Good memory depends on the speed of brain waves
Our ability to store information for everyday use depends on the speed of theta brain waves, according to a study published by PLOS Biology and carried out by an international research team led by Vincenzo Romei, Professor at the Psychology Department of the University of Bologna.
The rhythmic electrical activity produced by the human nervous system can be visualized and recorded in pulses known as brain waves, classified according to their frequencies in hertz, corresponding to different phases of brain activity.
According to a hypothesis proposed by psychologists and neuroscientists, the speed of theta waves, ranging between 4 and 7.9 hertz, would be responsible for the ability to manage information. To test this theory, the researchers simulated, through electric stimulation, the neuronal activity of 32 subjects, using a technique known as “Transcranial Alternating Current Stimulation”, able to affect electrical brain activity.
“The aim of this stimulation approach is to model the oscillatory activity of the brain regions that are active during the memorization process”, explained Vincenzo Romei. “By comparing the working memory capacity during simulated and real stimulation, we found that slow theta stimulation enhanced working memory capacity while fast theta stimulation reduced it. It is as if we had changed the size of the sheet of paper on which we normally note down our shopping list”.
The change in working memory capacity is only temporary but the results of the study could help to better understand brain function and improve the treatment of memory problems typical of old age.