You are half right.
But its not manipulation of human psychology, but understand and predict How humans Will react to certain events.
Prices dont follow Any model. Prices only change when people are buying or selling.
The models that exist around prices (technical analysis) are statistics models based on what happened on the past (what happened in the past when certain numbers matched).
It is kind of a crap shot, but its a probability crap shot.
Some models give you more probability of winning, other are bullshit.
The hard part is to understand wich is wich.
Before following a technical indicator signal (or a "technical analyst") you need to understand what the indicator mean.