|'Karma' is an eastern concept (primarily Indian) which states that your actions will be reflected back to you by the universe sooner or later. (The related western concept of 'cause and effect' states that you reap what you sow.)
A deeper and more accurate concept is that of 'instant karma', which states that everything is One, and everything you do - you do to yourself.
However, since we believe that we are separate from one another, we tend not to notice the effects of our behavior. This slows down the 'instant karma'. We tend to make the same mistakes over and over again, and when we finally realize what we are doing, all the built up 'karma' hits us all at once.
Your thoughts, your feelings, your actions affect you both directly and indirectly. The degree of openness and the attitude you assume how fast the karmic wheel turns for you. A psychic generally operates from a higher state and that means a fast turnover - you'll notice the potential results of your actions almost immediately. When you act from a state of greater openness, your actions are 'dharma'.
For a psychic the concept of 'karma' plays a two-fold role: the first is about one's own spiritual and psychic progress, and the second is about the ability of psychic prediction. If you are familiar with the karmic forces, personal psychic prediction is super easy: take a good look at the present and you will see the consequences that will manifest to a greater degree in the future.