I too had an experience of the 'whoosh' but it was much later after the initial bonk on the head I had. My syncope (post marathon) was in June '09, all PCS symptoms were completely gone by September '09. In Dec '09 I had colon surgery and was on the mend. While on a trip out of town in Jan '10, my family and I were sitting for lunch in a cafe, and I was hit by the 'whoosh', dizziness, warm sensation, an almost syncope feeling, kind of a panic feeling. Then all of the PCS symptoms came back first with a raging headache, dizziness, fog, etc. Symptoms are a little better now than they were in Feb, but it's strange that this second round wasn't aggrivated by an actual blow to the head.

Mike