Brain processes develop through sequences of heterogeneous bursts of neural activity. This behavior is reminiscent of fluctuation phenomena in crystal plasticity, where strain avalanches mediate the deformation of crystalline materials at microscopic length scales. In analogy with crystal plasticity, neural avalanche sizes are distributed as power laws, whose origin is currently not understood. I will present recent results on the emergence of such phenomena in the brain, emphasizing the role played by the hierarchical topology of brain networks. I will stress the analogies with the case of strain avalanches and show how, at macroscopic scales, concepts of amorphous plasticity can be borrowed to explain electroencephalography patterns.
