by Medical Xpress
The brain shares a similar pattern of connections with other complex networks such as social networks and the world wide web. However, until now, it was not known what rules were involved in the formation of the human brain network.
The scientists, from the Behavioral and Clinical Neuroscience Institute in the Department of Psychiatry, and the National Institute of Mental Health in the US, discovered that the network can be modeled as a result of just two different competing factors: a distance penalty based on the cost of maintaining long-range connections between various brain regions and a second term modeling the preference for links between regions sharing similar input.
Professor Ed Bullmore, lead author on the paper, explains the dynamic between the parameters they identified: “There is a huge amount of evidence that the wiring of brain networks tends to minimize connection costs. Less costly, short-distance connections are much more numerous than more costly, long-distance connections. So our modelrealistically includes a distance penalty on long-distance connections, which will tend to keep connection costs low.
“However, we found that cost control alone was not enough to reproduce a wide range of network properties. To do that, we had to model an economical trade-off between cost control and another term which favoured new, direct connections between regions that shared similar input or were otherwise already indirectly linked.”