The human brain is organized into a collection of interacting networks with specialized functions to support various cognitive functions. At the micro level, the brain elements consist of single neurons, the amount of which often treads the realm of hundreds of billions, and possible connections between them numbering in the order of 10¹⁵. At a more macro level, the brain is parcellated into a number of regions, where each region accounts for the activity and coactivity of a population of neurons.