Brain scans of modern listeners suggest that Aztec whistles sound like human screams, which may have prepared sacrifice victims for their journey to the underworld.

In Aztec culture, the Xoloitzcuintli were often buried with their owners to guide their souls through all nine levels of the underworld, or Mictlán. “Hence the nine songs that ended up being on the ...

They have a symbolic nature related to the dead and the underworld. There is still a lot to uncover about the Aztec death whistle, but it is interesting to see its psychological connection.