From an early age, Aron Barbey was fascinated by the human mind and how our intellectual abilities emerge from the physical architecture of the brain.
“The brain is a soft, jelly-like lump of flesh that weighs about three pounds,” said Barbey. “But it can contemplate the vastness of interstellar space, the meaning of infinity, ask questions about the meaning of its own existence and about the nature of God. The brain is truly the most amazing thing in the world and, for centuries, has motivated considerable research and debate.”
Barbey began as a philosophy major in college, so it is no surprise that he is enthralled by big questions about the nature of the human mind. He earned a Ph.D. in psychology from Emory University in 2007 and joined the University of Illinois and the Beckman Institute in fall 2011. Prior to joining the University of Illinois, he worked as a postdoctoral research fellow with the National Institutes of Health. He now directs the Decision Neuroscience Laboratory at Beckman.
His research group investigates the effects of human brain damage on high-level cognitive functions, with particular emphasis on the prefrontal cortex. Studies of patients with brain damage have a long history in the neuroscience of intelligence and provide a direct way to test whether a brain region is necessary for specific intellectual abilities. However, it was only recently that the limited applicability and specificity of small sample studies of focal brain damage were overcome by Barbey and his colleagues.
In a series of landmark studies, Barbey investigated almost 200 patients with focal brain injuries and mapped the brain systems that underlie a host of high-level cognitive functions, including general intelligence, fluid intelligence, working memory, cognitive flexibility, and emotional intelligence.
The study mapping the neural architecture of general intelligence is considered one of the largest and most comprehensive analyses so far of the brain structures vital to human intelligence. The study enlisted an extraordinary pool of volunteer participants: Vietnam veterans with highly localized brain damage from penetrating head injuries.
The focal brain injuries analyzed in the study allowed the researchers “to draw inferences about how specific brain structures are necessary for performance,” Barbey said. “By studying how damage to particular brain regions produces specific forms of cognitive impairment, we can map the architecture of the mind, identifying brain structures that are critically important for specific intellectual abilities.”
A second study expanded on those findings to investigate how general intelligence is related to emotional and social aspects of intellectual function—providing the first and largest human lesion study of the brain mechanisms underlying emotional intelligence.
In both studies, researchers pooled data from CT scans of participants’ brains to produce a collective, 3D map of the cerebral cortex. They divided this composite brain into 3D units called voxels and then compared the cognitive abilities of patients with damage to a particular voxel or cluster of voxels with those of patients without injuries in those brain regions. This allowed the researchers to identify brain areas essential to specific cognitive abilities, and those that contribute significantly to general intelligence, emotional intelligence, or both.
Barbey found that specific regions in the frontal cortex (behind the forehead) and parietal cortex (top of the brain near the back of the head) were important to both general and emotional intelligence. The findings provide new evidence that human intelligence relies not on one brain region or even the brain as a whole, Barbey said, but involve specific brain areas working together in a coordinated fashion.
“In fact, the particular regions and connections we observed support an emerging body of evidence indicating that executive and social processes critically depend on the brain’s ability to integrate information across specific cortical regions,” he said.
The new findings will help scientists and clinicians understand and respond to patients with impairments in executive and social brain function, Barbey said, but the results also are of broader interest because they illustrate the interdependence of general and emotional intelligence in the healthy mind.
These studies received worldwide attention, but they are only one example of how Barbey’s group is using neuroscience evidence to investigate the architecture of the human mind. Barbey also led a collaborative team that received a grant in the first round of funding from the newly created Center for Nutrition, Learning, and Memory for a study on the role of nutrition in executive and social brain function.
“This project is a great example of the integrative, multidisciplinary, and highly collaborative approach to research at the Beckman Institute,” Barbey said. “Our project is a large-scale effort that includes collaborations between scientists here at the Beckman Institute and at Carle Foundation Hospital, where we will work with a team of physicians in the Carle Research Institute.”
Understanding the nature of the human mind is one of the greatest intellectual quests of all time and requires the combined insights not only of cognitive neuroscientists, psychologists, and clinicians, but thinkers in nearly every intellectual pursuit, said Barbey.
“Indeed, the study of the human mind has benefited from a multidisciplinary approach that investigates how the brain supports the spectrum of mental activities across a broad range of contexts—including how mental capacities emerge through evolution and development, are cultivated through experience, shaped by society and culture, and are altered through psychiatric illness and neurological disease,” Barbey said. “As the significance and scope of these issues would suggest, many fundamental questions about the nature of the human mind remain to be explored. We’ve only just begun to identify and piece together the deep and mysterious constellations of the human mind.”
Find more information on the Decision Neuroscience Laboratory.
Book Recommendation by Aron Barbey
How Intelligence Happens by John Duncan. This book reviews recent progress in cognitive neuroscience on the nature of human intelligence and advances the intriguing hypothesis that intelligence emerges from the prefrontal cortex and the property of its neurons to dynamically construct mental representations of a desired goal-state and the means to achieve it.