It has long been known that the human brain generates various types of waves – electrical impulses. This is similar to the operation of a primitive radio receiver. Using electroencephalography (EEG), you can record the speed and sequence of brain activity. Like calm or turbulent waves on water, brain vibrations rise and fall at different frequencies, each associated with a particular state of mind.

Beta waves occur when the brain is fully involved in the process, such as during a conversation. Alpha waves are slow and usually appear when a person is about to rest. Of particular interest to scientists are the so-called theta waves, which have not yet been thoroughly studied.

Theta waves are high-amplitude brain waves with a frequency of 3 to 12 Hz per second. They are commonly associated with deep relaxation, drowsiness, and early stages of sleep. Previous research has shown that such waves appear when we disconnect from the outside world: during a long trip, running, taking a shower. Scientists suggest that theta activity is also associated with intuition and creativity – when ideas suddenly come to mind or when we dream, meditate. At the same time, all phenomena occur both in the waking state and during sleep, and their functions are still a mystery.

However, new study scientists from the University of Arizona could be the first step to unraveling. A series of trials was conducted with 12 volunteers suffering from epilepsy. Their body, unfortunately, did not respond to drug treatment. Each already had up to 17 electrodes implanted in the brain to search for the source of seizures.

First of all, volunteers were offered a task related to virtual navigation through the shopping center using an Xbox joystick. It was necessary to memorize the location of six different stores and then find the way to a certain place. Next, a memory test was conducted: the participants were asked to mentally recreate the route to the target store, marking the beginning and end of the path with the “A” button on the controller.

To make sure the test subjects actually imagine the route and not just relax, “control trials” were added. For example, in one of them, people were asked to imagine a path from their bedroom to the kitchen. According to statistical analysis, the time spent by each participant was correlated in both tasks. So, they really imagined the route, and not just dreamed.

Brainwave analysis showed that both navigation and mental simulation generated theta waves, which increased as the trial progressed. Just remembering the route generated much more activity that lasted longer. The results were consistent for each individual volunteer or electrode.

The discovery could hold the key to improving memory during aging or supporting patients with mental disorders such as dementia. Theta wave regulation could also be a new way to treat complex neurological conditions, including Alzheimer’s disease and stroke.

Already are being studied different methods of brain stimulation: from electrical to magnetic, and the first results look encouraging. Only time will tell if we will be able to use this potential to solve previously intractable medical problems.