“Neural code” is by far the most under-appreciated term, and concept, in science. It refers to the rules or algorithms that transform action potentials and other processes in the brain into perceptions, memories, meanings, emotions, intentions, and actions. Think of it as the brain's software.
The neural code is science’s deepest, most consequential problem. If researchers crack the code, they might solve such ancient philosophical mysteries as the mind-body problem and the riddle of free will. A solution to the neural code could also give us unlimited power over our brains and hence minds. Science fiction—including mind control, mind reading, bionic enhancement and even psychic uploading—will become reality. Those who yearn for the Singularity will get their wish.
More than a half-century ago, Francis Crick and others deciphered the genetic code, which underpins heredity and other biological functions. Crick spent his final decades seeking the neural code—in vain, because the most profound problem in science is also by far the hardest. The neural code is certainly not as simple, elegant and universal as the genetic code. Neuroscientists have, if anything, too many candidate codes. There are rate codes, temporal codes, population codes and grandmother-cell codes, quantum and chaotic and information codes, codes based on oscillations and synchronies.
But given the relentless pace of advances in optogenetics, computation and other technologies for mapping, manipulating and modeling brains, a breakthrough could be imminent. Question: Considering the enormous power that could be unleashed by a solution to the neural code, do we really want it solved?