Transcranial Alternating Current Stimulation
Conditions
Brief summary
In this study on healthy subjects, the effect of transcranial alternating current stimulation (tACS) will be investigated. In particular, the distinction between periodic and aperiodic electroencephalogram (EEG) activity will be considered, as well as the state-dependency phenomenon. Participants will take part in two experimental sessions that will include tACS stimulation (one real, one control). Before, during, and after stimulation, subjects will have their EEG recorded during rest or during tasks. The aim of this study is to investigate how the modulatory effects of gamma-tACS interact with intrinsic neural activity, measured in terms of periodic and aperiodic activity, as well as neurophysiological and behavioral modulation, taking into consideration the state-dependency phenomenon, which refers to the brain's activation state prior to stimulation.
Interventions
DEVICEreal tACS
tACS is a non-invasive method to induce brain modulation. It will be applied at a frequency of 40 Hz (gamma-tACS) with a peak-to-peak intensity of 2 mA. During the real tACS condition, the alternating current will be administered for 20 minutes.
DEVICEsham tACS
In the sham tACS condition, the current will be delivered only for the first 30 seconds and then stopped, in order to simulate the same somatosensory sensations as real tACS, but without inducing modulation.
Sponsors
IRCCS San Camillo, Venezia, Italy
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
\- Healthy adults
Exclusion criteria
* Common
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| resting-state electroencephalography (EEG) signal | baseline | The periodic and aperiodic activity of the EEG signal will be estimated through Brainstorm (i.e., EEG analysis software) and quantified in terms of numerical values representing the periodic/aperiodic component of the EEG signal. The periodic and aperiodic activity of the EEG signal will be assessed during three time frames: baseline, during the intervention, and immediately after the intervention (real or sham tACS) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| behavioral performance (response times) | baseline | Participants' motor performance at a computerized task will be measured in terms of response times (how fast the participants press a computer button, according to the task's instructions). The participants' motor performance will be assessed during two time frames: baseline and immediately after the intervention (real or sham tACS) |
| behavioral performance (accuracy) | baseline | Participants' motor performance at a computerized task will be measured in terms of accuracy (% of correct responses at the computerized task, according to the task's instructions). The participants' motor performance will be assessed during two time frames: baseline and immediately after the intervention (real or sham tACS) |
| auditory steady state response (ASSR) | baseline | The auditory steady state response will be measured via EEG during entrainment through exposure to amplitude-modulated 40Hz sounds (5 min, sequence of amplitude-modulated tones at 40 Hz, delivered via earplug binaurally). The auditory steady state response will be measured as power of the EEG gamma band. The auditory steady state response will be assessed during two time frames: baseline and immediately after the intervention (real or sham tACS) |
Countries
Italy
Outcome results
None listed