In vivo phase-dependent enhancement and suppression of human brain oscillations by transcranial alternating current stimulation (tACS)
David Haslacher,
Asmita Narang,
Rodika Sokoliuk,
Alessia Cavallo,
Philipp Reber,
Khaled Nasr,
Emiliano Santarnecchi,
Surjo R. Soekadar
Affiliations
David Haslacher
Clinical Neurotechnology Laboratory, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
Asmita Narang
Clinical Neurotechnology Laboratory, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
Rodika Sokoliuk
Clinical Neurotechnology Laboratory, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
Alessia Cavallo
Clinical Neurotechnology Laboratory, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
Philipp Reber
Clinical Neurotechnology Laboratory, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
Khaled Nasr
Clinical Neurotechnology Laboratory, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
Emiliano Santarnecchi
Precision Neuroscience and Neuromodulation Program & Network Control Laboratory, Gordon Center for Medical Imaging, Massachusetts General Hospital & Harvard Medical School, Boston, MA, USA
Surjo R. Soekadar
Clinical Neurotechnology Laboratory, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; Corresponding author.
Transcranial alternating current stimulation (tACS) can influence perception and behavior, with recent evidence also highlighting its potential impact in clinical settings, but its underlying mechanisms are poorly understood. Behavioral and indirect physiological evidence indicates that phase-dependent constructive and destructive interference between the applied electric field and brain oscillations at the stimulation frequency may play an important role, but in vivo validation during stimulation was unfeasible because stimulation artifacts impede single-trial assessment of brain oscillations during tACS. Here, we attenuated stimulation artifacts to provide evidence for phase-dependent enhancement and suppression of visually evoked steady state responses (SSR) during amplitude-modulated tACS (AM-tACS). We found that AM-tACS enhanced and suppressed SSR by 5.77 ± 2.95%, while it enhanced and suppressed corresponding visual perception by 7.99 ± 5.15%. While not designed to investigate the underlying mechanisms of this effect, our study suggests feasibility and superiority of phase-locked (closed-loop) AM-tACS over conventional (open-loop) AM-tACS to purposefully enhance or suppress brain oscillations at specific frequencies.