Has someone been able to change their personality through lucid dreams? For example being normally more aggressive or restrained, or emotionless. Is there some kind of power you can tap into during dreaming in order to effect changes on your subconscious? Could this be dangerous? Would the results be gradual or sudden? Would it feel natural?
Emotionless? I wouldn’t think so, but small changes could work. If you in your lucid dream would stand infront of a big controllpanel representing you, with levers and buttons. Imagine all levers being set on medium, and above each lever there’s a label like “Emotional”, “Agressive” or “Selfconfidence”. Now simply pull each lever, either up or down.
Now would it feel sudden? I don’t know, I guess it would since we ain’t talking about medicines or anything else, we’re talking direct change or your mind (That sounds quite serious, but it really isn’t).
I do not think one is able to make any changes with any meaning without big knowledge of and experience with oneself.
Doing something like pulling a lever and expecting to become aggressive seems far fetched. I don’t think you can change your personality that easily. But you can probably use it symbolically to strengthen your resolve to be that way and thereby making it a little easier to switch to aggressive mode (or whatever you want to be)
You do better to decide what you want to be like and act like that in your lucid dreams alot. Wich is basically how you do it IRL, but dreams are a safe environment, you can try out different behaviours and see if you like it.
I don’t think you quite got my idea. You see, everything is in your mind, so if I believe that the lever represents my aggressiveness, and I pull it, it will now be in my mind that “I pulled that lever, my aggressiveness is on low”.
It’s possible to perform some slight personnality modifications. The principle is acting on your emotions. This has been (briefly) described by Patricia Garfield in Creative Dreaming and in some tibetan buddhists texts. In a LD, you’ll generally react very spontaneously and it will depend on your normal RL behavior. For instance, if you’re agressive, you’ll fight against every DC you don’t like.
By modifying consciously this behavior towards DC’s in LD’s, you’ll be able to modify your RL behavior. Thus when you’ll face IRL a situation in which you’re generally angry (or anguished, etc.) if you have taken the habit of not reacting so in LD’s, you’ll be able to see the negative emotion appear, to stop it immediatly and act more quietly. It’s the principle of behavioral psychology, yet in LD’s. Moreover, it doesn’t require any deep psychological knowledge.
Yet the problem is you have to practice this a lot in LD’s, and from my own experience, I’ve the feeling that it tends to disappear when you have less LD’s. 
About the lever, it could be an interesting trick, why not?
I feel like this could mess you up or make you a vegtable. Well i am thinking anything you can do in dreaming like changing your personality if you put your mind to it you can do it in real life.
KingOmar. I don’t think it’s anything to worry about. If it is at all possible to make radical changes in your personality, I think it would take a lot of doing. And you wouldn’t purposely mess yourself up, would you? Unless you wanted to, in wich case, you got what you wanted.
In my opinion, personality changes occur from experience of different situations that make you think about yourself and how you relate to everything. Particularily failure I think, because it prompts you to change.
That’s why dreams are such a good place to reinvent yourself, you can experience anything.