Three days after Jenna Tocatlian saw Taylor Swift perform at Gillette Stadium in Massachusetts, she was still on cloud nine. But something felt weird when she tried to relive the memories: in her mind, where vivid specifics of the concert should have been playing on loop, there was just a blank space.
“Post-concert amnesia is real,” says Tocatlian, 25, who lives in New York. She got to hear her top choice for one of Swift’s nightly “surprise songs”—Better Man—and the experience still feels surreal. “If I didn’t have the 5-minute video that my friend kindly took of me jamming to it, I probably would have told everyone that it didn’t happen,” she says. During the hour-long wait to exit the stadium, she started re-listening to the setlist, asking her friends: “Did she really play that? How much of it did she play?” Tocatlian chalks it up to sensory overload—and the fact that she had been dreaming about the big night for so long, it was difficult to grasp it was really happening. “It’s hard to put together what you actually witness,” she says. “You’re having all these emotions while your favorite songs are playing, and you’re like, ‘Wow, where am I?’”
Every weekend, from March until August, hundreds of thousands of people are packing stadiums across the U.S. to watch Swift’s hugely popular, three-hour Eras Tour. Many later take to social-media platforms like Reddit to describe their inability to recall small details or even large parts of the show. One person wrote that they had waited six months for the concert—and after it ended, their brain tried to convince them they hadn’t been there. Another wondered if they had dissociated during it, and described feeling guilty about not leaving with more vivid memories.
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That resonates with Nicole Booz, 32, of Gettysburg, Pa., who attended Swift’s May 14 show in Philadelphia. Looking back, it feels like “an out-of-body experience, as though it didn’t really happen to me,” she says. “Yet I know it did, because my bank account took a $950 hit to cover the ticket.”
So what’s going on? For starters, people might simply be too excited, explains Ewan McNay, an associate professor in the department of psychology at the State University of New York at Albany. “This is not a concert-specific phenomenon—it can happen any time you’re in a highly emotional state,” he says. People getting married, for example, often say they can’t remember their first dance, or if their Aunt Josephine was there. As the body’s stress levels increase—in response to exciting or distressing factors—the neurons associated with memory start firing indiscriminately. That makes it “really hard” to form new memories. “If you’re slightly on edge, with a little bit of excitement, you’ll actually remember better,” McNay says. “But too much excitement pushes you over the edge in terms of memory formation, and you’re unable to make memories.”
There’s a scientific, biological explanation for exactly what happens when you get this excited (which the body sees as a state of stress). It starts pumping out glucose—the brain’s favorite molecule for fueling memory, thinking, and learning—from your liver into your bloodstream. Imagine you ran into a bear in the woods, for example: “You want that fuel for your muscles to go and fight the bear or run away from the bear,” McNay says, not wasted on something like memory formation. At the same time, your vagal nerves—which regulate internal organ functions—become stimulated. “You’re saying, ‘Hey, we’re really stressed out: we’re running away from the bear, or we’re watching Taylor Swift.’”
This response causes your amygdala—the part of the brain responsible for emotional processing—to release a neurotransmitter called norepinephrine. It helps tag memories as having high emotional content, enhancing the likelihood that they’ll be saved vividly in your mind. But McNay describes the process as an inverted U: A little bit is good; too much is bad, he says. Plus, if you add caffeine or alcohol to the mix, you’ll likely push the curve even further to the right, which means your brain will have a tougher time creating and saving new memories.
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It can be surprising and disappointing not to remember everything you think you should about a big event, says Robert Kraft, a professor of cognitive psychology at Otterbein University in Westerville, Ohio. “We paid a lot of money, we’re looking forward to it, and afterwards, we want to luxuriate in our memories of the concert,” he says. “But our expectations are too high. That’s not what memory is—it’s not a recorder.”
One of the core misconceptions many people have about memory, he says, is that they think of forgetting as a deficiency. In reality, we’re simply not designed to remember everything. Situations in which we explicitly focus on remembering are typically limited to stuff like studying for an exam or memorizing a presentation. “We don’t set out to remember our lives—we set out to experience them,” Kraft says. “Not remembering is actually a tribute to being in the moment and enjoying it.”
Still, if you’re adamant that you want to better remember an important event, a few strategies can help. The first is a purely mental approach, McNay says: You can try to achieve a “semi-meditative state,” perhaps by telling yourself to chill out and be present. Or, consider a more physical approach. Your brain monitors your body to figure out what emotional state you’re in, he explains. Running away from a bear—or screaming at a concert—tells it that you must be scared. If you commit to standing still, in a relaxed state, on the other hand, you’ll send a message to your brain that there’s no need to get too excited. That can help encourage memory formation.
Kraft, meanwhile, prefers to remove any pressure from the equation, and to simply focus on having a great time. He’s a Swift fan, but like many of us, wasn’t able to secure tickets to the Eras Tour. If you’re in the same boat, take comfort: “I’m sorry that we both aren’t going,” he says. “But we would have forgotten it anyway.”