title: EEG mean frequency changes in healthy subjects during prefrontal transcranial direct current stimulation.
abstract: In this pilot study we evaluated electroencephalographic (EEG) mean frequency changes induced by prefrontal transcranial direct current stimulation (tDCS) and investigated whether they depended on tDCS electrode montage. Eight healthy volunteers underwent tDCS for 15 min during EEG recording. They completed six tDCS sessions, 1 wk apart, testing left and right direct current (DC) dipole directions with six different montages: four unipolar montages (one electrode on a prefrontal area, the other on the opposite wrist) and two bipolar montages (both electrodes on prefrontal areas), and a single sham session. EEG power spectra were assessed from four 1-min EEG epochs, before, during, and after tDCS. During tDCS the outcome variable, brain rate (fb), changed significantly, and the changes persisted for minutes after tDCS ended. With the DC dipole directed to the left (anode on the left prefrontal area or wrist), fb increased, and with the DC dipole directed to the right (anode on the right prefrontal area or wrist), fb decreased, suggesting asymmetric prefrontal cortex functional organization in the normal human brain. Anodal and cathodal effects were opposite but equally large. Gender left these effects unchanged.
authors.affiliation: Department of Neurological Sciences, "Sapienza" University, Rome, Italy; and neri.accornero@gmail.com.
authors.forename: Neri
authors.initials: N
authors.lastname: Accornero
authors.affiliation: Department of Neurological Sciences, "Sapienza" University, Rome, Italy; and.
authors.forename: Marco
authors.initials: M
authors.lastname: Capozza
authors.affiliation: Department of Psychology, "Sapienza" University, Rome, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Pieroni
authors.affiliation: Department of Neurological Sciences, "Sapienza" University, Rome, Italy; and.
authors.forename: Stefano
authors.initials: S
authors.lastname: Pro
authors.affiliation: Department of Neurological Sciences, "Sapienza" University, Rome, Italy; and.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Davì
authors.affiliation: Department of Neurological Sciences, "Sapienza" University, Rome, Italy; and.
authors.forename: Oriano
authors.initials: O
authors.lastname: Mecarelli
mesh_terms: D000328:Adult; D058256:Brain Waves; D004569:Electroencephalography; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D017397:Prefrontal Cortex / Q000502:physiology*; D065908:Transcranial Direct Current Stimulation
keywords: EEG; TDCS; brain rate; brain stimulation; prefrontal areas