You don't have to be a professional medium to sense the presence of Spirit, anyone can get this ability. And there are two types of onset - one onset later in life, and one early on. Think: like Type 1 and Type 2 diabetes. One has to do more with heredity and genetics (we think), and the other has more to do more with certain weatherings of life experience that make you more susceptible to it.
Ray Hyman discovered many methodological errors with Schwartz's research including; "Inappropriate control comparisons", "Failure to use double-blind procedures", "Creating non-falsifiable outcomes by reinterpreting failures as successes" and "Failure to independently check on facts the sitters endorsed as true". Hyman wrote "Even if the research program were not compromised by these defects, the claims being made would require replication by independent investigators." Hyman criticizes Schwartz's decision to publish his results without gathering "evidence for their hypothesis that would meet generally accepted scientific criteria... they have lost credibility."
After drawing your cards, revisit your initial question to ensure that it has been addressed properly. A good tarot guide can help you interpret the images you see on the tarot cards, but there’s really no substitute for personal reflection. As with any skill, practice makes perfect, so use this tarot tool often (daily, if possible), or order a set of Astrology Answers Master Deck Tarot Cards and practice at home!