BEHAVIORAL BIOPHYSICS

A computational investigation of strain concentration in the brain in response to a rapid temperature rise

Following the mysterious health attacks on U.S. diplomats in Cuba in 2016, the cause of concussion-like symptoms concurrent with strange noises heard by the diplomats remains undetermined. A wide range of possible causes of the sensations have been proposed: pulsed microwave exposure, infrasound acoustic devices, pesticides/neurotoxins, and even mass hysteria (psychogenic illness). Here, we numerically examine the pulsed microwave exposure hypothesis and the simulated mechanical response of brain tissue. A computational model is used to examine the influence of various spatially varying temperature gradients and pulse durations on the mechanical response of brain tissue. We show that a stress-focusing effect due to a rapid temperature increase may result in brain tissue strains larger than the initially applied thermal strains.

Radiofrequency (RF) sickness in the Lilienfeld Study: an effect of modulated microwaves?

There is a controversy among professionals regarding whether radiofrequency radiation sickness syndrome is a medical entity. In this study, this controversy was evaluated with a methodology adapted from case studies. The author reviewed U.S. literature, which revealed that research results are sufficiently consistent to warrant further inquiry. A review of statistically significant health effects noted in the Lilienfeld Study provided evidence that the disregarded health conditions match the cluster attributed to the radiofrequency sickness syndrome, thus establishing a possible correlation between health effects and chronic exposure to low-intensity, modulated microwave radiation. The author discusses these health effects relative to (a) exposure parameters recorded at the U.S. Embassy in Moscow and (b) the Soviet 10-microwatt safety standard for the public. Given the evidence, new research-with current knowledge and technology-is proposed.

Psychological studies in nonionizing electromagnetic energy research

Research on nonionizing electromagnetic (NIEM) energy has focused on potential hazards, and to a lesser degree beneficial applications, of radiofrequency (RF) fields and extremely low frequency (ELF) fields. The history of research on the potential biological effects of NIEM contains many psychological investigations. These psychological investigations were conducted primarily in the discipline of biopsychology and included interdisciplinary cooperation with engineering, physical sciences, and other disciplines not routinely associated with psychology. The current recommended exposure level for RF is based on behavioral observations of laboratory animals. Psychology has been and continues to be in the midst of controversy regarding the ability of low-frequency, low-level electromagnetic energy or electric and magnetic fields to affect living organisms.

Electrical states in the rabbit brain can be altered by light and electromagnetic fields

The effect of low-frequency magnetic fields on the rabbit electroencephalograph (EEG) was studied using a quantitative procedure that permitted statistical evaluation of the response of individual animals. The field conditions used were those predicted by various theories to result in field-animal interactions; light and sham exposure were employed as positive and negative controls, respectively. Sixty-seven percent of the rabbits exhibited changes in the EEG power spectra when light was presented in 2-s epochs; none of the animals responded to sham exposure. When 1 Gauss, 5 Hz, was presented in 2-s epochs, 100% of the animals tested responded to the presence of the field. The rabbits did not respond when the magnetic-field frequency was higher than the physiological range (1-20 Hz) or when it was tuned for resonance of K+. The results showed that an electrical state function may be operationally defined for the rabbit brain, and used to assess the occurrence of an interaction between an animal and external magnetic fields.

Human perception of illumination with pulsed ultrahigh-frequency electromagnetic energy

A psychophysical study of the perception of "sound" induced by illumination with pulse-modulated, ultrahigh-frequency electromagnetic energy indicated that perception was primarily dependent upon peak power and secondarily dependent upon pulse width. The average power did not significantly affect perception. Perceived characteristics of pitch and timbre appeared to be functions of modulation.

Behavioral sensitivity to microwave irradiation

Rats assayed by the technique of conditional suppression were able to detect the presence of 12.25-centimeter microwaves at doses of power approximating 0.5 to 6.4 milliwatts per gram. The assay, which controlled for sensitization, for pseudo and temporal conditioning, and for several possible sources of artifactual cueing, revealed that irradiation by microwaves, although lacking the saliency of an auditory stimulus, can function as a highly reliable cue. Efficiency of detection was strongly and positively related to the amount of microwave energy to which the rats were exposed.

Electromagnetic emission at micron wavelengths from active nerves

In recent years there has been experimental work and speculation bearing upon the significance in neural functioning of electromagnetic energy in the region of the spectrum between 0.3 and 10 mu. We demonstrate, in this experiment, micron wavelength electromagnetic emission from active live crab nerves as compared to inactive live and dead nerves. Further, the data indicate that the active nerve emission is caused by specific biophysical reactions rather than being simply black-body radiation.

A Case of Dermooptical Perception

A 21-yr.-old woman was found to possess the ability to discriminate colors through her fingertips under conditions which controlled for normal visual information, order of stimulus presentation, experimenter-produced cues, and textural differences. A forced-choice method employing four different colors and knowledge of results was used. The data indicated that light on the stimulus cards was necessary for her discrimination.