I'm an empath. Before the event when I was ten, I used to see colored cords connecting people to each other, to animals, to elements, to plants, to nature, to things (manmade objects), etc. The cords varied. Each color represented an emotion. The strength/vibrancy of the color signified how strongly someone felt. The thickness of the cord told me how long someone felt that way. Those are different to the cords that you're talking about. But when I was ten, I experienced a shift of the way I perceive things.. Now I can feel things, but cannot see in my mind's eye. Having learned and grown and progressed on my journey since then, I've been able to recognize other types of energy workings. They may very well be energy exchange, as Phoenix Raven Littlemoon has described. In my experiences, I've come across vampiric people. (Vampire, in my opinion, is one that can't produce enough of something, so must take it from someone or something else--another source). Some knowingly feed off of others. And some don't know that they're doing so. There is a couple of books, one called "Hands of Light", and the other called "Light Emerging". I can't remember the author's name right now (I just began reading it before I had a crazy busy week of doing nothing spiritually productive), but they talk about cords of light between people.