Keep in mind that depression and anhedonia can be started by a dopamine deficit as well. How would you feel pleasure in life, if you can not get a reward in your brain for anything you are doing(and would that not make you depressive in the long term?)? Remember, even though there is no trigger for reward if dopamine is low, you still can experience emotional pain. I would also look into that direction. Check out my posts about mucuna pruriens seed powder (stay away from extracts!!) to check if lack of dopamine is the cause.
I know for a fact that I have problems with low dopamine. The thing is, there is some evidence that excess acetylcholine inhibits dopamine and therefore causes the symptoms I have. CILTEP, caffeine, dopamine releasing agents - they all help increasing DA, but also increase NE, which is not good if you have problems with anxiety.
Antihistamines with anticholinergic properties are not an option, due to the extreme sedation.
Physostigmine, a cholinesterase inhibitor which increases central acetylcholine levels, has been
found in man to decrease manic symptoms, antagonize methylphenidate-induced behavioral
activation, and induce severe depression and psychomotor retardation in marijuana intoxicated
normals. In the current study, physostigmine was found to increase depressed mood in patients
with an affective component to their symptoms (manics, depressives, and schizoaffectives).
Schizophrenics without an affective component did not become depressed. After physostigmine
administration, all subject groups showed a significant increase in symptoms including lethargy,
slowed thoughts, withdrawal, apathy, decreased energy, decreased thoughts, motor retardation,
and feeling drained, indicating a state of psychomotor retardation; and all became less
cheerful, friendly, and talkative. The above information is compatible with the hypothesis that
acetylcholine may be involved in the etiology of affective disorders.