Hi Matt,
Happy Easter to you and to your mom.
To answer your questions about too much and too little l-dopa - this is the theory as I understand it, if you take too little you are under medicated and the symptoms don't go away, if you take too much you could get symptoms very like PD emerge, and if you get it just right it should help....... it a goldilocks thing! However it isn't totally straightforward as depending on progression and duration of PD it can help more or less........ so the only thing to go on is if there is improvement, rather than the opposite. This may not all be apparent to the person with PD, for instance, they may always have thought they were smiling, and not realized that the smile was not visible to others, or they may have thought their voice was loud enough because it felt like enough effort was going into the talking......

If your mom is feeling and functioning better then is is probably visible, and your neuro, who won't have seen her for a while, is likely to be able to see that change. Good luck with the appointment,

Lindy