Do Asthmatics Really Sneeze at Plastic Flowers?

Do asthmatics really sneeze at plastic flowers, presuming them to be real?

So a variety of papers, books, and websites -- many of them arguing that the mind is "immaterial" -- would have you believe. Just to list a few:

James Le Fanu, in his 2009 book Why Us? How Science Rediscovered the Mystery of Ourselves, writes (p. 219): "it is well recognised, for example, that asthmatics sneeze in the presence of plastic flowers, presuming them to be real", but he gives no citation.

Kenneth R. Pelletier, in a chapter "Between mind and body: stress, emotions and health" in a 1993 Consumer Reports book edited by D. Goleman and J. Gurin entitled Mind Body Medicine: How to Use Your Mind for Better Health, claims in the very first line of his article that "Asthmatics sneeze at plastic flowers" (p. 19). He gives no citation, but repeats this claim in his 1995 book Sound Mind, Sound Body: A New Model for Lifelong Health, writing (p. 79): "Control is the vital link between mind and body. It is the pivotal point between psychological attitudes and our physical responses. Asthmatics sneeze at plastic flowers."

Anees A. Sheikh, in his 2002 book Healing images: the role of imagination in health quotes Pelletier, as does Max Velmans, in a paper entitled How could conscious experiences affect brains? that appeared in the Journal of Consciousness Studies 9 (11) (2002), 3-29.

Arthur V. N. Brooks, in a paper presented at the Philosophical Club of Cleveland in 1993, asks "Why do asthmatics sneeze at plastic flowers?" No citation is given.

Christopher Gilbert, a physician currently at Kaiser Permanente in San Francisco, writes in a 1998 article in the Journal of Bodywork and Movement Therapies that "Asthma attacks, for example, can be set off by plastic flowers if the individual has had asthma responses to flowers in the past, and believes the flowers are real."

Naomi Judd, in her 1994 autobiography Love Can Build a Bridge, writes (p. 449) that "The mind is the deepest influence on the body. Asthmatics have been known to sneeze at plastic flowers." She seems to be citing Pelletier (1993).

A 1923 address by W. Langdon Brown that appeared in Proc. Roy. Soc. Med. 16 (1923), 1-16. He says, "That asthma often occurs in neuropathic families, and that asthmatics are unduly suggestible, are well-known facts. The paroxysm excited by an artificial flower figures in every text-book."

And what appears to be the original citation is an 1886 paper entitled "The production of the so-called "rose cold" by means of an artificial rose", by John Noland Mackenzie, in the American Journal of the Medical Sciences.

With all these citations, it would certainly seem to be a fact, right?

Not so fast.

First, single anecdotal examples (like that given in the 1886 paper) are not very convincing. There are lots of reasons other than psychological ones why someone allergic to flowers might sneeze in the presence of a plastic flower - such as, for example, having an allergy to plastic or residues of chemicals used to make plastic. That's why a controlled study would be needed to be truly convincing.

Second, Neville J. King, in the Journal of Behavioral Medicine 3 (2) (1980), 169-189, wrote, "The classical conditioning of human asthma attacks also has yet to be reliably demonstrated. Despite the many anecdotal cases of human asthma attacks elicited by the sight of dust and artificial flowers (Dunbar, 1954; McGovern and Knight, 1967) which are consistent with a classical conditioning model of asthma, attempts at the classical conditioning of human asthma in the laboratory have not been successful. Of approximately 100 asthmatic patients, Dekker et al. (1957) could succeed in classically conditioning asthma attacks to apparatus used in allergy investigations in only 2 of these patients. Also, Knapp (1963) reported negative findings after a careful and elaborate series of experiments on conditioned asthma in human beings. As Purcell and Weiss (1970) concluded in their review, "it appears accurate to state that, with either animals or human beings, the successful conditioning of asthma remains to be demonstrated, even in the opinion of those investigations whose original positive reports on conditioning are cited frequently" (p. 607).

Asthma is a common disease with a strong genetic component. If you have two asthmatic parents, your chances of developing asthma are about 1 in 2. Asthmatics react to various allergens and to infections of the upper respiratory system. In the 1930's, under the influence of Freud's batty ideas, many people claimed asthma was due to "separation anxiety", a claim that has since been discredited. Later, it has been claimed by some doctors that asthma was just a conditioned response, but as we have seen, this has not been demonstrated rigorously.

All in all, I am skeptical of the claim that asthmatics sneeze at plastic flowers. Even if it were true, I don't see how it supports the claim that the mind is "immaterial". I know very little about neuroscience, but it doesn't seem that farfetched to me that an neural network could, after repeated stimulation, associate some autonomic response such as sneezing, with some visual stimulation. No supernatural explanation seems to be required.