Ganzfeld studies of ESP: Sargent et al (1979)
Each P arrived at the lab and were offered drinks and music played for a relaxed atmosphere. When they were ready to start, they were asked to fill in a short, questionnaire, then, asked to lie on a mattress, half ping-pong balls and cotton wool taped over their eyes, headphones playing white noise, a red light shinging onto the ping pong balls.
The sender was usually the experimenter, a friend of the experimenter or a student who 'sent' the image from Sargent's office. There were 27 sets of four pictures labelled A, B, C and D, chosen by the experimenter so there were no links between them. A complicated method of randomisation was used to determine the image to be sent.
At the end, the P was asked to go to Sargent's office and rate all four pictures that had been sent on a scale of 1-100. The sender was then asked to disclose what image had been sent. A hit was identified by the P giving the target image the highest score out of 100. 6/12 sessions were hits, much more than the 25% expected by chance alone.
Blackmore found between session 8-9, two sets of envelopes disappeared from the drawer in the office. Also, during session 9, Sargent entered the receivers room to 'help' as the participant was saying very little. Interestingly, on this same trial, Sargent made an arithmetic 'mistake', recording the session as a direct hit when it was not.
a. Have early findings been replicated?
- Some researchers claim that because of more stringent controls (i.e. Auto Ganzfeld) the claims of early researchers are not supported.
b. Is it the experimental design that is having the effect?
- This idea points up the differences between 'free' and 'forced' choice. Forced = Chosing from a given list. Free = No stimulus material to choose from. Free appears to be fairer nbut brings in the issue of trust in the 'sender' participant.
Honorton and Ferrari (1989) Meta Analysis:'Forced' - found huge significant effect in favour of ESP
Milton (1997) Meta Analysis:'Free' - found huge significant effect in favour of ESP.
NB: Results are stronger for studies using the Ganzfeld techniques, so does this mean that the semi-scientific way of measuring ESP is effective or is it the design (rather than the IV) that it producing the result?
NB: The 'file drawer' effect. Meta analysis may omit studies with unsupported results.
Ganzfeld Controversies Part II
c. Do particular participants (receivers) give better results?
Dalton (1997) - Ps with prior experience give better results. - Ps who meditate give better results. - Ps with prior lab experience give better results. - Ps scoring higher on 'feelings/perception' on the Myers-Briggs indicator give better results. Overall, it appears sensitive participants give better results.
IDA BIOLOGICAL APPROACH - People have different sensitivity to sensory stumuli; one person's threshold (over which stimulus must go in order to be registered) is lower than anothers, and so they are more biologically sensitive.
Smith (2003) - Experimenters who are sympathetic (sensitive) to ESP give better results than those who aren't.
Auto Ganzfeld: Bem and Honorton (1994) After a series of trials, success=33%, well above chance.
Evaluation of Ganzfeld studies
- There is still a danger with Ganzfeld of bias occuring, where believers in paranormal experiences produce seemingly positive findings. Results from Ganzfeld studies tend to match researchers beliefs.
- Findings from meta-analyses depend on which studies were excluded. Therefore, establishing the existence (or not) of ESP cannot be achieved in this way, illustrating the need for well-designed studies, with procedures agreed by everyone involved in advance.
- The fact that receivers guess above chance is indisputable, but arguments rage over whether psychic energy is transferred.
- The use of Ganzfeld techniques has led to the introduction of more rigorously controlled, unbiased research techniques in mainstream psychology.
There is a difference between Macro and Micro PK:
Macro PK: Is direct and observative manipulation of objects e.g. spoon bending
Micro PK: Is less obvious/smaller and indirect effects e.g. affecting the throw of a dice.
Psychokinesis (PK) Research
a. Schmidt (1969) invented an electric coin flipper. He found a significant effect when Ps were asked to mentally affect the flip. However, not all participants could do this. Are we back to certain participants giving better results?
b. Randi (1995) set up a test for Uri Gellar, who claimed to have the ability to bend spoons at will, on the Jimmy Carson 'Tonight Show', so he could prove his spoon bending abilities. Gellar complained that he 'didn't feel strong' when it came to performing. Randi, referring to the fact that Gellars 'effect' could be had via conjuring tricks said, if Uri Gellar bends spoons with divine powers, then he's doing it the hard way.
c. Radin and Ferrari (1991) reviewed 148 studies by 52 researchers involving 2569 participants about influencing the throw of a dice. Overall, a significant positive result was found. However, only 69 studies were controlled for biased dice and taking these 69 into account, overall results were weaker but still significant.
Evaluation of Psychokinesis (PK)
- Parapsychologists often complain that the standard of proof required for their studies to be accepted a valid is unfairly higher than in other areas of psychology but Abelson (1978 said that 'extraordinary claims require extraordinary explanations'.
- For psychokinesis to be accepted there is need for conclusive experiments, free of any possible error or fraud, and immune to all sceptical doubt.
- Rao and Palmer (1987) believed that REG experiments can be seen as 'conclusive', as they minimise, as much as possible, any chances of fraud or error. Such tests produce significant results, but, somewhat inevitably, are still criticised and not accepted, as although there is evidence for the existence of PK, independant researchers generally cannot replicate findings.
The ganzfeld experiments illustrate the fact that many techniques within modern parapsychology adopt a cognitive approach. ESP, if it exists, is seen as being simply another type of information processing and many parapsychological experiments are similar in rationale and methodology to standard cognitive experiments, the only difference being that all normal modes of information transfer are exluded.