A unified picture of neuronal avalanches arises from the understanding of sampling effects
Published in biorxiv, 2019
Recommended citation: Neto, J. P., Spitzner, F. P. & Priesemann, V. A unified picture of neuronal avalanches arises from the understanding of sampling effects. (2019). doi:10.1101/759613 https://www.biorxiv.org/content/10.1101/759613v1
Abstract:
To date, it is still impossible to sample the entire mammalian brain with single-neuron precision. This forces one to either use spikes (focusing on few neurons) or to use coarse-sampled activity (averaging over many neurons, e.g. ~LFP). Naturally, the sampling technique impacts inference about collective properties. Here, we emulate both sampling techniques on a spiking model to quantify how they alter observed correlations and signatures of criticality. We discover a general effect: when the inter-electrode distance is small, electrodes sample overlapping regions in space, which increases the correlation between the signals. For coarse-sampled activity, this can produce power-law distributions even for non-critical systems. In contrast, spikes enable one to distinguish the underlying dynamics. This explains why coarse measures and spikes have produced contradicting results in the past – that are now all consistent with a slightly subcritical regime.