Phantom vibrations: An understudied marker of clinical risk for psychosis

Early identification of psychosis risk may lead to improved outcomes for those who go on to develop psychotic disorders. Despite significant advances in this domain, there remains a need for novel and valid markers of risk. In the present manuscript, we report on a novel candidate indicator of risk: phantom phone vibrations.

We administered a phantom vibrations questionnaire to 83 clinical high-risk individuals (CHR) and 76 healthy controls. The primary dependent variables of interest were lifetime occurrence, severity, and frequency of phantom vibrations. Convergent validity was assessed via the Launay Slade Hallucinations Scale (LSHS). In a subset of participants, we also estimated relationships between North American Prodrome Longitudinal Study (NAPLS) risk scores and phantom vibrations.

We found that the odds of experiencing phantom cell phone vibrations were 3 times higher for CHR compared to controls (b = 1.11, p = 0.003, OR = 3.03, 95% CI [1.48,6.51]). Furthermore, CHR reported greater frequency (b = 1.07, p = 0.001, OR = 2.92, 95% CI [1.52,5.69]) and bothersomeness of the phantom vibrations (b = 1.48, p < 0.001, OR = 4.39, 95% CI [2.09,9.62]). Greater severity of self-reported hallucinations (LSHS) and greater NAPLS risk scores were also associated with phantom vibration experiences.

Our results suggest that phantom cell phone vibrations are an understudied marker of clinical risk for psychosis. Future work should assess neural mechanisms and longitudinal predictive utility of these experiences.