An international team of neuroscientists from Switzerland and the United Kingdom has reported a breakthrough in deep, non-invasive brain stimulation techniques that can modulate brain activity without penetrating the organ. The findings were published in Nature Neuroscience.
The researchers explored transcranial transient interference electrical stimulation, or tTIS, as a way to influence neural activity in the striatum. This brain region is linked to a range of neurological and psychiatric conditions, including stroke, anxiety, depression, Parkinson’s disease, and other neurodegenerative disorders.
In the study, 45 healthy volunteers of varying ages participated. The first phase involved 15 teenagers performing a finger-tapping sequence while brain activity was tracked with functional magnetic resonance imaging, or fMRI.
During the experiments, tTIS was used to modulate activity in the striatum, altering the firing patterns of neurons in that area.
The second phase included both older and younger groups, with mean ages around 66 and 26 respectively. They repeated the same finger task but faced a more complex sequence and shorter preparation time.
Results indicated improved motor performance under brain stimulation in both cohorts. The improvement was especially notable among older participants, who showed more than a 30 percent increase in finger-tapping accuracy compared with those who did not receive stimulation.
Researchers also demonstrated that the stimulation’s effectiveness depended on concurrent task-related brain activity. When the brain was at rest, stimulation of deep regions did not produce the same effects.
Overall, scientists believe this approach could pave the way for new therapies targeting disorders tied to neural activity patterns, offering a non-invasive option to influence brain networks in a controlled manner.
Earlier work from other research groups has explored neural stimulation to address tremor-related conditions, highlighting a growing interest in non-invasive neuromodulation as a therapeutic strategy [Citation: Nature Neuroscience study; related research on tremor suppression].