Scientists have developed an artificial intelligence system that can tell how smart a person is just by looking at a scan of the individual's brain.
Researchers from California Institute of Technology, Cedars-Sinai Medical Center and the University of Salerno in the US show that their new computing tool can predict a person's intelligence from functional magnetic resonance imaging (fMRI) scans of their resting state brain activity.
Functional MRI develops a map of brain activity by detecting changes in blood flow to specific brain regions.
In other words, an individual's intelligence can be gleaned from patterns of activity in their brain when they are not doing or thinking anything in particular.
"We found if we just have people lie in the scanner and do nothing while we measure the pattern of activity in their brain, we can use the data to predict their intelligence," said Ralph Adolphs from Caltech.
To train their algorithm on the complex patterns of activity in the human brain, researchers fed the brain scans and intelligence scores from almost 900 individuals into their algorithm, and set it to work.
After processing the data, the algorithm was able to predict intelligence at statistically significant levels across these 900 subjects, said Julien Dubois, a postdoctoral fellow at Cedars-Sinai Medical Center.
However there is a lot of room for improvement, he said.
The scans are coarse and noisy measures of what is actually happening in the brain, and a lot of potentially useful information is still being discarded.
The study was conducted as part of an ongoing quest to build a diagnostic tool that can tell a great deal about a person's mind from their brain scans.
Researchers said that they would like to see one day MRIs work as well for diagnosing conditions like autism, schizophrenia, and anxiety as they currently do for finding tumours, aneurisms, or liver disease.
"Functional MRI has not yet delivered on its promise as a diagnostic tool. We, and many others, are actively working to change this. The availability of large data sets that can be mined by scientists around the world is making this possible," said Dubois.
Intelligence was chosen as one of the first test beds for the technology because research has shown that it is very stable over time. That is, a person's IQ score will not vary much over a period of weeks, months, or years.
The researchers also conducted a parallel study, using the same test population and approach, that attempted to predict personality traits from fMRI brain scans.
The personality test they used divides personality into five scales : Openness to experience, Conscientiousness, Extraversion, Agreeableness and Neuroticism.
However, it has turned out to be much more difficult to predict personality using the method the team used for predicting intelligence.