Hi leriel,
The 4th house is ruled by Cancer, so it's related to things like your home, origins... and your instincts, emotional patterns. Perhaps we're close in age b/c I recently experienced trans Saturn opposing Neptune. Rob Hand describes the transit as "disorientation" b/c Saturn and Neptune are so different.
w/my 5 and 11th house activated, I experienced a drop in dream recall, so I was actually *less* disoriented. Life was very concrete. Actually... during that month when the opposition was strongest, I got the crazy idea in my head to not go out (except for school/research) and complete *all* my papers ahead of time, just to see if I had the endurance to do it, which I did, but looking back, that little experiment was really a miserable state of affairs, I'll never never never do it again!!
Of course, since your transit is 4/10th house, this may manifest differently. I see it as a push and pull b/w reality (Saturn) and fantasy (Neptune). Looks like in my case reality won out totally!! Thank god I won't have to see this transit again until I'm like 50!