Brain Repurposes Itself to Learn Scientific Concepts

The human brain was initially used for basic survival tasks, such as staying safe and hunting and gathering. Yet, 200,000 years later the same human brain is able to learn abstract concepts, like momentum, energy and gravity, which have only been formally defined in the last few centuries.

New research forthcoming in Psychological Science, a journal of the Association for Psychological Science, investigates how the brain is able to acquire brand new types of ideas. Scientists at Carnegie Mellon University, Robert Mason and Marcel Just, used neural decoding techniques developed at CMU to identify specific physics concepts that advanced students recalled when prompted. The resulting brain activation patterns indicated that students’ brains used ancient neural systems in the same way, and the patterns revealed how the new knowledge was formed — by repurposing existing neural systems.

According to Mason and Just, the findings could be used to improve science instruction.

“If science teachers know how the brain is going to encode a new science concept, then they can define and elaborate that concept in ways that match the encoding. They can teach to the brain by using the brain’s language,” said Mason, a senior research associate in the Dietrich College of Humanities and Social Sciences’ Department of Psychology.

Mason and Just, the D. O. Hebb University Professor of Psychology, recruited nine advanced physics and engineering students to participate in the study. Each student’s brain was scanned at CMU’s Scientific Imaging and Brain Research (SIBR) Center while they were shown a set of 30 familiar concepts, such as gravity, entropy, inertia, refraction and velocity.

Using a machine learning program, Mason and Just were able to identify which of the 30 concepts a student was thinking about based on unique brain activation patterns. They also could break down the patterns into the different neural pieces used to build the full concepts.

Brain activation associated with physics concepts (image courtesy of Carnegie Mellon University).

The research showed how learning physics concepts is accomplished by repurposing neural structures that were originally used for general everyday purposes. More specifically, the brain is able to learn physics concepts because of its ability to understand the four fundamental concepts of causal motion, periodicity, energy flow, and algebraic (sentence-like) representations.

Brain systems that process rhythmic periodicity when hearing a horse gallop also support the understanding of wave concepts in physics. Similarly, understanding gravity involves visualizing causal motion, like an apple falling from a tree; energy flow uses the same system as sensing warmth from a fire or the sun; and understanding how one concept relates to others in an equation uses the same brain systems that are used to comprehend sentences describing quantities.

“This is why humans have been able to move ahead and innovate — because we can use our brain for new purposes,” Just said. “Human brains haven’t changed much over a few thousand years, but new fields like aeronautics, genetics, medicine and computer science have been developed and continuously change. Our findings explain how the brain is able to learn and discover new types of concepts.”

This work was supported by Office of Naval Research Grant N00014-131-0250.