No, this sixth sense has nothing to do with seeing dead people. In fact, this kind of sixth sense involves something called magnetoreception; the ability for a being to be able perceive magnetic fields of our earth.
There are several other species of animals that use this ability to navigate their way across long distances. They are able to do this by aligning themselves with the magnetic field which essentially gives them a sense of direction where the direction north is.

Geophysicist, Joe Kirschvink from the California Institute of Technology, has been experimenting with humans to see how capable we are of accessing this magnetic sense. He states:

"It's part of our evolutionary history.Magnetoreception may be the primal sense."

This "compass" is about all the information we have on how to operate this sixth sense within ourselves. However, scientists and researchers aren't exactly sure how one is suppose to use, sense, and retrieve data in order to actually tap into this sense. Which means this is pretty well speculated by everyone. In fact, there could be more than just navigation when it comes to this kind of ability. Perhaps animals use it to stalk prey, flee certain areas, or a variety of other possibilities.
Just in a recent study that Kirschvink published in the journal titled: Nature Communications,claims that there is a protein within the human retina, when introduced into the anatomy of fruit flies, can potentially have the ability to see the magnetic fields. This study suggests that this is potentially a magneto sensor, but for the way humans are able to use it is still unclear.
This kind of research has brought out the best and worst in other individuals who have opinions on the sense. Steven Reppert, researcher located at the University of Massachusetts Medical School, states to LiveScience: "It poses the question, 'maybe we should rethink about this sixth sense. It is thought to be very important for how animals migrate. Perhaps this protein is also fulfilling an important function for sensing magnetic fields in humans."
Furthering this type of study, Kirschvink tested individuals by sending a rotating magnetic field through the subject while measuring their brainwaves. As a result, Kirschvink had discovered that when this field was rotated counterclockwise, neutrons would react to the change in rotation within their brains, a visible spike in their electrical activity was shown. This means that there must be some kind of magnetic sense within humans.
Of course, there are still a variety of questions that people have about this kind of study. There is a lot open to interpretation for people to speculate whether or not this sixth sense actually exists. There should be multiple more studies involved within the near future on humans to clarify this sense that we've never honed or tried to notice before until now.
What do you think about this idea? Do you really believe that humans might have a sixth sense after all? Do you think we should continue exploring this side of ourselves to enhance our knowledge of the world around us?