With a gross earning of $8billion worldwide just from 1995 onward, the genre that provides a venue for controlled fear shares an attraction with extreme sports and activities.

Any sense of aversion toward the gore and bloody flesh wreaking mayhem onscreen is overcome by the combination of adrenaline boost and the subconscious knowledge of relative safety.

In fear, the amygdala initiates physiological responses to the stimulus and facilitates the release of dopamine and adrenaline. Pupil dilation and palm sweat, characteristic of fight or flight response, are accompanied by this chemical rush.

Dr Bryan Roche of Maynooth University in Ireland explains this phenomenon.  "Fear and pleasure are very closely related. The same physiological reactions occur in both cases, and in fact using a polygraoh machine to measure heart rate, pupillary dilation, electrical skin conductance, breathing rate, and other physiological activities will not really tell you whether a persons is afraid or excited."

Where some would say that watching a horror film is fun and is a thrill, others may interpret the same experience as a negative and terrifying experience.

Based on his study, psychology professor Dr David Zald of Vanderbilt University relays that some individuals do not have what he calls brakes whenever dopamine is released. These individuals generally display more attraction to the sense of fear.

Dr. Margee Kerr explains the attraction further in saying that these cultured environments of fear also provide humans with a sense of unity, belonging and, to a certain degree, power.  This is why humans chase thrills such as bungee jumping, sky diving and rollercoaster rides.  Rollercoasters were inspired by 17th century Russian high-speed ice slides.

London Horror Society founder Chris Nials, whose first horror film experience was John Carpenter's Halloween, shares, "For me, I get the biggest kick out of watching a film that affects me emotionally and is loaded with twists and surprises. I like to leave the cinema or sofa still thinking about what I've just seen for hours on end!"