I've noticed minor hallucinations in a waking, sober state, usually they seem stronger if I focus on them and/or there is music (or a rhythmic predictable sound) present. While they are not at a point that they interfere with my life or have caused me any difficulty in disregarding. These hallucinations are nearly always visual in nature and very rarely auditory, usually manifesting as slow wave like movement seen in blank, plain or highly textured surfaces, such as a mono-colored wall, desk or patch of grass. On rare occasions I hear what sounds like someone speaking a word or 2 in another room, or sometimes brief unintelligible conversation or sounds of movement (like distant walking). This is fairly rare. less than a single occurrence per week and almost always happens when I ma alone in a comfortable location, such as my home. The visual hallucination however are always present though as stated, easily ignored and nearly unnoticeable unless focused on.

It's worth noting that I have used various psychedelic substances in my past and have also noticed (in the past) a temporary (roughly 1 to 2 day) reduction of symptoms after a singular use of dimethyltryptamine.

What kind of doctor should I consult about these issues? Could this be a symptom of a more serious issue?