Using suspenseful music

“Great horror movie music doesn’t often win Oscars, but it does stay with us long after the lights have gone up. There’s an art to using suspense music to create terror, dread, and fear.”  For a scary movie there should be a balance between suspense music and horror music. Suspense music is used to build up tension for the revulsion. The most used instruments to create suspense music are string instruments. Synthesizers are commonly used because of their artificial and eerie sound. Synthesizers are also able to hold notes for longer time, that creates the perfect sounds for a suspense. String instruments have been used to create tension and suspense since the movie Psycho (1960).  
The human brain can be easily fooled. As the heart rate increases the brain “senses” fear. By raising the tempo the heart rate is easily increased and it adds to the fear factor of the movie.