Alignment with brainwave rhythms accelerates learning in adults

Abstract: Tuning into a person’s brainwave cycle before performing a learning task can dramatically improve the rate at which cognitive skills improve.

Source: University of Cambridge

Scientists have shown for the first time that briefly adjusting a person’s individual brain wave cycle before performing a learning task dramatically increases the rate at which cognitive skills improve.

Calibrating the rate of information delivery to match our brain’s natural pace increases our ability to absorb and adapt to new information, according to the team behind the study.

University of Cambridge researchers say these techniques could help us retain “neuroplasticity” much later in life and enhance lifelong learning.

“Each brain has its own natural rhythm, generated by the oscillation of neurons working together,” said Prof. Zoe Kourtzi, senior author of the study from Cambridge’s Department of Psychology. “We simulated these fluctuations to keep the brain in tune with itself—and in the best state to flourish.”

“The plasticity of our brain is the ability to restructure and learn new things, constantly building on previous patterns of neural interactions. By exploiting brain wave rhythms, it may be possible to enhance flexible learning across the lifespan, from childhood to older adulthood,” said Kourtzi.

The findings, published in the journal Cerebral cortexwill be researched as part of the Center for Lifelong Learning and Personalized Cognition: a research collaboration between Cambridge and Nanyang Technological University (NTU), Singapore.

Neuroscientists used head-mounted electroencephalographic – or EEG – sensors to measure electrical activity in the brains of 80 study participants and sample brain wave rhythms.

The team read the alpha waves. The middle range of the brainwave spectrum, this wave frequency tends to dominate when we are awake and relaxed.

Alpha waves oscillate between eight and twelve hertz: a full cycle every 85-125 milliseconds. However, each person has their own peak alpha frequency within that range.

The scientists used those readings to create an optical “pulse”: a white square that flashes against a dark background at the same rate as each person’s individual alpha wave.

Participants were given a dose of personalized 1.5-second pulses to force their brains to work in their natural rhythm – a technique called “entrainment” – before being faced with a tricky high-speed cognitive task: trying to identify specific shapes within barrage of visual chaos.

A brain wave cycle consists of a peak and a trough. Some participants received pulses that corresponded to the peak of the waves, some to the bottom, while some received rhythms that were either random or at the wrong speed (slightly faster or slower). Each participant repeated more than 800 variations of the cognitive task, and the neuroscientists measured how quickly people improved.

The learning rate for those who were involved in the real rhythm was at least three times faster than for all other groups. When the participants returned the next day to complete another round of tasks, those who learned much faster maintained a higher level of performance.

“It was exciting to discover the specific conditions you need to get this impressive boost in learning,” said first author Dr Elizabeth Michael, now at Cambridge’s Department of Cognition and Brain Science.

“The intervention itself is very simple, just a short flicker on the screen, but when we hit the right frequency and the right phase alignment, it seems to have a strong and lasting effect.”

It is important that the input pulses must be matched with the depth of the brain waves. Scientists believe this is the point in the cycle when neurons are in a “high receptivity” state.

“We feel like we’re constantly watching the world, but in fact our brains take quick snapshots, and then our neurons communicate with each other to put the information together,” said co-author Prof. Victoria Leong, from NTU and Cambridge’s Department of Paediatrics. .

“Our hypothesis is that by synchronizing information delivery with the optimal phase of brain waves, we maximize information capture because that’s when our neurons are at peak excitability.”

Previous work from Leong’s Baby-LINC lab shows that the brain waves of mothers and babies will synchronize when they communicate. Leong believes the mechanism in this latest study is so effective because it mirrors the way we learn as infants.

“We tap into a mechanism that allows our brains to match the temporal stimuli in our environment, particularly the communication cues like speech, gaze and gestures that are naturally exchanged during parent-infant interactions,” Leong said.

“When adults talk to young children, they adopt child-directed speech – a slow and exaggerated form of speech. This study suggests that child-directed speech may be a spontaneous way of speed-matching and engaging children’s slower brain waves to support learning.”

The researchers say that although the new study tested visual perception, these mechanisms are likely “domain general”: applicable to a wide range of tasks and situations, including auditory learning.

They argue that the potential applications for brainwave entrainment may sound like science fiction, but they are increasingly achievable. “Although our study used complex EEG machines, there are now simple headband systems that allow you to measure brain frequencies fairly easily,” Kourtzi said.

“Children now do a large part of their learning in front of a screen. One can imagine using brainwave rhythms to improve aspects of learning for children who struggle in mainstream classrooms, perhaps due to attention deficit.”

Other early applications of brainwave entrainment to promote learning could include training in professions where rapid learning and quick decision making are vital, such as pilots or surgeons. “Virtual reality simulations are now an effective part of training in many professions,” said Kourtzi.

“Implementing brainwave-synchronized pulses in these virtual environments could give new learners an advantage or help those retraining later in life.”

About this novelty of learning research

Author: Fred Lewsey
Source: University of Cambridge
Contact: Fred Lewsey – Cambridge University
Picture: Image attributed to Cambridge University

Original research: Open access.
“Learning at the Rhythm of Your Brain: Individualized Entrainment Promotes Learning for Perceptual Decisions” Zoe Kourtzi et al. Cerebral cortex

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Abstract

Learning at the Rhythm of Your Brain: Individualized Entrainment Promotes Learning for Perceptual Decisions

Training is known to improve our ability to make decisions when interacting in complex environments. However, individuals differ in their ability to learn new tasks and acquire new skills in different environments. Here, we test whether this variability in learning ability is associated with individual brain oscillatory states.

We use a visual flicker paradigm to engage individuals in their own brain rhythm (ie, peak alpha frequency) as measured by resting-state electroencephalography (EEG). We show that this individual frequency-matched entrainment of the brain results in faster learning in a visual identification task (ie, detecting targets embedded in background clutter) compared to entrainment that does not match the individual’s alpha frequency.

Furthermore, we show that learning is specific to the phase relationship between the attractive jitter and the visual target stimulus. EEG during entrainment showed that individualized alpha entrainment enhances alpha power, induces phase alignment in the pre-stimulus period, and results in shorter latency of early visual evoked potentials, suggesting that brain entrainment facilitates early visual processing to support improved perceptual decisions.

These findings suggest that individualized brain entrainment can promote perceptual learning by altering gain control mechanisms in the visual cortex, suggesting a key role of particular neural oscillatory states in learning and brain plasticity.