The types are probably asymmetric, so Si is connected to Se and Fe/Fi but Se is only connected to Si.

https://en.wikipedia.org/wiki/Two-streams_hypothesis

"The ventral stream is associated with object recognition and form representation. Also described as the 'what' stream, it has strong connections to the medial temporal lobe (which stores long-term memories), the limbic system (which controls emotions), and the dorsal stream (which deals with object locations and motion)."