Sonic Weapon - Research

Research

See also: United States Department of Defense policy on non-lethal weapons

Some common bio-effects of electromagnetic or other non-lethal weapons include effects to the human central nervous system resulting in physical pain, breathing difficulty, vertigo, nausea, disorientation, or other systemic discomfort. Interference with breathing poses the most significant and potentially lethal results. Light and repetitive visual signals can induce epileptic seizures (see Bucha effect). Vection and motion sickness can also occur. Cavitation, which affects gas nuclei in human tissue, and heating can result from exposure to ultrasound and can cause damage to tissue and organs.

Studies have found that exposure to high intensity ultrasound at frequencies from 700 kHz to 3.6 MHz can cause lung and intestinal damage in mice. Heart rate patterns following vibroacoustic stimulation has resulted in serious negative consequences such as atrial flutter and bradycardia.

The extra-aural (unrelated to hearing) bioeffects on various internal organs and the central nervous system included auditory shifts, vibrotactile sensitivity change, muscle contraction, cardiovascular function change, central nervous system effects, vestibular (inner ear) effects, and chest wall/lung tissue effects. Researchers found that low frequency sonar exposure could result in significant cavitations, hypothermia, and tissue shearing. No follow on experiments were recommended. Tests performed on mice show the threshold for both lung and liver damage occurs at about 184 dB. Damage increases rapidly as intensity is increased.

Noise-induced neurologic disturbances in humans exposed to continuous low frequency tones for durations longer than 15 minutes has involved in some cases the development of immediate and long term problems affecting brain tissue. The symptoms resembled those of individuals who had suffered minor head injuries. One theory for a causal mechanism is that the prolonged sound exposure resulted in enough mechanical strain to brain tissue to induce an encephalopathy.