I looked up Raman spectroscopy on wikipedia. I think they're shooting a laser at the working area of the electrodes to observe the wavelengths of scattered light. It appears to me that they are applying a kind of molecular emissions spectroscopy where they excite their sample region with a chosen wavelength of laser to excite the molecules in the region. The molecules enter a higher energy state, due to laser excitation, and when they "come back down" to a lower energy level the emit light of different wavelengths which may be analyzed. Also the emissions spectra of disassociated protons and OH radicals will have their own character that can be observed.

I suppose that they observe a different emissions spectra when they're making noise and electrolyzing than when they aren't making noise. I sure hope that they're not affecting their experiment with their use of their laser because it surely is a wavelength that can affect water molecules.

Anyways it doesn't appear to involve alkaline treated noodles as far as I can tell.

For the record: I did not notice the strange emissions spectra of my gas combustion trial soon enough. I saw a funny colour that wasn't the usual purple hue and said "huh"... Then my eyeballs, sinuses, and lungs were getting fried when I took my next breath as my brain assimilated it's findings a few seconds too late.