Dr Martin Wessendorf is a neuroscientist and an associate professor emeritus at the University of Minnesota. His work focuses on how the brainstem controls the function of neurons in the spinal cord. Daniel Wang also researches the brain, with his focus on cognitive neuroscience and neurodegenerative diseases.

They are the authors of a new Frontiers in Neuroanatomy article that explores several brain circuits in four-limbed animals that are cross-wired (meaning one side of the brain connects with the opposite side of the body). It proposes a novel hypothesis about how they might have evolved.

For those who have studied neuroanatomy, you might have wondered about the brain’s cross-wiring and its evolutionary history. We’ll go over different pathways and then propose our hypothesis on why most of these contralateral (midline-crossing) pathways evolved.