IN the early 19th century, a French neurophysiologist named Pierre Flourens conducted a series of innovative experiments. He successively removed larger and larger portions of brain tissue from a range of animals, including pigeons, chickens and frogs, and observed how their behavior was affected.
By GREGORY HICKOK—The New York Times
His findings were clear and reasonably consistent. “One can remove,” he wrote in 1824, “from the front, or the back, or the top or the side, a certain portion of the cerebral lobes, without destroying their function.” For mental faculties to work properly, it seemed, just a “small part of the lobe” sufficed.
Thus the foundation was laid for a popular myth: that we use only a small portion — 10 percent is the figure most often cited — of our brain. An early incarnation of the idea can be found in the work of another 19th-century scientist, Charles-Édouard Brown-Séquard, who in 1876 wrote of the powers of the human brain that “very few people develop very much, and perhaps nobody quite fully.”