A thrilling conjecture proposes that the brain might operate close to the critical point of a phase transition, with avalanches of activity obeying power-law distributions, which might entail a number of precious functional advantages. We scrutinize one of the most accepted computational models for neural activity, confirming the emergence of generic scale-free avalanches. However, we elucidate that it has nothing to do with self-organization to the critical point of a continuous phase transition; instead, it stems from the fact that perturbations to the system exhibit a neutral drift, similar to the one in neutral theories of population genetics and ecology. We study the origin, relevance, and consequences of such a neutral neural dynamics.
