Transcranial Alternating Current Stimulation (tACS) is a non-invasive brain stimulation technique that uses low-level electrical currents — delivered through electrodes placed on your scalp — to entrain or synchronize your brainwaves. It’s like giving your brain a gentle rhythmic nudge to help it function better. tACS sends a sinusoidal (wave-like) current through the scalp that matches the frequency of a specific brainwave (like alpha, theta, or gamma). The idea is to “tune” the brain by syncing it with the external frequency — kind of like setting a metronome for your neurons. By stimulating a specific frequency at specific locations, tACS aims to boost or suppress certain mental states.
How Does tACS Work?
- Electrodes are placed on the scalp, usually with conductive gel.
- A low current (usually <2 mA) is applied at a specific frequency.
- The current oscillates rhythmically, modulating brain activity underneath the electrodes.
- The brain begins to entrain to the external rhythm, kind of like syncing up with a beat.
Are there risks or side-effects with tACS?
- Can cause tingling or itching at the electrode site
- Rare: headaches, dizziness, fatigue
- Effects vary widely between individuals
Requires proper targeting – you want to match the right frequency and region
