their non-twin siblings to help the researchers understand whether brain circuits are inherited. At the same time, all participants have had their genomes mapped so genetic influences on brain wiring can be evaluated. The participants also completed questionnaires and tests measuring behavior and demographic traits.

Importantly, the data is made freely available for scientists around the world to use in their own private studies.

Positive-Negative Axis

For one such study, researchers at Oxford University's Centre for Functional MRI of the Brain accessed completed brain maps from 461 Human Connectome Project participants. Using this data, the team created a general or population-average map of connections among 200 regions of the brain. Then, the team looked at how much, in separate participants, those regions communicated with each other. Essentially, they created a map of the brain’s strongest connections for each participant.

Finally, the team performed a mathematical analysis to compare this imaging data with some old-fashioned facts and figures — specifically, 280 measurements of behavior traits and demographic information. What did this comparison reveal?

Most people fall into one of two groups along an axis created from the two datasets, the scientists discovered. Those with brain wiring patterns at one end of the scale scored highly on measures most people consider "positive," such as life satisfaction, income, vocabulary, memory, and years of education. Similarly, those with patterns at the other end of the scale had high scores for traits most people view as "negative," such as anger, rule-breaking, substance use, and poor sleep.

This positive-negative axis, as the scientists refer to it, apparently spells the difference between a happy life and discontent. With additional studies the team may one day discover why most of us can be found at either end of this scale.

Source: Smith SM, Nichols TE, Vidaurre D, et al. A positive-negative mode of population covariation links brain connectivity, demographics and behavior. Nature Neuroscience. 2015.