This method can help uncover a person's mental state and determine what sort of information is being processed before it reaches conscious awareness.
The discovery of this new window into the brain has provided scientists with a means to develop a more accurate model of the inner functions of the brain.
Led by Stephen Jose Hanson, a professor of Psychology at Rutgers, the study has provided direct evidence that a person's mental state can be predicted with a high degree of accuracy through functional magnetic resonance imaging (fMRI).
The research has also suggested that a more comprehensive approach is needed to map brain activity, and that the widely held belief that localized areas of the brain are responsible for specific mental functions is misleading and incorrect.
In their analysis of global brain activity, the researchers found that different processing tasks have their own distinct pattern of neural connections stretching across the brain, similar to the fingerprints that distinctively identify each of us.
However, instead of being a static pattern, the brain is able to arrange and rearrange the connections based on the mental task being undertaken.
"You can't just pinpoint a specific area of the brain, for example, and say that is the area responsible for our concept of self or that part is the source of our morality.
It turns out the brain is much more complex and flexible than that. It has the ability to rearrange neural connections for different functions. By examining the pattern of neural connections, you can predict with a high degree of accuracy what mental processing task a person is doing," said Hanson.
The findings open up the possibility of categorizing a multitude of mental tasks with their unique pattern of neural circuitry, and also represent a potential first, early step in developing a means for identifying higher-level mental functions, such as 'lying' or abstract reasoning.
They potentially also could pave the way for earlier diagnosis and better treatment of mental disorders, such as autism and schizophrenia, by offering a means for identifying very subtle abnormalities in brain activity and synchrony.
The findings provide a more accurate direction for mapping the effective connectivity of the brain.
Known as the Connectome Project, the goal of researchers involved in the work is to provide a complete map of the neural circuitry of the central nervous system.
The study involved 130 participants, each of whom performed a different mental task, ranging from reading, to memorizing a list, to making complex decisions about whether to take monetary risks, while being scanned using fMRI.
By analyzing the participants' fMRI data against classifications developed from the fMRIs of other individuals, the researches could identify which of eight tasks participants were involved in with more than 80 percent accuracy.
The researchers could also identify what class of objects (faces, houses, animals, etc.) a person was viewing before he or she could report that information by analyzing the pattern of brain activity at the back of the brain where information is processed and then conveyed towards the frontal regions associated with awareness.
"What our research shows is that if you want to understand human cognitive function, you need to look at system-wide behavior across the entire brain. You can't do it by looking at single cells or areas. You need to look at many areas of the brain to even understand the simplest of functions," explained Hanson.
The study appears in a forthcoming issue of Psychological Science.