A survey on the experience of auditory hallucinations, commonly referred to as hearing voices, found that the majority of voice-hearers hear multiple voices with distinct character-like qualities, with many also experiencing physical effects on their bodies.

In other words,voices in people's heads may be more varied and complex than previously thought. Or they are so subjective as to defy science.

Auditory hallucinations are a common feature of many psychiatric disorders, such as psychosis, schizophrenia and bipolar disorder, but are sometimes experienced by people without a diagnosed psychiatric condition. It is estimated by social scientists that five percent of adults may experience auditory hallucinations during their lifetimes. 

The authors say their findings question some of the current assumptions about the nature of hearing voices and suggest there is a greater variation in the way voices are experienced than is typically stated. The scholars behind the analysis say this variation means different types of therapies could be needed for voice-hearers, such as tailored Cognitive Behavioral Therapy (CBT) geared towards distinct voice sub-types or patterns of voice hearing. Current approaches to help with voices include medication, CBT, voice dialogue techniques and other forms of therapy and self-help.

The authors collected answers to open- and close-ended questions through an on-line questionnaire focused on description of experiences from 153 respondents. The majority of respondents had been diagnosed with a psychiatric condition but 26 had no history of mental illness. Participants were free to respond in their own words. The large majority of respondents described hearing multiple voices (81 percent) with characterful qualities (70 percent).

Less than half the participants reported hearing purely auditory voices with 45 percent reporting either thought-like or 'in between' voices with some thought-like and some acoustic qualities. This finding challenges the view that hearing voices is always a perceptual or acoustic phenomenon, and may have implications for studies of what is happening in the brain when people 'hear' voices.

66 percent of people felt bodily sensations while hearing voices, such as feeling hot or tingling sensations in their hands and feet. Voices with effects on the body were more likely to be abusive or violent, and, in some cases, be linked to experiences of trauma.

While fear, anxiety, depression and stress were often associated with voices, 31 percent of participants said they also felt positive emotions. 

Lead author Dr. Angela Woods, from the Centre for Medical Humanities at Durham University, said, "Our findings have the potential to overturn mainstream psychiatric assumptions about the nature of hearing voices. "We call into question the presumed auditory quality of hearing voices and show that there is an unrecognized complexity in the 'character' qualities of some voices.

"It is crucial to study mental health and human experiences such as voice-hearing from a variety of different perspectives to truly find out what people are experiencing, not just what we think they must be experiencing because they have a particular diagnosis. We hope this approach can help inform the development of future clinical interventions." 

Published in Lancet Psychiatry.