The Evolutionary Mystery of Left-Handedness and What It Reveals About How the Brain Works | Brain Pickings

The Evolutionary Mystery of Left-Handedness and What It Reveals About How the Brain Works | Brain Pickings:

So what can the brain reveal about handedness? One of the first scientists to ponder the mystery of left-handedness was pioneering French surgeon Paul Broca, whom Wolman calls “the closest thing the religion of Southpaw has to a prophet.” In 1861, just two years after Darwin had discovered the principles of evolution, Broca encountered two patients who stumped him profoundly. One was an epileptic man named Leborgne but known as “Tan,” nicknamed after the only syllable he was capable of uttering. Leborgne was able to understand spoken language but couldn’t articulate his thoughts in speech — something that perplexed Broca enormously, doubly so given that one of Leborgne’s first symptoms was a weakening of function in the right side of his body, which progressed to more loss of motor control and eventually the loss of sight and some of his mental faculties.