  For over sixty years, it has been reported that microwave electromagnetic
radiation (EMR) had effects on humans which could not be explained by
detectible heating of tissue. Auditory responses to radar, called microwave
hearing, have been the best known of these phenomena. To account for microwave
hearing, many studies in the literature have adopted a rate-of-heating
hypothesis advanced by Foster and Finch in 1974. We show here that theoretical
and experimental studies supporting this hypothesis are weaker than usually
assumed.
  We develop a simple framework of understanding of EMR that may be used to
explain microwave hearing as a nonthermal, nonacoustic effect. We then extend
this approach to other contexts, pointing out several fundamental
misconceptions confounding the field.
  EMR, especially wide-band EMR, primarily must have a nonthermal effect on
living tissue before conversion to heat. Auditory and tactile sensations,
central neurological disability, and blood pressure loss caused by EMR have
been documented. Except microwave hearing, parameters of irradiation causing
such effects have not been explored adequately and remain unknown. There
appears not to be any forensic methodology to prove the cause of harm at
nonthermal levels.
