II. Discourse Structure Test: (15%) Since the 1970s, parapsychologists at leading universities and research institutes around
the world have risked the derision of skeptical colleagues by putting the various claims for
telepathy to the test in dozens of rigorous scientific studies. The results and their
implications are dividing even the researchers who uncovered them.
Some researchers say the results constitute compelling evidence that telepathy is
genuine. Other parapsychologists believe the field is on the brink of collapse, having tried to
produce definitive scientific proof and failed. _________1____________ Reports of
telepathic experiences had by people during meditation led parapsychologists to suspect that
telepathy might involve 'signals' passing between people that were so faint that they were
usually swamped by normal brain activity. In this case, such signals might be more easily detected by those experiencing meditation-like tranquility in a relaxing 'whole field' of light,
sound and warmth.
The ganzfeld experiment tries to recreate these conditions with participants sitting in
soft reclining chairs in a sealed room, listening to relaxing sounds while their eyes are
covered with special filters letting in only soft pink light. In early ganzfeld experiments, the
telepathy test involved identification of a picture chosen from a random selection of four
taken from a large image bank. _________2____________
Once the session was over, this person was asked to identify which of the four images
had been used. Random guessing would give a hit-rate of 25 percent; if telepathy is real,
however, the hit-rate would be higher. In 1982, the results from the first ganzfeld studies
were analyzed by one of its pioneers, the American parapsychologist Charles Honorton.
They pointed to typical hit-rates of better than 30 percent - a small effect, but one which
statistical tests suggested could not be put down to chance.
The implication was that the ganzfeld method had revealed real evidence for telepathy.
But there was a crucial flaw in this argument - one routinely overlooked in more
conventional areas of science. Just because chance had been ruled out as an explanation did
not prove telepathy must exist; there were many other ways of getting positive results.
__________3___________ In response, the researchers issued a review of all the ganzfeld
studies done up to 1985 to show that 80 percent had found statistically significant evidence.
However, they also agreed that there were still too many problems in the experiments which
could lead to positive results, and they drew up a list demanding new standards for future
research.
After this, many researchers switched to autoganzfeld tests - an automated variant of
the technique which used computers to perform many of the key tasks such as the random
selection of images. By minimizing human involvement, the idea was to minimize the risk
of flawed results. In 1987, results from hundreds of autoganzfeld tests were studied by
Honorton in a 'meta-analysis', a statistical technique for finding the overall results from a set
of studies. Though less compelling than before, the outcome was still impressive.
Yet some parapsychologists remain disturbed by the lack of consistency between
individual ganzfeld studies. __________4___________ If, as current results suggest,
telepathy produces hit-rates only marginally above the 25 percent expected by chance, it's
unlikely to be detected by a typical ganzfeld study involving around 40 people: the group is
just not big enough. Only when many studies are combined in a meta-analysis will the faint signal of telepathy really become apparent. And that is what researchers do seem to be
finding.
What they are certainly not finding, however, is any change in attitude of mainstream
scientists: most still totally reject the very idea of telepathy. The problem stems at least in
part from the lack of any plausible mechanism for telepathy. Various theories have been put
forward, many focusing on esoteric ideas from theoretical physics. They include 'quantum
entanglement', in which events affecting one group of atoms instantly affect another group,
no matter how far apart they may be. While physicists have demonstrated entanglement
with specially prepared atoms, no-one knows if it also exists between atoms making up
human minds. Answering such questions would transform parapsychology.
_________5____________ Some work has begun already, with researchers trying to
identify people who are particularly successful in autoganzfeld trials. Early results show that
creative and artistic people do much better than average: in one study at the University of
Edinburgh, musicians achieved a hit-rate of 56 percent. Perhaps more tests like these will
eventually give the researchers the evidence they are seeking and strengthen the case for the
existence of telepathy.
(AB) This has prompted some researchers to argue that the future lies not in collecting
more evidence for telepathy, but in probing possible mechanisms.
(AC). The idea was that a person acting as a 'sender' would attempt to beam the image
over to the 'receiver' relaxing in the sealed room.
(AD) The limitations of the studies have undermined the reliability of their findings, and,
thus, invite more doubt.
(AE) Skeptics and advocates alike do concur on one issue, however, that the most
impressive evidence so far has come from the so-called 'ganzfeld' experiments, a
German term for 'whole field'.
(BC) These ranged from 'sensory leakage' - where clues about the pictures accidentally
reach the receiver - to outright fraud.
(BD)Defenders of telepathy point out that demanding impressive evidence from every
study ignores one basic statistical fact: it takes large samples to detect small effects.