Sleep is essential for a variety of reasons, and now researchers from around the world have found another compelling reason to aim for eight hours of rest each night: it aids the brain in learning and retaining a new language.
Sleep is essential for a variety of reasons, and now researchers from around the world have found another compelling reason to aim for eight hours of rest each night: it aids the brain in learning and retaining a new language.
A research project spearheaded by the University of South Australia (UniSA) and published in the Journal of Neuroscience has shown that the synchronization of two electrical activities in a sleeping brain significantly boosts our ability to remember new vocabulary and intricate grammatical structures.
In this study involving 35 native English speakers, scientists monitored the brain activity of participants who were learning a simplified language known as Mini Pinyin, which is inspired by Mandarin but follows grammatical patterns similar to English.
One group of participants studied Mini Pinyin in the morning and came back in the evening for a memory test, while another group learned the language in the evening and spent the night in the lab, where their brain activity was recorded as they slept. The next morning, their learning progress was assessed.
The results showed that those who had slept afterwards performed much better than those who stayed awake.
Lead researcher Dr. Zachariah Cross, who completed his PhD at UniSA and is now at Northwestern University in Chicago, noted that the sleep-related enhancements were associated with the coordination of slow oscillations and sleep spindles—two brainwave patterns that synchronize during non-rapid eye movement (NREM) sleep.
“This synchronization likely indicates the transfer of learned information from the hippocampus to the cortex, improving long-term memory retention,” Dr. Cross explains.
“The brain activity observed post-sleep showed distinct theta oscillation patterns linked to cognitive control and memory consolidation, suggesting a strong connection between coordinated brainwaves during sleep and learning results.”
UniSA researcher Dr. Scott Coussens emphasizes that this study highlights the critical role sleep plays in mastering complex language rules.
“By revealing how particular neural processes during sleep boost memory consolidation, we shed light on the adverse effects of sleep disruption on language acquisition,” Dr. Coussens states. “Sleep is not merely a passive state; it is an active and transformative period for the brain.”
Moreover, these findings may have implications for developing treatments for people with language-related challenges, such as those with autism spectrum disorder (ASD) and aphasia, who often experience more sleep issues than the general population.
Research involving both animals and humans indicates that these slow oscillations enhance neural plasticity, which is the brain’s ability to adapt and change in response to various experiences and injuries.
“From this angle, increasing slow oscillations through techniques like transcranial magnetic stimulation could potentially speed up therapies for speech and language issues linked to aphasia,” Dr. Cross suggests.
Looking ahead, the researchers intend to investigate how the dynamics of sleep and wakefulness affect the learning of other complex cognitive tasks.
“Gaining insight into brain function during sleep could have far-reaching implications, beyond just language learning, potentially transforming how we approach education, rehabilitation, and cognitive training.”
