According to new research from the University of California, Davis, the entrainment of theta brain waves with a commercially available device not only enhances theta wave activity, but also boosts memory performance. The findings appear in the journal Cognitive Neuroscience.
The entrainment of theta brain waves with a commercially available device boosts memory performance. Image credit: Gerd Altmann.
Electrical activity in the brain causes different types of brain waves that can be measured on the outside of the head.
Theta waves occur at 5-6 cycles per second, often associated with a brain that is actively monitoring something.
In an earlier study, University of California, Davis’ Professor Charan Ranganath and co-authors found that high levels of theta wave activity immediately before a memory task predicted better performance.
“Entrainment devices use a combination of sound and lights to stimulate brain wave activity. The idea is that oscillating patterns in sensory inputs will be reflected in brain activity,” the researchers explained.
“The devices are marketed to address a range of problems such as anxiety, sleep issues, ‘low mood’ and learning.”
“However, there is very little published scientific evidence to support these claims.”
The scientists obtained a commercially available theta-wave entrainment device (DAVID PAL 36 by Mind Alive, Inc., Edmonton, Canada) and decided to test it.
They had 50 volunteers either use the device for 36 minutes, or listen to 36 minutes of white noise, then do a simple memory test.
The subjects who had used the device showed both improved memory performance and enhanced theta wave activity.
They repeated the experiment with another 40 volunteers, but this time the control group received beta wave stimulations.
“Beta waves are a different type of brain wave pattern, occurring at about 12 to 30 cycles per second, associated with normal waking consciousness,” Professor Ranganath and colleagues said.
“Once again, theta wave entrainment enhanced theta wave activity and memory performance.”
The team conducted a separate study using electrical stimulation to enhance theta waves.
However, this actually had the opposite effect, disrupting theta wave activity, and temporarily weakened memory function.
“We’re surprised the devices work as well as they appear to do,” Professor Ranganath said.
“What’s surprising is that the device had a lasting effect on theta activity and memory performance for over half an hour after it was switched off.”
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Brooke M. Roberts et al. 2018. Entrainment enhances theta oscillations and improves episodic memory. Cognitive Neuroscience 9 (3-4): 181-193; doi: 10.1080/17588928.2018.1521386
