Oct. 12, 2012 -- The sound of nails on a chalkboard or screams may send shivers down the spine for a good reason. A new study shows annoying sounds trigger a highly emotional response in the brain.

While many of us may find the sounds of chewing or breathing off-putting, for some they're unbearable -- and new research has shown their brains are going into overdrive. While many of us may find the ...