Thync works by pulsing small electrical currents, no more than about 20 milliamps, through nerves on the head. A sticky strip of electrodes attaches to places where nerves run close to the skin above the right eyebrow, behind the ear, and on the back of the neck. A small triangular device connects above the eyebrow, and sends electrical pulses out through the electrode strip. According to Jamie Tyler, Thync’s CSO and other co-founder, the effect of pulsing currents along these nerves is to modulate norepinephrine production in the brainstem at the back of the head. The device has two main modes—called “vibes” in Thync-speak—calm and energy. The difference between these two is that energy increases the release of norepinephrine, increasing alertness, whereas calm decreases it.
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