[pygy_]

Those are two different kinds of connectivity.

The first is about synapse density, the second about how strongly different parts of the brain are linked together (relative to one another).

So a brain with a low average synapse density may still have some areas more functionally connected than the average population.

The default mode network and the attention-related fronto-parietal networks are usually disconnected functionally, they inhibit one another.

See https://en.wikipedia.org/wiki/Dynamic_functional_connectivit... for details