Time, like a relentless stream, carries our experiences, leaving memories etched along its shores. We can’t and don’t remember everything that happens to us, which is where emotions come in: they help to anchor the experiences worth keeping to a place and time. At UCLA, psychologists have embarked on an intriguing journey, exploring how music’s emotional currents shape these memory landscapes.

Their findings, published in Nature Communications, reveal the potent role of music in transforming ordinary moments into indelible memories.

“Changes in emotion evoked by music created boundaries between episodes that made it easier for people to remember what they had seen and when they had seen it,” said lead author Mason McClay, a doctoral student in psychology at UCLA.

“We think this finding has great therapeutic promise for helping people with PTSD and depression.”

The role of music in recollection

Our brains face an onslaught of information, necessitating a system to sift and store. Here, two mechanisms come into play: one weaving memories into coherent episodes, the other setting them apart over time. This dynamic process is akin to organizing items into storage boxes, with emotions serving as efficient organizers, bolstering memory retrieval.

“When we need to retrieve a piece of information, we open the box that holds it. What this research shows is that emotions seem to be an effective box for doing this sort of organization and for making memories more accessible,” said corresponding author David Clewett, an assistant professor of psychology at UCLA.

In the study, participants listened to different kinds of music that elicited varied emotions — joyous, anxious, sad, or calm feelings — while viewing neutral images. These images depicted some of the most mundane things possible, such as pictures of a watermelon slice, a soccer ball, or a wallet. The researchers assessed moment-to-moment changes in emotional state related to music by using a novel tool that tracked the computer mouse movement.

The experiment took an intriguing turn when, after a distraction task, participants were presented with pairs of these images randomly. They were then asked to recall not only the sequence of these images but also their perceived time intervals. Remarkably, objects viewed around moments of emotional shifts — be they mild, moderate, or intense — were remembered as being more temporally distant than those seen during emotionally stable periods. Furthermore, these emotional transitions seemed to disrupt the participants’ ability to remember the order of the images.

Emotional shifts and memory perception

McClay draws a fascinating parallel, suggesting that emotionally charged moments, like those in Queen’s ‘Bohemian Rhapsody’, might be perceived as lasting longer than less emotional experiences of similar duration. “Musicians and composers who skillfully intertwine emotional events to craft a narrative may be shaping our memories to feel longer and more temporally rich,” McClay explains.

The study also found that the nature of the emotional transition played a significant role. Positive emotional shifts led to better memory integration, with participants recalling the sequence of events more accurately and perceiving them as closer in time to each other. In contrast, transitions toward negative emotions seemed to stretch the perceived time between new memories.

The following day, participants’ long-term memory recall showed enhanced recall of items and moments linked with emotional changes, particularly those associated with intense positive emotions. This suggests that positive and high-energy feelings can bind different aspects of an experience together in memory, offering intriguing insights into the interplay between emotion, music, and memory.

The researchers next want to investigate whether this insight can be used for therapy. Studies have shown that music used in a mental health therapy setting can help patients feel relaxed and enhance positive emotions.

“If traumatic memories are not stored away properly, their contents will come spilling out when the closet door opens, often without warning. This is why ordinary events, such as fireworks, can trigger flashbacks of traumatic experiences, such as surviving a bombing or gunfire,” Clewett said. 

“We think we can deploy positive emotions, possibly using music, to help people with PTSD put that original memory in a box and reintegrate it, so that negative emotions don’t spill over into everyday life.”