In terms of Ganzfeld Zimmer experiments (only sound isolation, no special light other than slight dimming of white light), that this way may provide better use:
1. Make sure the participants have open minds for it, that they are prepared to accept such, telepathy, or have a weak/strong suspicion towards it.
2. Make sure they are emotionally prepared, that they are told of the "respects toward own feelings routine" before entering the experiment and that this preparation can be academically improved, by a type of guidance, opposite sex/gender or not. There is also the question whether the participants should bring friends/acquaintances they are confident with, and I think this represents a good beginning, although, there are probably other ways that work too, Helsinki-Declaration in hand, general research ethics...
3. Some (para-)psychologists may have "strong opinions" on the outcome and are not fit or suitable for conducting this type of research, they should be removed from (every) possible set of researchers...
Importantly: There is also a bigger, tacit assumption to this "game" and it is how the senses/the feelings relate to this, FORCING the entire psychology onto a new direction by train rails, that a finding probably sends a battalion of idiots right out to where they belong...!!!
Important 2: That we go with alpha-numbers at 5% or lower, that the Zener cards are kept to 4, that the subjects are to choose a comfort zone as options provide inside the Ganzfeld-zimmers. That an outcome on 8% means success, if not the very numbers higher up!
Good luck!
Further note (beyond Good luck):
I find that lie-detectors can be useful as post-experiment control.
We may use these questions:
1. Have you done your best during this experiment? (Presumably yes.)
2. Have you been open to the question of telepathy? (Presumably yes.)
3. Are you convinced now to the question of telepathy? (Open to yes/no.)
Remember that the presence of lie-detectors can heighten the seriousness of the experiment (to some subjects, maybe not all).
Notes:
1. One book to start with, in determining a whole field of all, papers and books alike, all "meta-studies included", but intelligently... This book fx. has an ESP topic to it: http://www.amazon.ca/Introduction-Psychology-Dr-Rod-Plotnik/dp/0495903442/ - +/- page 139. Introduction to Psychology - Hardcover: 768 pages, Publisher: Wadsworth Publishing; 9 edition (Feb 25 2010), Language: English, ISBN-10: 0495903442, ISBN-13: 978-0495903444.
2. Urls: http://en.wikipedia.org/wiki/Ganzfeld_experiment
http://en.wikipedia.org/wiki/Telepathy (only Wikipedia for now, sorry.)
3. Remember to add the "Truthiness"-aspects...
as notion to the researchers themselves or others, by the questionnaires to the participants or so...
4. Here is an interesting link further: http://cassiopaea.org/forum/index.php?topic=26367.0 that includes "some views/findings" on the Ganzfeld studies altogether...
5. You know, when the god-d*mn sociologists can't f*cking relate to PRIMARY literature, sitting on a "golden degree" that they probably never should have had and poor in reading the very literature, if not the Scientology itself... then what about our "friends", the psychologists... Probably not all...