A new study has revealed for the first time how the brain can precisely adapt to external stimuli, amounting to a breakthrough in our understanding of brain stimulation therapies.
A team of researchers at the University of Minnesota Twin Cities showed that non-invasive brain stimulation can change a specific brain mechanism that is directly related to human behaviour.
For the study, published in Nature Communications, researchers used what is called “transcranial alternating current stimulation”, otherwise known as brain modulation, to modulate brain activity.
By applying a small electrical current to the brain, the timing of when brain cells are active is shifted. This modulation of neural timing is related to neuroplasticity, which is a change in the connections between brain cells that is needed for human behaviour, learning, and cognition.
Alexander Opitz, University of Minnesota biomedical engineering associate professor, stated: “Previous research showed that brain activity was time-locked to stimulation. What we found in this new study is that this relationship slowly changed and the brain adapted over time as we added in external stimulation.
“This showed brain activity shifting in a way we didn’t expect.”
This result is called “neural phase precession.” This is when the brain activity gradually changes over time in relation to a repeating pattern, like an external event or in this case non-invasive stimulation. I
n this research, all three investigated methods – computational models, humans, and animals – showed that the external stimulation could shift brain activity over time.
“The timing of this repeating pattern has a direct impact on brain processes, for example, how we navigate space, learn, and remember,” Opitz said.
This technique can increase or decrease brain activity, but is most powerful when it targets specific brain functions that affect behaviours. This way, long-term memory as well as learning can be improved.
The long-term goal is to use this technique in the treatment of psychiatric and neurological disorders.
Opitz hopes that this discovery will help bring improved knowledge and technology to clinical applications, which could lead to more personalized therapies for schizophrenia, depression, Alzheimer’s disease, and Parkinson’s disease.
