There is no doubt that cognition and intelligence are the result of neural activity --- but how? How do molecules, neurons and synapses give rise to reasoning, language, plans, stories, art, math? Despite dazzling progress in experimental neuroscience, as well as in cognitive science, we do not seem to be making progress in the overarching question. The reason is that these two communities are separated by a huge gap --- not just in scale, but also in experimental methodology and mindset. As Richard Axel recently put it in an interview to Neuron: "We don't have a logic for the transformation of neural activity into thought [...]."
What kind of formal system would qualify as this "logic"?
I will introduce the Assembly Calculus, a computational system whose basic data structure is the assembly: assemblies are large populations of neurons representing concepts, words, ideas, episodes, etc.The Assembly Calculus is biologically plausible in the following two orthogonal senses: Its primitives are properties of assemblies observed in experiments, or useful for explaining other experiments, and can be provably (through both mathematical proof and simulations in biologically realistic platforms) "compiled down" to the activity of neurons and synapses. Furthermore, The Assembly Calculus can be shown both mathematically and experimentally to simulate simple high-level cognitive functions, such as parsing simple sentences, as well as planning. We believe that this formalism is well positioned to help in bridging the gap between the brain and the mind.