A recent study in China found that alpha neurofeedback training improves visual working memory. The group that received this training improved both the capacity and accuracy of their visual working memory compared to the group that underwent sham training. The paper was published in npj Science of Learning.
Biofeedback training is a therapeutic technique that uses real-time monitoring of physiological functions, such as heart rate, muscle tension, and brainwave activity, to help individuals learn to control these processes consciously. The idea behind biofeedback is that if constant and accurate information is provided to an individual about their heart rate or brainwave activity, they will be able to identify actions that affect these processes and, through that, learn to control them. This technique is generally applied to bodily processes that humans cannot easily monitor using their consciously available senses.
Alpha neurofeedback training is a type of biofeedback therapy that aims to help individuals learn to increase their alpha brainwave activity. Alpha waves, typically associated with a relaxed and meditative state, are prevalent when the brain is calm but alert. In this way, participants effectively learn to remain calm but alert. This training is used to reduce anxiety, improve focus or overall well-being, and for various other purposes.
Study author Wenbin Zhou and his colleagues wanted to explore whether alpha neurofeedback training might improve visual working memory. Visual working memory is the cognitive system responsible for temporarily holding and manipulating visual information, such as shapes, colors, and spatial relationships, to perform tasks like problem-solving and decision-making.
It generally works through two phases: encoding, when the memory is formed, and maintenance, when the memory is kept in a state that allows easy recall. The authors note that previous studies already indicated that alpha neurofeedback training improved visual working memory, but it remained unclear which phase of the memory process the training affects.
Study participants were 40 healthy volunteers recruited from Shanghai Normal University, with an average age of 24 years. The study authors randomly divided them into two groups. One group underwent alpha neurofeedback training for five days, in five daily sessions.
In these sessions, while participants worked on a cognitive task (a modified Sternberg task), electroencephalographic data were recorded about their brain activity. Alpha wave activity derived from this data was presented to study participants as a blue bar, the height of which depended on the amplitude of the participant’s alpha waves. Participants were asked to find a way to keep the bar as high as possible. The other group completed a sham neurofeedback training in which they were presented with feedback based on a random electroencephalography frequency band.
Additionally, study participants completed working memory tasks (a modified Sternberg task, block tapping task, color-recall task) at the start of the study, a day after the end of the training, and on day 14 after the start of the study.
Results showed that there were no differences between the two groups on the modified Sternberg task. However, the alpha neurofeedback training group showed increased visual working memory capacity on the Corsi-block tapping test. They also showed improved visual working memory precision in one of the conditions of the color-recall test.
“These results suggest that alpha NF [neurofeedback] training influences performance in working memory tasks involved in the visuospatial sketchpad. Notably, we demonstrated that alpha NF training improves the quantity and quality of visual working memory,” the study authors concluded.
The study sheds light on the effects of alpha neurofeedback training on visual working memory. However, it should be noted that the number of study participants was very small and they were all young people. Additionally, the effects were obtained on 2 of the 3 tests. It remains unknown whether the improvements are specific for these tasks or more general in nature.
The paper, “Alpha neurofeedback training improves visual working memory in healthy individuals,” was authored by Wenbin Zhou, Wenya Nan, Kaiwen Xiong, and Yixuan Ku.
