Discussion: The blood‐brain barrier, cerebral circulation, and mathematical modeling

There is little doubt that intense biological stress, whether thermal, mechanical, or chemical in origin, can increase the permeability of the blood‐brain barrier. There is increasing doubt that microwave fields that result in trivial elevations of brain temperature are affecting the tight junctions of the barrier. One cannot discount the data—Allan Frey and Kenneth Oscar and their respective colleagues did observe some kind of neurocirculatory response in their studies—but it appears now that altered cerebral circulation, not a loosening of junctions, was responsible for their findings. While one cannot dismiss the possibility of augmented transport (passive or active) that is unrelated to the mechanics of the tight junction, one can argue that suitable biological assays will have to be deployed before final answers are achieved.