HOW WE LEARN

Computers learn, but they will not hold a candle to humans for the foreseeable future, according to this expert overview of learning.

Dehaene (Cognitive Psychology/Collège de France (Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts, 2014, etc.) emphasizes that a fly can learn and that a newborn’s brain contains a great deal of information thanks to several billion years of evolution. Unfortunately, he writes, “evolution adapts each organism to its ecological niche, but it does so at an appallingly slow rate.” However, “the ability to learn…acts much faster; it can change behavior within the span of a few minutes, which is the very quintessence of learning.” Never mind our opposable thumb, upright posture, fire, tools, or language; it is education that enabled humans to conquer the world. “We are not simply Homo Sapiens, but Homo docens—the species that teaches itself,” writes the author. Short-term memory of a literate person is almost double that of someone who has never attended school. IQ (a supposedly fixed concept) increases several points for each additional year of education. In the first of the book’s occasionally dense but mostly accessible sections, Dehaene defines learning as simply forming an internal model of the outside world. In the second, he describes how learning occurs. A computer leaves the assembly line as a blank slate, but a newborn’s brain already possesses circuits enabling it to generate abstract formulas and the ability to choose wisely from those formulas according to their plausibility. The third section defines “four pillars of learning” that make our brain the most effective learning device. “Attention” carefully selects relevant signals. "Active engagement" (i.e., curiosity) generates hypotheses. “Error feedback” corrects the mental model when the world violates our expectations. Finally, “consolidation,” which involves sleep as a key component, transfers knowledge to long-term memory, freeing neural circuits for further learning. The best educators, whether parents or teachers, follow these principles, and the author urges their general adoption.

Dehaene’s fourth insightful exploration of neuroscience will pay dividends for attentive readers.