Lack of Effects on Goal-Directed Behavior of High-Intensity Infrasound in a Resonant Reverberant Chamber.

摘要

It has been hypothesized that high-intensity low-frequency sound (20- 100 Hz) and infrasound (below 20 Hz) could incapacitate personnel located within buildings or underground facilities. A unique reverberant resonant chamber was designed and constructed of reinforced concrete, and incorporated a moveable wall to allow tuning to specific frequencies. Two minipigs (Sus scrofa) were trained to press a panel for food delivery. The tuning wall was positioned to create standing waves of maximal intensity at frequencies of 10, 12, 15, and 20 Hz. Four subwoofer speakers were used to produce sinusoidal signals at the tuned frequency of the chamber and at 2 and 4 times the tuned frequency. Over numerous trials, there was only a minimal impact on consummatory and escape behavior that rapidly dissipated with repeated exposures. In another series, 2 rhesus monkeys (Macaca mulatta) were trained on a continuous, compensatory- tracking task. The tuning wall was set for 10 Hz, with signals at 10 and 20 Hz. Subject behavior was not substantially affected. It seems unlikely that high- intensity acoustic energy (20-80 Hz, up to 145 dB) can be used to facilitate hostage rescue. Due to the difficulty of obtaining high sound pressure levels in a large volume, further extensive experimentation is not suggested.