Scientists challenge a 70-year-old “lizard brain” myth

Scientists challenge a 70-year-old theory that describes human brain evolution as a simple struggle between reason and emotion. The "lizard brain" model, which views the brain as having a newer, rational section and an older, instinct-driven part, is being questioned by researchers. Assistant Professor Nabil Imam, from Georgia Tech's School of Computational Science and Engineering, explains that there is a more complex history behind brain evolution.

Imam and his colleagues explored brain evolution in terms of wiring rather than stacking newer regions on top of older ones. By comparing biological brains and artificial neural networks, they found that evolution might involve allocating limited brain space among competing wiring strategies. The study suggests that brain regions are not evolving independently but rather, they expand and contract together as coordinated networks.

The researchers examined the organization of both biological brains and artificial neural networks and found evidence for a tug of war between two fundamentally different neural organizations that are established even before birth. This finding could help explain the long-standing puzzle in brain evolution and potentially lead to new ways of building AI systems that use less data and energy.