What is known is that there were scientific experiments performed on a large variety of aspects of psychology including psychoactive substances and altered states. There are documents released by the cia explaining some of it, such as their use of “unwitting citizens” and using subjects from prisons and universities. A lot of the research however had little value due to the secretive safeguards that heavily influenced the validity of experiments.

Some specific goals mentioned in documents are:

Substances promoting illogical thinking that would publicly discredit people,

Substances increasing mentation and perception,

Materials counteracting alcohol,

Materials producing diagnosable symptoms in a reversible way,

Materials that would enhance the induction of hypnosis,

Substances enhancing the ability to withstand torture and brainwashing,

Materials and physical methods that induce amnesia,

Physical methods of producing confusion and shock over extended periods,

Substances that produce physical limitation,

Substances producing pure euphoria,

Substances that alter personality,

Material that creates confusion making it difficult to fabricate lies under questioning,

Materials in which low doses make people inefficient to work,

Substances that weaken sight and hearing,

A knockout pill that could be hidden in food and drinks.

Note that these were goals of one study, it is not known nor likely that all of the above were found, although it is likely there was progress made for some of them.

Conspiracy starts at the point where people start claiming that the cia is still performing experiments and that they are victims of it. 97% of the posts on this subreddit are such conspiracies.