One of the earlier investigations came from Steyn-Ross et al. [12], who extended a generalized mean field firing-rate model that postulates specific short range and long range connections between cortical neurons.
Our experience simulating spatially structured neural mass models, together with considerations of the anatomy of the brain, suggests that such a regime could require the addition of long range connections.
The model demonstrates that the precise spatiotemporal spread of activity seen in the cortical slice results from long range connections that target specific orientation domains whilst distinct regions of suppressed activity are shown to arise from local isotropic axonal projections.
Meanwhile, long range connections in advanced cortex were found to be more plastic, and these connections were prone to the exterior influences [7].
For example, a network with N = 100, k = 10 and p = 0.1 containing 900 local connections and 100 long range connections, removing 200 edges will on average affect 180 local connections and twenty long range connections, resulting in a network with N = 100, k = 8 and p = 0.1.
However, it is believed that the high cut-off value used would likely have produced fewer false positives in the long range connections and fibre pathways identified.
This led to the postulation of the underconnectivity theory, which postulates that fewer long range connections between different regions are present, leading to decreased synchronization between regions of the brain and decreased global information processing (Casanova et al, 2006).
As expected for parallel growth, group 1 versus group 2 did not display significantly higher degree, long-range connection lengths or bidirectional connectivity differences.
SWR stands for the small world ring with one random long-range connection.
