Rhythmic Brain Simulations to Elevate Cognitive Function
Our attention, our memories, our mind. These things guide us in every moment of every day, consciously and unconsciously. Cognitive function, the ability to learn, solve problems, and use stored information, is key for development and growth. This is why diseases like dementia and other neurological diseases, which affect cognitive function, are so dangerous. Currently, medications remain the first step in treating neurological diseases. Although scientists continue to develop drugs that show more and more success, this is not the only path we should pursue. No matter how advanced medication gets, the blood-brain barrier prevents the brain uptake of most pharmaceuticals. Thus, it’s crucial for scientists to explore alternative solutions.
Researchers at Boston University are doing just that. The team has studied the effects of an emerging brain simulation technology - transcranial alternating current simulation (tACS), on different mental functions in patients and in healthy people. tACS utilizes electrodes that are attached to a person’s head to deliver weak electric currents at very specific frequencies to very specific brain regions. The currents aim to fire neurons in a coordinated rhythm, forcing different brain cells to coordinate with each other. By externally inducing a certain rhythm, tACS can promote healthy brain activity and function when the brain cannot do so itself.
Before recent studies, scientists disagreed on the effectiveness of tACS. Some studies have found positive changes in brain activity and function with tACS. Other studies suggested that the electrical currents were too weak to show any real change in cognitive function. In response to conflicting data, a meta-analysis was conducted, which combines the results of multiple studies. The meta-analysis conducted for tACS involved 100 published studies and over 2,800 human participants.
After combing through all the studies, the analysis found consistent and immediate improvements in mental function with tACS. The strongest improvements were seen specifically in attention span, memory, and the ability to adapt to new information. The analysis suggests that tACS could be beneficial to restoring cognitive function in the short term.
Researchers also found that tACS can target two regions of the brain at the same time and can control how they communicate with each other to reduce or amplify a certain function. This could be particularly useful in treating mental health issues like depression and bipolar disorder which tap into multiple parts of the brain to under or over-stimulate the reward processing system.
tACS developments are bringing scientists closer to developing non-invasive treatments for neurological diseases without using medications. Researchers even hope that as tACS progresses, they may be able to tailor the rhythms at which the electrical currents are delivered to cater to the specific needs of a patient. Currently though, tACS shows promise in helping people regain cognitive function.
