Psycholinguistics is actually the study of language from the psychological perspective. But I think a secondary definition should exist. It should read as follows:
Psycholinguistics [noun] speech or language that when used is guaranteed to make the listener go psychotic. See also fighting-words.
For me, several phrases pop into mind:
Who told you that you could _________?
Well, don't you think that ...
Who let you (do) ____________?
A reasonable person could only believe/think...
These push my buttons. I am an adult by many standard definitions. The idea that I require permission for any of the mundane activities of life or am required to think as the speaker (any speaker) dictates is repugnant to me in the extreme. The notion that I can be manipulated to change word, thought, or deed by use of these petty, brow-beating phrases is as insulting as it is absurd.
For example, from this evening, no one told me that I could tuck my jeans into my boots. I chose to tuck my jeans into my boots because I felt the jeans were slightly short and because tucking-in showed the good-looking boots to better effect.
For less recent example, a few years ago a baby-doc (that is, a doctor under the age of 35) expressed the following sentiment upon learning that my ob/gyn had provided me with my first Mirena IUD:
He let you get an IUD?
Strong emphasis on the let, moderate emphasis on the you.
So basically what I heard: I can't believe a doctor actually gave a dumb slut like you such a valuable medical device.
I wish my comeback had been more authoritative, but I was unaccustomed to that kind of tone from a medical professional. I think I feebly informed her that I had asked her for it and he had taken my request under consideration. Like I said, quite feeble.
For a more pervasive example, I have a work-related acquaintance who begins perhaps one-third of every sentence she speaks with a passive-aggressive variation on don't-you-think... I absolutely loathe that. The haughty tone is just the bonus plan. Like she cannot even conceive that this world may in some dark and shabby corner contain a thought that disagrees with the one she is about to suddenly and shrilly vomit into the room. I have terrific blood pressure. And yet, I literally feel the blood in my arms SMASH against the artery walls every time she does this.
So that's psycholinguistics for me. Tongue-in-cheek, you know. I bet a word already exists to describe the phenomenon. Shoot me a comment if you know it.