It has been years since I researched all this; actually began writing a book on the subject, but then life made its demands! Anyway, the light pulses will induce a waveform that looks like an alpha wave. But it is only induced--like ripples in a pond. I have a theory that if the induced waves can be made to synchronize with innate ones, then something unique might occur. But that is just my own, unconfirmed idea.

As to the images you see when falling asleep or waking up, those are well-known psychological phenomena called, respectively, hypnogogic and hypnopopic imagery.

I, too, can play around with the hypnogogic images, though it’s difficult to stay awake long when doing that. It is sure fun though, isn’t it?
If you are interested, take peek at my online art gallery:
https://seedpress.crevado.com/
Some of my early stuff is strongly influenced by phosphenes and sleep imagery.

Enjoy your neuroscience studies!