Rubber hand illusion is being challenged

Psychological experiments pose a problem most of the time. They also have 'reproduction problems' because human psychology is highly complex  with several factors governing it. We now have one more psychology explanation facing a challenge.

Heard about Rubber hand illusion? If you didn't, first watch this video that explains it

Now this rubber hand illusion, a world-famous psychological experiment used to help explain the brain's understanding of the body, as well as scores of clinical disorders, has been dismissed as not fit-for-purpose in a new academic paper. 

The Rubber Hand Illusion, where synchronous brush strokes on a participant's concealed hand and a visible fake hand can give the impression of illusory sensations of touch and of ownership of the fake hand, has been cited in more than 5,000 articles since it was first documented more than 20 years ago.

In a new research paper Dr. Peter Lush, Research Fellow at the Sackler Centre for Consciousness Science at the University of Sussex, demonstrates that the control conditions typically used in the Rubber Hand Illusion do not do the job they need to do.

His results show that the commonly reported effects of the Rubber Hand Illusion can be attributed to imaginative suggestion'—otherwise known as 'hypnosis'.Dr. Lush is calling for the development of valid control methods for the Rubber Hand Illusion while raising the prospect that suggestion effects could confound many other effects throughout psychological science.

Last year Dr. Lush and colleagues reported in a paper, currently under peer review but available as a preprint on PsyArxiv, substantial correlations between response to the Rubber Hand Illusion and response to imaginative suggestion , or phenomenological control, in a large sample of 353 participants. This study shows that response to the Rubber Hand Illusion is, partially or entirely a suggestion effect.

Psychologists have long been aware of the dangers of 'demand characteristics'—in which subjects, often without realising it, say what they implicitly think they ought to say.

Dr. Lush's work takes these concerns much further by showing that how suggestible someone is can dramatically influence what people report in the Rubber Hand Illusion—and potentially in many other experiments too.

Dr. Lush said: "The extent to which phenomenological control confounds psychological science is currently unknown, but may be substantial. If the effects are widespread—and they may well be—psychology will be faced with a new crisis of generalisability."

In the new study, published this week in Collabra: Psychology, an innovative design was employed to test imaginative suggestion in rubber hand illusion reports.

Source: https://www.collabra.org/article/10.1525/collabra.325/