Maybe you’re pressed up against a date, watching The National’s relentless breakdown in “Afraid of Everyone.” Maybe you’re alone in your bedroom listening to James Blake suffer from “A Case of You.” Maybe you’re baking in the summer heat as Phish meanders through a sprawling version of “The Lizards.” It happens quickly: a crescendo runs beneath your skin, and you feel the prickle of rising goosebumps. You feel otherwise normal, but you suspect that maybe something is happening.

Time to confirm that suspicion: On an emotional level, a whole hell of a lot is happening.

At the center of the Venn diagram of emotions triggered by experiences — bear attacks, sex, and live Bonnie Raitt sets — is a simple physiological/emotional phenomenon: stress. All of these things kick the brain into emotional overdrive to varying degrees, triggering the release of neurotransmitters like adrenaline and dopamine, which jolt the brain and prick the skin.

Evolutionarily speaking, it makes sense that goosebumps are the body’s immediate response to stress. It’s been suggested that hairy animals, stressed out by the cold, evolved the goosebump reflex to stay warm; the release of adrenaline causes the tiny muscles around each hair to contract, pulling the skin taut and forcing each hair to stand on end, making room for more warmth-trapping air to draw near and insulate the body. Goosebumps also tend to spread in response to physical threat; anyone who’s ever seen an angry cat’s fur stand on end has witnessed evolution’s adrenaline-driven mechanism for making the animal seem bigger than it is.

For the most part, we’re no longer furry animals that face predators and extreme cold, but Homo sapiens in 2016 have their own, admittedly low-key, stressors to deal with. If you think of songs as direct attacks on our emotions, we’re going into battle every time we switch on Spotify. The right song — that is, the kind that triggers the swell of emotion — is going to trigger the brain’s release of the aforementioned adrenaline and the flush of goosebumps.

Some attacks are inherently more direct than others. Breaking down Adele’s “Someone Like You” and Adele’s “Hello,” — really, any song by Adele — has shown that her vocal style is especially good at eliciting tension. As the Wall Street Journal pointed out, her singing contains an appoggiatura, an often dissonant ornamental note that “leans” into the main note in the melody to elicit those feels; it’s that slight tonal dip — she often does this repeatedly — as she sings the drawn-out “you” on the chorus to “Someone Like You” that creates the feeling of tension and resolution that triggers a stress response followed by a feeling of catharsis.

University of British Columbia psychologist Martin Guhn attempted to break down the elements of the musical “chill response” in a 2007 study. Songs that featured big, unexpected jumps in dynamics — from loud to soft, or vice versa — gave people goosebumps; so did songs that incorporated surprising harmonies, jumps in frequency, and unexpected changes in melody. More than anything, it’s drama that elicits emotional — and physiological — responses. The anticipation of resolution can sometimes be as rewarding as the resolution itself (more on that later).

Disturbed’s cover of Simon and Garfunkel’s “Sound of Silence,” with its abrupt harmonies, orchestral swell, and sudden dip in volume, falls into this category (it could be argued that this cover is more dramatic than the original); the unexpected harmonies between soft vocals and sensual strings on Rhye’s “Open” — a very different song — have the same dramatic effect. Vocals don’t even have to be part of the equation: The accelerating polyphony of twanging guitar solos, layered with the buildup of drums on the breakdown of Women’s “Shaking Hand,” is, arguably, just as emotionally intense as Jason Molina’s racing time signature on “Farewell Transmission.”

Of course, the meaning behind a song and the memories we associate with them are just as powerful at triggering goosebumps as the song’s musical structure itself. If, like thousands of teens that came of age in 2004, you can’t psychologically separate Jeff Buckley’s “Hallelujah” from Ryan Atwood’s heartbreaking drive away from The O.C., of course the song is going to give you the chills. The phenomenon is ultimately subjective.

What’s universal is the fact that we all crave that prickle of goosebumps, even if it does, in a physiological sense, herald the onset of emotional stress. The rush of adrenaline — responsible, in some instances, for your tears, sweaty palms, racing pulse, and, yes, goosebumps — is often accompanied by the release of dopamine, a neurotransmitter involved in the reward system. One paper in Nature, noting music’s ability to “arouse feelings of euphoria and craving,” suggested that during certain songs, we hit “peak emotional arousal” — which is when the brain releases dopamine. (Incidentally, the brain does pretty much the same thing after we do drugs, gamble, and go sky-diving.) Even the anticipation of that reward releases dopamine through a completely separate mechanism. It feels good to hit that peak, and it also feels good to want to hit that peak.

The ability to induce goosebumps doesn’t necessarily make a song good, but it does makes it meaningful — whether you’re conscious of it or not. This can be a useful tool for music appreciation. You might not, on a cognitive level, assume or want to admit that, say, Ariana Grande’s a cappella version of “Dangerous Woman” could elicit a real emotional response; but if the echo of her smoky soprano triggers a flush of shivers against your will, then your brain is feeling all the feels, whether you want it to or not.

Your body knows you better than you do.