“…Second, it has been hypothesized that the large‐radius axons of long‐range neurons are essential to maintaining neural synchrony (Buzsáki, Logothetis, & Singer, 2013). However, large‐radii axons come at a disproportionate cost in terms of energy use and spatial constraints (Knowles, 2017; Perge et al, 2009). Histological studies have extensively reported axon radii to be in the range 0.25–1 μm for human brain (Aboitiz et al, 1992; Caminiti, Ghaziri, Galuske, Hof, & Innocenti, 2009; Liewald, Miller, Logothetis, Wagner, & Schüz, 2014; Tang, Nyengaard, Pakkenberg, & Gundersen, 1997), with only 1% of all axons having a radius greater than 1.5 μm (Caminiti et al, 2009).…”