In 2011, the authors estimated that every 7.4 years, the number of neurons we can record with doubles. Think of it as Moore’s law for brain recordings. Since then, Stevenson has updated the estimate, which now stands at 6 years. Could it be that progress itself is accelerating?
…We can do one better—fit a double-exponential model. This is only a few lines of code in PyMC3—a miracle of automatic differentiation and Hamiltonian Monte Carlo. Here’s what that looks like:
You can see visually this is a much better fit, and it implies something pretty dramatic: progress itself is accelerating. That means that doubling time itself has changed over time—and it currently stands at 3.6 years under this model [95% CI 3.5–3.7]…These results project a 1M neuron average recording capability by 2045—of course, this discounts ceiling effects and potential paradigm shifts, which could adjust these bounds far upward or downward.