Yes. You're right. I "studied" personality disorders, specifically narcissism and their symptoms/behaviors for a little while. My uneducated thesis is, there can be more to these behaviors than can be explained simply by dopamine. At least in the case of personality disorders, they often have very high intelligence. I think its more than just dopamine. 

To be clear, what I'm about to say is not excusing the behaviors, I want to help people defend from people with PDs, or even help the PDs.

It's also something I learned/experienced is, that I often don't believe people with PD's are fully aware of their behaviours and how they affect other people. Or they might but are very ashamed of it but dig deeper. Its a drug addict behavior. (there is a name for it but I cant remember)

Specifically for people that are not engaged in a power asymmetric relationship, it CAN be quite easy to learn about PD's behaviors and block/disarm them. Again most PD's are quite intelegent, they realize this, and are presented with 2 options: Stop because it doesn't work on you, or double down until you walk away. The more experienced generally take the former, younger or lower intelligence will often take the latter. 

My heart goes out to those in asymmetric power relationships with PDs and the like. Where when the PD is presented with the same choice, their decision to double down can cause some serious abuse to the lower power individual. 

You are now telling the affected person you have discovered their vulnerability and are using it to defend yourself. That's why it can be dangerous. This is why so much of psychotherapy treatments fail due to the patients insecurity and their toolkit (or lack thereof) used to overcome them. 

 I have dealt with many people with PD, all through my life, inside and outside family. It took me a while to understand and I have tried to learn about it to defend myself against it, since you tend to connect with people that have the energy that is familiar to you.

Rewire the brain and the emotional body takes time, and this people take a snapshot of you at first sight and they know which buttons to press.

It's fascinating.

Some are aware, others are not. Psychopaths are damn aware of what they are doing. 
Narcissist I don't think so, is a mechanics of self defense. Of course if NPD his pared with another cluster B, they can be somehow aware. At least they have the perception that things don't go well to them. That's why one of their most common frases are "How dare you ?" And the face expression let you know that they are shocked in disbelief. It's not fake  

 >I have dealt with many people with PD, all through my life, inside and outside family. It took me a while to understand and I have tried to learn about it to defend myself against it, since you tend to connect with people that have the energy that is familiar to you.

Exactly me too. I'm not to ashamed to admit it's likely my insecurities (especially body image) that attracted them in the past. 

> Some are aware, others are not. Psychopaths are damn aware of what they are doing. 
Agreed (arguably be definition :P)

>Narcissist I don't think so, is a mechanics of self defense.
Exactly my experience too! 

 I am not ashamed also. Even when people tell me "you should have put your boundaries up"!
What boundaries? No one teached me what boundaries are ..lol
Only who have been through it and came to a place of awareness, can understand.

This was a very interesting conversation. I was a target for lack of boundaries. I was the scapegoat of the family.
 

 Yup! I didn't understand what the term boundaries even meant until a few years ago. But now I realize boundaries are a tool than can help both people even if they don't know it yet. 

I am a think outside the box person, (sometimes creative), an idea guy or dreamer if you like. I think that becomes an easy target. If you are miserable and insecure, nothing is more fun than popping other people's dreams. I will also admit I'm not immune to this behavior too but I'll stop here before it gets too personal :) 

 It feels so good to talk to someone that does understand! 
Yes, let's stop here!
Thank you for your time 🙌 

 No need to thank me for time, if anything I'd say the reverse is in order. I appreciate the kind regards, but I don't want anyone to leave feeling like they owe me, even a thank you. I chatted because I wanted to and I enjoy meaningful conversations. Reach out any time! 

 Time is the most valuable asset...
I do not say thank you that much or lightly, but I felt in my heart to say it. 
Allow yourself to receive it. 🙌 

 >It's a reflexion of the person that does it, not of the receiver end.

My response is also to your point. This takes a long time to learn, but it is the best superpower anyone has against (for the sake of argument) "manipulative people" (including PDs and non PDs) 

But I do also believe Occam's razor presents itself again. I don't think most people (especially adults) that aren't in romantic relationships (or courtship and the like) intend to manipulate the other.

I simply think most people are just "lazy". I know I can be. Lazy to respond because what you said may not have been a high priority for them. Keyword PRIORITY. If it takes energy, especially though, you'll get left on read. It's not malice intent. So your job as the initiator is to know this and make them adjust their priorities (tell them you want an answer), or let it go.  

To beat this as a "lazy" person from my example above, is to just do something about it asap. If someone sends you a message or phone call, immediately rank it's priority, then respond in a reasonable time, with SOME answer. My experience in customer service has been exactly this. Tell them something, even if it's not what they want to hear. It just conveys to the other person you did in fact take the time to care to them personally, even for a moment. And lets them know where you stand on that priority list.