Breathing rhythms help strengthen memories during sleep

There’s something both captivating and comforting about the rhythms and harmonies of a symphony orchestra, right? Well, did you know that something similar happens inside your brain while you’re catching some sleep? It turns out, our brains have a maestro of their own – breathing.

Just as a conductor harmonizes an orchestra to create a symphony, breathing synchronizes the rhythm of brain waves during sleep. This phenomenon takes place in the hippocampus – a region of the brain that is critical for memory.

Breathing rhythms during sleep

This fascinating revelation comes from a recent study by Northwestern Medicine. It marks the first time scientists have linked breathing rhythms during sleep to the hippocampal brain waves known as slow waves, spindles, and ripples.

Study senior author Christina Zelano is a professor of neurology at Northwestern University Feinberg School of Medicine.

“To strengthen memories, three special neural oscillations emerge and synchronize in the hippocampus during sleep, but they were thought to come and go at random times,” noted Professor Zelano. “We discovered that they are coordinated by breathing rhythms.”

Science behind memory synchronization

The study shows that certain brain waves, called hippocampal oscillations, align with specific phases of the breathing cycle. These oscillations are critical for organizing and strengthening memories.

Andrew Sheriff is a postdoctoral student in Zelano’s lab and the corresponding author of the study.

This means that the rhythm of your breathing during sleep plays an active role in helping your brain store and recall information effectively.

“Memory consolidation relies on the orchestration of brain waves during sleep, and we show that this process is closely timed by breathing,” explained Sheriff.

This research opens new doors for understanding the intricate relationship between breathing, brain activity, and memory.

Breathing, sleep, and memory consolidation

The connection between sleep and improved memory is not a new discovery. The ancient Roman scholar Quintillion stated: “The interval of a single night will greatly increase the strength of the memory.”

This phenomenon, now recognized as memory consolidation, involves the precise coordination of brain waves in the hippocampus.

Sheriff shared a personal example to explain how memory consolidation works. While attending a conference in Reykjavik, Iceland, he had to find his way around an unfamiliar city.

After sleeping, he realized his sense of direction and understanding of the city’s layout had improved. This improvement happened because, during sleep, the brain replayed and reinforced the experiences and maps he had formed earlier.

His hippocampus, which is responsible for spatial memory, used specific brain waves to process and solidify this information overnight.

“The hippocampus plays a major role in forming a map of a new area,” Sheriff said. “I would wake up and feel I had a better representation of the city around me. That was facilitated by the oscillations that occurred during my sleep, which we found are coordinated by breathing.”

Implications for sleep disorders

The study’s findings carry significant implications for individuals suffering from sleep-disordered breathing, such as sleep apnea. Poor memory consolidation is one of the many cognitive challenges associated with such conditions.

“When you don’t get sleep, your brain suffers, your cognition suffers, you get foggy,” Sheriff noted. He emphasized the connection between disrupted breathing during sleep and serious conditions such as stroke, dementia, and neurodegenerative diseases like Alzheimer’s.

Interestingly, the unique rhythm of breathing during sleep may serve a specific purpose. “If you listen to someone breathing, you might be able to tell when they are asleep, because breathing is paced differently when you’re sleeping,” Sheriff said.

“One reason for that may be that breathing is performing a careful task: coordinating brain waves that are related to memory.”

New frontier in sleep research

The research highlights the importance of addressing sleep disorders to maintain cognitive health and memory. Sheriff emphasized the need for individuals with disrupted breathing to seek treatment, as improved sleep could have far-reaching benefits for overall brain function.

This study was funded by the National Institute on Deafness and Other Communication Disorders and a Ruth L. Kirchstein Institutional National Research Award.

This remarkable research adds a new layer of understanding to the intricate processes that occur during sleep. By uncovering the role of breathing in synchronizing brain waves, Northwestern scientists have paved the way for new interventions aimed at improving memory and cognitive health.

The study is published in the journal Proceedings of the National Academy of Sciences.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–