In this cross sectional survey of medical staff, we found that almost 70% had experienced phantom vibrations from an electronic device. The perceptions were most common among students and house staff and were associated with frequency of use. Most respondents found the sensations to be only mildly annoying, but 2% found them very bothersome. As a result, only 61% had tried to stop them, and most of those who tried succeeded in extinguishing the sensation—either by moving the device or refraining from using it in vibrate mode.

Comparison with other studies

This is the first report of this phenomenon that we are aware of in the medical literature. In a graduate thesis published in 2007 on “Emotional and behavioral aspects of mobile phone use,” David Laramie surveyed 320 adult mobile phone users and found that two thirds had experienced phantom rings,4 similar to the proportion we report. The study was reported in the popular press, and the condition is discussed on numerous blogs and eHealth sites. There are at least three phantom vibration syndrome groups on Facebook.

Just as the Holy Roman Empire was not holy, Roman, or an empire, phantom vibration syndrome does not involve a phantom, nor is it technically a syndrome. The sensations are better characterised as tactile hallucinations, in which the brain perceives a sensation that is not actually present. Because the word hallucination carries a connotation of mental illness, whereas the phantom vibration syndrome appears to occur in a majority of normal individuals, and because so many are already using the term, it seems appropriate to let the popular appellation stand.

The cause of phantom vibration syndrome has not been explored but may result from a misinterpretation of incoming sensory signals by the cerebral cortex. In order to deal with the overwhelming amount of sensory input, the brain applies filters or schema based on what it expects to find, a process known as hypothesis guided search.5 In the case of phantom vibrations, because the brain is anticipating a call, it misinterprets sensory input according to this preconceived hypothesis. The actual stimulus is unknown, but candidate sensations might include pressure from clothing, muscle contractions, or other sensory stimuli.

Although hallucinations are sometimes pathological, they often occur in normal individuals and are not limited to vibrations. Auditory hallucinations of cell phone ring tones also occur.6 The extremely high prevalence of phantom vibrations encountered in our sample attests to the fact that normal brain mechanisms are at work. Why some individuals experience it while others do not, why it is more common in younger people (or house staff), and why some body locations seem to be more prone than others to developing phantom vibrations remain unanswered questions. It may be that neural plasticity of younger people makes them more susceptible to imagine vibrations. Alternatively, it may be that pages received by medical students and house staff are more likely to require urgent attention than those received by attending physicians. Like new mothers who constantly imagine they hear their baby crying, students and residents check and recheck their pagers.

For those who attempted to stop the phantom vibrations, relocating the device was often successful. Possibly, moving the source of the vibrations interferes with the brain’s creation of a sensory memory for that particular location. Also the sensations, which were associated with frequency of use, seemed to disappear if not reinforced. Refraining from using the device in vibrate mode did not work for everyone, however, and some people felt the device vibrating even when they were not in contact with it.