Study: Infrasound likely a key factor in alleged hauntings

Testing the body’s stress response A chance conversation with neuroscientist colleague (and co-author) Kale Scatterty inspired this latest study. Scatterty co-authored a 2023 paper demonstrating an aversion in zebrafish to infrasound, specifically an anxiety response that caused the fish to avoid certain tank areas. This suggested a physiological response to infrasound, and Schmaltz wanted to see if this was also true in humans. So they designed a lab-based experiment to test the hypothesis that cortisol levels in people’s saliva—part of the body’s normal stress response—would increase in response to infrasound. Visual layout of the testing area and equipment used in producing infrasound. Credit: K.R. Scatterty et al., 2026 Visual layout of the testing area and equipment used in producing infrasound. Credit: K.R. Scatterty et al., 2026 Thirty-six participants sat alone in a room and were exposed either to calming music similar to what one might hear in a yoga setting, or “more unsettling ambient music,” per Schmaltz, with half of them also being exposed to infrasound emitted from hidden subwoofers. “What we thought might happen was when the infrasound was on, people would find the calming music even more relaxing, while the scarier music would be scarier,” he said. …