Sleep is essential for various reasons, and a group of international researchers has identified a new reason to prioritize getting eight hours of rest each night: it supports the brain in acquiring and retaining a new language.
Sleep is essential for various reasons, and a group of international researchers has identified a new reason to prioritize getting eight hours of rest each night: it supports the brain in acquiring and retaining a new language.
A study conducted by the University of South Australia (UniSA) and published in the Journal of Neuroscience has shown that two specific electrical activities in the brain during sleep can significantly enhance our ability to learn new vocabulary and intricate grammar.
In their experiment with 35 native English speakers, scientists observed how participants learned a simplified language called Mini Pinyin, which is inspired by Mandarin but has grammatical structures similar to English.
Half of the participants learned Mini Pinyin in the morning and returned later that day for a memory test. The other half studied the language in the evening and then stayed overnight in the lab, where their brain activity was monitored while they slept. They were assessed for their progress the next day.
The individuals who had a sleep period showed a marked improvement in their abilities compared to those who stayed awake.
Dr. Zachariah Cross, the primary investigator who earned his PhD at UniSA and is now affiliated with Northwestern University in Chicago, notes that the improvements linked to sleep are due to the synchronization of slow oscillations and sleep spindles—brainwave patterns that work together during non-REM (NREM) sleep.
“This synchronization probably represents the transfer of learned information from the hippocampus to the cortex, which boosts long-term memory retention,” says Dr. Cross.
“Neural activity following sleep displayed distinct patterns of theta oscillations connected to cognitive control and memory consolidation, indicating a solid connection between the co-ordination of brainwaves during sleep and learning effectiveness.”
Dr. Scott Coussens, a researcher at UniSA, emphasizes that the study highlights how crucial sleep is for mastering complicated language rules.
“By revealing how particular neural functions during sleep aid memory consolidation, we offer new insights into how sleep disturbances can affect language learning,” Dr. Coussens explains. “Sleep serves not only as a resting period but also as a transformative phase for the brain.”
The research findings may also have implications for developing therapies for individuals with language impairments, such as those on the autism spectrum (ASD) and those with aphasia, who often face more significant sleep issues than average adults.
Studies conducted on animals and humans demonstrate that slow oscillations enhance neural plasticity, which is the brain’s capacity to adapt and change in response to experiences and injuries.
“From this standpoint, it might be possible to enhance slow oscillations through techniques like transcranial magnetic stimulation to expedite speech and language therapy for aphasia,” Dr. Cross suggests.
In the future, researchers intend to investigate how the dynamics of sleep and wakefulness affect learning in other intricate cognitive tasks.
“Gaining insights into how the brain operates during sleep has far-reaching implications beyond language acquisition. It could revolutionize our methods for education, rehabilitation, and cognitive training.”
