From the article

“Low-frequency infrasound waves bypass standard sensory receptors to vibrate cochlear support cells, proving that these structural units generate local alternative electric fields that trigger unique, non-linear nerve pathways straight to the human brain.”

Summary: Researchers have demonstrated that the human brain processes low-frequency infrasound using an entirely unique biological mechanism. When acoustic waves drop too low for standard auditory hair cells to register, the energy bypasses them completely, hijacking the inner ear’s structural support cells instead. These support units generate alternative electric fields that fire off unique nerve pathways, explaining why infrasound registers more as a raw physical sensation or internal hum than a standard audible sound.

The Non-Linear Volume Spike: This unique biological pathway explains a well-known acoustic puzzle: when infrasound levels creep up even slightly, the perceived volume escalates at an incredibly rapid, non-linear rate. Small steps in environmental pressure instantly make the sound feel overwhelmingly louder.

“Humans can actually perceive infrasound if the sound level is high enough,” says Carlos Jurado, postdoctoral fellow at the Department of Neuromedicine and Movement Science at the Norwegian University of Science and Technology (NTNU).

Some are more sensitive to low-frequency noise. For example, it can come from ventilation systems, heat pumps, wind turbines, industry, transport, generators or transformers. But this is difficult to measure, because the sound is often perceived more as a hum or physical sensation than more high-frequency sound does.

A new study proves low-frequency infrasound hijacks inner ear support cells to create unique physical hum sensations.