Abigail Lim
Science & Tech Editor
Reactions to and enjoyment of scary movies tend to be highly polarizing. While many claim to love the feeling of hairs standing up on their necks, goosebumps rising on their skin, and hearts pounding against their chests, others try to avoid these feelings altogether. Yet even reducing the horror genre down to these physical responses is a major oversimplification of what it means for a movie to be “scary.”
Our physiological responses to stress vary from person to person. Even though common reactions to scary movies include increased cardiovascular function, pupil dilation, and quickened breathing, many don’t respond at all to certain kinds of horror or only respond to certain subgenres. After all, the intent of slasher films differs significantly from the purpose of gothic fiction. While we typically think of scary movies as being filled with suspense, jump scares, and the unbelievable, a common theme among the horror categories utilizes human intrinsic fears.
The endocrine system coordinates the release and production of hormones into the bloodstream. Hormones are chemicals that regulate bodily functions like metabolism, reproduction, and growth. The hypothalamic-pituitary-adrenal (HPA) axis is the system of endocrine organs that elicits a stress response in the body when humans react to a stimulus, which is commonly known as fight-or-flight. In a series of activating steps, the hypothalamus located in the brain begins the chain by delivering corticotropin-releasing factor (CRF), a hormone, into the bloodstream. The anterior pituitary gland situated below the hypothalamus then reacts to CRF by releasing adrenocorticotropic hormone (ACTH), which travels to the adrenal glands located on top of the kidneys. Here, ACTH causes the glands to release cortisol, which binds to glucocorticoid receptors throughout the body that then release epinephrine, also known as adrenaline. Cortisol, the “stress chemical,” then enters the bloodstream and induces a variety of physiological changes in the body, such as suppressing inflammation, regulating blood pressure, and providing energy for response. Both cortisol and adrenaline work in conjunction to elicit these physiological and behavioral changes.
Essentially, scary movies provide the stimulus that initiates this sequence of events within the body’s fear response system and leads to a physical response. As a regulator of the human stress response, the HPA axis was and continues to prove essential to our adaptation and survival. But if this mechanism was intended to keep us safe, why is it that many of us enjoy, and even seek out, forms of entertainment that make us scared?
While nature and nurture are not opposing concepts (as often suggested in middle and high school), some fears seem to be naturally encoded in us from birth. This indicates that there is a long-term evolutionary purpose for certain fears, such as loud noises, falling, and spiders. However, other fears may not be common to everyone, and propensity to be scared of these stimuli can be influenced through learned experience. Some even suggest that controlled fear in a safe environment may be beneficial for organisms who want to safely understand the dangers around them. Similar sensations are elicited by thrill-seeking activities like skydiving, riding roller coasters, and rock climbing. Even the major sense of relief or post-viewing understanding that we are rooted in the comfort of our reality may provide people a sensation they continue craving.
Additionally, horror movies may help people exert a sense of control over their daily anxieties by giving them a choice over the source of fear. While many fans feel enthralled by their movie-watching experience, the power over how much they watch and what they watch still lies with the viewer. In a world of doom scrolling and arguably unhealthy online behaviors, watching scary movies can also train the brain to focus its attention on the storyline and away from everyday worries.
Although the body’s stress reaction is evolutionarily essential and can be used in fun, safe ways to bring us enjoyment, prolonged stress can also lead to negative health consequences. The very same short-term physical responses that horror movies induce may culminate in chronic stress effects. Since stress hormones are widely expressed in immune cells, the endocrine and immune systems are inextricably linked. Experiencing stress that extends beyond momentary responses can increase inflammation, cardiovascular dysfunction, autoimmune syndromes, and mental disorders. Though it’s not to say that avid horror film fans will inevitably develop these ailments, it is important for all people who are exposed to regular, acute stress to be mindful of their behaviors and attitudes. Self-care, mindfulness, and checking in with your mind-body connection is crucial to managing and mitigating chronic stress.
The realm of horror offers innumerable movie options in terms of style, content, and degree of fright. While psychological horror’s puzzling twists and turns might leave your mind feeling bent and exhausted, body horror’s gruesome imagery might leave you feeling physically ill. Choosing the ideal scary movie ultimately depends on the viewer’s preferences, and understanding physiological reactions to fear can help influence one’s decision.