Sound that makes your hair stand on end

Have you ever had that hair-raising feeling that someone just walked over your grave? You shudder unexpectedly, your hairs stand on end, and you feel suddenly cold or frightened?

Well, English acoustic scientist Dr Richard Lord will tell you that it has nothing to do with your grave, or ghosts for that matter.

Dr Lord and colleagues have discovered that extremely low frequency noises called ‘infrasound’ produce these previously unexplained feelings.

Though you can’t hear this ‘silent music’ the scientists tested their theory by generating infrasound through a seven-metre pipe and asking listeners to report how they were feeling.

22 per cent of listeners reported feelings of increased nervousness, sadness and chills when the infrasound was being generated.

Infrasound also occurs naturally in winds, storms and earthquakes, which might explain why we get that hair-raising feeling even when there’s no seven-metre pipe in sight!

(www.abc.net.au/science/news/health/HealthRepublish_941414.htm)

The Lab, ABC Science online at http://abc.net.au/science/news/