Thank you for welcoming me.

I don't know much about brain waves myself. From what I do know is that brain has electrical impulses which can be observed with instrumentation. They appear as waves but I don't know that there is anything really wave like in the biological function.

The impulses come from different parts of the brain. The waveforms could be associated with a part of the brain and/or the functional operation the brain preforming. Sometimes the clock speed of region changes and this would indicate a different operation is being preformed, often related to states of consciousness.

Wikipedia say that theta wave may come from the medial septal which works in conjunction with the nucleus accumbens. Amphetamine is said to effect the nucleus accumbens which in turn, I assume, regulates the medial septal.

Ordinarily there would be no need for "pleasure" in order for the medial septal to be regulated (I base this on the observation of "normal" people). It may just be that the nucleus accumbens or the medial septal defaults to the theta wave mode. Perhaps in such a way that there is no worldly stimulus or life experience that can turn the theta waves off. Then instead of reducing theta wave activity theta wave activity increases.

If that is true it may be possible to observe this with electrodes.