Extrasensory Perception ESP

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Extrasensory Perception (ESP)

• Lecture 7
• Parapsychology
• Paul Staples

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Overview

• What is ESP?
• Telepathy
• Clairvoyance
• Precognition and Retrocognition
• Experimental evidence
• Restricted-choice experiments
• Free-response experiments
• The process approach
• Summary

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Learning Objectives

• This session will enable you to
• Give a reasonable definition of ESP
• Categorise the various types of ESP
• Understand the nature of the experimental
  evidence available
• Appreciate the criticisms and counter-criticisms
  of some of the findings
• Appreciate the difference between
  resticted-choice and free-response scenarios
• Recognise that there are other considerations,
  such as those suggested by the process approach

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What is ESP?

• Extrasensory perception (ESP) is perception that
  occurs independently of the main physical senses
  (sight, hearing, touch, taste and smell or,
  indeed, perceptual processes such as
  proprioception)
• In some ways the term is vague but it is
  generally used to imply a source of information
  that is unknown to modern science
• ESP can be divided into a number of sub-categories

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Telepathy

• For telepathy the source of information is
  another persons mind
• The principle requirement of telepathic
  transmission is that the information transfer
  cannot be explained by any known physical process
• Often the demonstration involves information
  transfer over large distances
• Unlike physical information transfer, telepathy
  is not subject to the weakening of the signal the
  further you move away from the source

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Clairvoyance

• Clairvoyance is similar to telepathy except that
  the source of the information is an object or
  event rather than another mind
• As well as clairvoyance, we can propose
  clairaudience where the source of information is
  auditory rather than visual
• Clairaudience is an alleged psychic ability to
  hear things that are beyond the range of the
  ordinary power of hearing, such as voices or
  messages from the dead

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Precognition and retrocognition

• If the clairvoyance or clairaudience concerns
  things in the future or the past the these are
  referred to as precognition and retrocognition
  respectively
• Dreams have sometimes been related to
  precognition and characters like Nostradamus are
  famous for their precognitive visions
• Retrocognitions can be about recent events (e.g.
  the perpetrator of a recent murder) or distant
  events (e.g. historic events)
• Retrocognition is different from past life
  regression

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Experimental evidence

• ESP experiments fall into two broad categories
• Restricted-choice experiments
• The receiver must make a decision about what is
  being transmitted from a small set of known
  possibilities
• Zener cards are an example of restricted choice
  stimuli
• Free-response experiments
• Here the sender will choose an item from a large
  but finite set of possible stimuli
• The receiver is not told anything about the
  nature of the chosen stimulus
• The remote viewing you participated in was a
  free-response set up.

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Restricted-choice experiments

• In the 1930s one of the most prominent places for
  ESP research was the Rhine laboratory in America
  established by J B Rhine
• A typical study from that era is the Pearce-Pratt
  experiment
• Typical card-guessing experiment using zener
  decks (25 cards, 5 target alternatives, MCE 5)
• 74 runs conducted over 37 sessions
• Sender and receiver (Pratt and Pearce) in
  separate buildings (100 or 250 yards apart)

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Restricted-choice experiments

• Watches synchronised so that when Pratt turned
  over a card, Pearce made a guess
• Both recorded their sequences
• Hits counted independently by Rhine
• Rhine present with Pratt during last few sessions
• Mean hits per run was significant at p lt 10-22
• No likelihood that results were due to chance

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Restricted-choice experiments

• Hansel (1961) criticised the study by suggesting
  that as no-one was with Pearce during the
  sessions, he could have gone out of his room and
  looked through a window at Pratts cards.
• This could not be shown to be wrong until 1967
  when Stevenson was able to locate the original
  blueprints
• However, on scrutinising the official and
  unofficial reports of the experiments there are
  inconsistencies in the number of hits recorded

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Restricted-choice experiments

• Pratt-Woodruff experiment (1939)
• 2,400 runs across 32 volunteers
• Mean hit rate was 5.21, p lt 0.00001
• However, the result attributable to only 5 of the
  32 volunteers
• Pavel Stepanek
• Library clerk from Czechoslovakia
• Took part in 27 studies across 18 investigators
• Was discovered through his ability to state
  whether the white or dark side of a thin piece of
  cardboard was face up inside an opaque envelope
• Performance level at around 57 correct, plt10-6

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Restricted-choice experiments

• Bill Delmore
• Yale law student in the early 1970s
• Unusual in that he had vivid visual imagery,
  frequent lucid dreams (knowing you are dreaming)
  and a high degree of confidence in his psi
  abilities
• 520 playing cards mixed and placed in desk
  drawers
• Experimenter picked a card and without looking at
  it placed it in an opaque folder
• 46 runs of 52 trials each (2392 trials)
• Delmore had an excess of exact hits! For exact
  hits p lt 10-30
• Delmore was also successful on other tasks

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Free-response experiments

• Remote viewing (RV) experiments
• Puthoff and Targ were the first to do this in the
  late 1970s
• They worked with Uri Geller whom most
  parapsychologists quickly became suspicious of
• Their first work was with Pat Price, a
  Californian police commissioner
• Target location chosen from a pool of 100
• Target observed for 30 minutes
• Price asked to verbally describe and to draw the
  location
• Nine trials
• Independent judge taken to each site and then
  asked to rank the drawings from 1 to 9 according
  to their similarity to the site
• Seven were ranked first at the correct site (p lt
  10-4)

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Free-response experiments

• Critics of these experiments are Marks and
  Kammann (1980)
• They suggested that there were biasing clues in
  the transcripts of the verbal descriptions
• Now some of the judges failed to correctly
  identify matches
• Also, only the most successful trials were chosen
  for publication and this falsely increased the
  statistical result
• However, there have been a number of successful
  RV experiments reported in the literature

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Free-response experiments

• Ganzfeld Experiments
• We have already talked about the Ganzfeld
  procedure
• It has become a popular method of testing ESP
• Honorton (1978) claimed that 23 out of 42
  ganzfeld experiments had yielded statistically
  significant results
• Successful results came from 9 independent labs
• Taken as a collection of results the evidence
  seems quite impressive

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Free-response experiments

• In the 1980s, Hyman criticised the findings on
  several grounds
• Experiments had small numbers of participants and
  may only have been submitted for publication if
  the data were significant
• Scoring procedures varied widely across the
  studies
• In experiments using multiple conditions only one
  had to be successful for a positive claim to be
  made
• One-tailed tests were used even though
  psi-missing outcomes (the other tail) were
  considered as successes (i.e. a success was
  recorded for a score significantly different from
  chance whether it be better or worse than chance)

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Free-response experiments

• Honorton countered these criticisms by
  recalculating the results in line with the
  criticisms
• The level of success was not compromised even
  though the success rates reported had been too
  high
• Other criticisms, such as one concerning the
  quality of the randomisation process, were
  conceded by Honorton

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Free-response experiments

• Overall, it would seem that the studies have been
  fairly rigorous even though improvements could
  have been made
• However, this is no more true here than it is in
  all other areas of human research
• Whilst the apparent ESP demonstrated so far may
  not compel one to accept ESP, the evidence does
  point to there being something worth further
  investigation

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The process approach

• All of the research considered so far is
  concerned with trying to establish proof of the
  existence of ESP
• Other research tries to increase our
  understanding of psi anomalies
• Some may consider this approach premature until
  the proof has been verified

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The process approach

• The process approach looks at the following
  aspects that need to be considered
• Cognitive processes right hemisphere, cognitive
  capacity.
• Belief in ESP sheep and goats
• Personality traits extraversion/ESP correlation
• The experimenter effect experimenters get
  significant results in psi experiments because
  ofexperimenter error, psychology and psi
  hypotheses.
• It attempts to explore the degree to which these
  factors interact with ESP
• There is not time to explore these aspects
  further here

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Summary

• We have seen that there is some convincing data
  concerning the possible existence of ESP
• The data are not yet at the stage where they
  provide unequivocal proof of the existence of ESP