"In neuroscience, the default mode network is a network of brain regions that are active when the individual is not focused on the outside world and the brain is at wakeful rest. Also called the default network, default state network, or task-negative network (TNN), it is characterized by coherent neuronal oscillations at a rate lower than 0.1 Hz (one every ten seconds). During goal-oriented activity, the DMN is deactivated and another network, the task-positive network (TPN) is activated. The default network may correspond to task-independent introspection, or self-referential thought, while the TPN corresponds to action, and that perhaps the TNN and TPN may be "considered elements of a single default network with anti-correlated components"."
"The task-positive network (TPN), also known as the dorsal attention network (DAN), is one of two sensory orienting systems in the human brain, the other being the task-negative network. It is involved in voluntary (top-down) orienting and shows activity increases after presentation of cues indicating where, when, or to what subjects should direct their attention."
In the Neojungian Typology, Processing-task will be related to activity in the dorsal attention network (DAN) and Execution-task will be related to activity in the dorsal attention network (DAN) and default-mode network balanced by the frontoparietal control network. Activity in the default-mode network (DMN) is probably related to the introversion feature described in Jungian psychology.
The frontoparietal control network can communicate with the DAN, DMN and both simulatenously. It is possible that when Executors enter their default-mode network they also activate their frontoparietal control network and the daydreaming will be goal-oriented. I also believe in the theory that the default-mode network is also doing a kind of subconscious memory-consolidation.
"Two functionally distinct, and potentially competing, brain networks have been recently identified that can be broadly distinguished by their contrasting roles in attention to the external world versus internally directed mentation involving long-term memory. At the core of these two networks are the dorsal attention system and the hippocampal-cortical memory system, a component of the brain's default network. Here spontaneous blood-oxygenation-level-dependent (BOLD) signal correlations were used in three separate functional magnetic resonance imaging data sets (n = 105) to define a third system, the frontoparietal control system, which is spatially interposed between these two previously defined systems."