What Triggers the Sensation of Goosebumps in Humans?

Whether you refer to them as goosebumps, chills, or heebie-jeebies, this peculiar yet satisfying sensation occurs when we feel cold, emotionally overwhelmed, or sexually stimulated. These tiny bumps on the skin (resembling a plucked goose) often accompany a shivering feeling along the spine.

Have you ever wondered what causes goosebumps? The explanation is deeply rooted in our primal instincts.

"Goosebumps have ancient evolutionary origins," explains Dr. Keith W. Roach, an internal medicine specialist and Clinical Medicine associate professor at Weill Medical College of Cornell University. He is also the writer of "To Your Good Health," a widely syndicated medical advice column featured in over 150 newspapers.

What Are Goosebumps?

Goosebumps occur due to piloerection, a temporary lifting of the hairs on the skin's surface caused by the contraction of piloerector muscles. These muscles are connected to individual hair follicles and are controlled by the sympathetic nervous system, which also governs the "fight or flight" response. This reaction can be triggered by cold, fear, or surprising events.

Goosebumps serve two functions, though they are largely ineffective for modern humans with less body hair. "One purpose is to provide warmth, which they don't achieve well in humans due to our lack of fur," Roach explains.

For instance, cold weather can induce piloerection in mammals and birds, causing their hair or feathers to stand up and then settle. This process forms an insulating air layer beneath the fur or feathers, helping to protect the animal from cold conditions.

Piloerection also happens when animals sense a nearby threat. In such cases, the contraction of piloerector muscles causes the hair to stand up, creating a 'fluffed up' look that makes the animal appear larger, potentially deterring predators. Picture a Halloween cat. Essentially, piloerection — or goosebumps — has little practical purpose for humans, as we have evolved to have less body hair.

Goosebumps, Music and Our Emotions

Humans can also experience goosebumps during intense emotional moments. "What's fascinating," Roach notes, "is that music and films are among the triggers that can evoke these emotional goosebumps."

Roach references a January 2011 study published in Biological Psychology, where researchers observed subjective chills (akin to spine-tingling shivers) and visible piloerection in volunteers as they listened to music and watched films. The findings were intriguing. Celine Dion's chart-topper "My Heart Will Go On" achieved a 50 percent chill ratio (the "shivers down the spine" effect) and a 14 percent piloerection ratio (goosebumps), while Prince's "Purple Rain" scored a 100 percent chill ratio and a 50 percent piloerection ratio.

How is music connected to goosebumps? Meet Mitchell Colver, a special topics instructor at Utah State University. With a background in music and psychology, Colver conducted a groundbreaking study during his graduate studies at Eastern Washington University in 2010, exploring which individuals are most prone to experiencing goosebumps. (Refer to the sidebar for details.) Published in the March 2015 issue of Psychology of Music, the study gained widespread attention and established Colver as a leading expert on the subject.

"To fully grasp goosebumps, you need to recognize that you have two brains — the emotional brain and the thinking brain — and they react differently to external stimuli," he explains.

The emotional brain is instinctive. Like a rabbit in the wild, it constantly scans for threats and, upon detecting one, initiates an automatic physiological reaction known as the fight-or-flight response. This survival mechanism causes the emotional brain to act swiftly, often bypassing the thinking brain.

Regarding surprises, Colver cites David Huron, author of Sweet Anticipation: Music and the Psychology of Expectation: "To your emotional brain, there’s no such thing as a pleasant surprise."

"When environmental sounds, including musical tones, are detected, the emotional brain doesn't interpret them as music. Instead, it perceives a scream or a high-pitched violin note at a certain frequency as a potential threat," Colver explains.

In music, unexpected harmonies or abrupt shifts in volume can induce chills by 'violating' the listener's expectations, creating a sense that something is amiss.

Moments later, the thinking brain intervenes, reassessing the situation. It identifies the high notes as music, deems them harmless, and quiets the emotional brain, causing the goosebumps to disappear. This 'violation of expectations' creates what Colver calls 'aesthetic tension' — a buildup of tension from the emotional brain's reaction to a perceived threat, followed by relief when the thinking brain recognizes the stimuli as enjoyable and signals safety.

Is it Fear or is it Pleasure?

Recall the rabbit in the forest? In nature, once a threat disappears, the rabbit resumes grazing. "But when humans reinterpret something as aesthetic beauty [instead of a real threat], we experience a dopamine surge," Colver explains. Dopamine is the body's "feel-good" hormone. "That's why goosebumps feel pleasurable to humans."

The experience of pleasurable goosebumps while listening to music is known as frisson, a French term meaning "aesthetic chill." Some experts refer to it as a "skin orgasm," a description Colver finds fitting.

"Dopamine floods the same brain region activated during orgasm. So, calling it a skin orgasm is scientifically accurate. An orgasm is essentially a release after intense tension," he says. "Many people don't realize that the joy lies in the release of tension. Great music builds and resolves psychological tension in a similar way."

What about goosebumps caused by touch, such as tickling or during intimacy? Are these reactions rooted in fear? Colver believes they are.

"Keep in mind, there’s no such thing as a pleasant surprise," he states. Goosebumps triggered by touch or tickling often affect areas of the body that are typically covered or guarded, creating a sense of vulnerability and prompting an instant reaction from the emotional brain. This is subsequently followed by the thinking brain's reevaluation and, if fortunate, a rewarding surge of dopamine.