Similar principle applies here as well. What they do in this treatment is use high frequency light on the scalp. No, it doesn’t hurt or anything. At max, if your scalp is very sensitive, you might feel a little spark shock for a moment. For that, you can get the strength of the frequency adjusted so that you are comfortable with it.
The instrument either in form of a comb or a single rod which is in fact a glass electrode which when placed in the holder creates the low current and lets it flow through it. You can see the blue light in the electrode. When the electrode touches the scalp, you feel a light tingling sensation and a very comfortable and soothing vibration on the scalp.
High-frequency treatment uses low-current high-frequency alternating currents, delivered via a glass electrode. Because the high frequency current converts some of the oxygen in the air into ozone, the treatment has a germicidal action, and is also drying and warming. Consequently the treatment is used to aid healing, and also to help desquamation (the skin’s natural exfoliation), and simulate sweat and sebaceous glands.
At up to 250,000 Hz frequency, the hollow glass electrode behaves like a glow discharge tube, and is sometime called a “violet ray” or “violent wand”, (though the colour depends on the gas in the glass). Two electrodes are not required, and sparking may occur when the electrode is close to the skin. Because the effect may be pleasurable, similar devices are used in erotic electrostimulation. [Source: Wikipedia]
Moreover, the tingling and the vibration improves the blood circulation in the scalp and helps revitalizing the dormant hair follicles. This leads to better hair growth, controls hair loss, helps with dandruff issues as well. Also, the treatment in done in the hair spas so as to ensure better absorption of the treatment serums like hair growth serum or dandruff serums.
In fact, Punam also told me that this treatment is available for skin as well. It helps with breakouts and acne. The electrode is touched on the breakout and the effect is almost immediate. The pimple/acne is gone by the end of day or two. But, she also said that once we stop taking this treatment, the acne does come back. So, its kind of a curable treatment rather than a preventive measure.
I did think that whether its the same case with the hair as well but I think its more of a helpful treatment for hair because it can revive the dormant hair follicles which once revived and taken care of are not likely to become dormant again. It also helps relieve itchy scalp.