Good hearing could mean you suffer from schizophrenia or bipolar disorder

People who can make out a conversation in a crowded pub are more likely to hear voices in their heads and suffer mental health problems like schizophrenia or bipolar disorder, a study suggests.

Researchers found they had a three-in-four chance of being able to make meaning of garbled sounds compared to half of the rest of us.

A group of people who suffer from internal imaginary sounds were asked to make sense of a computer-distorted speech, alongside others who have no history of hallucinations.

They were told to listen out for sine waves, “alien-like” noises which can normally be understood only if a hearer is told to pick out certain words.

A total of three-quarters (75 per cent) of the group who hear voices in their heads could make out the sentence amid the noise compared to nearly half (47 per cent) for the other group.

They could also do it faster than their opposite numbers. And MRI scans also showed their brains automatically responded to the sine waves with language, but not the meaningless waves.

The researchers, from both the University College London and Durham University, hope their results will one day help treat some mental health problems.

The test was performed on a group of 34 people, with half having a history of hearing voices compared to half who did not, the study published in the journal Brain, revealed.

Dr Ben Alderson-Day, a research fellow on the project, said the study “suggests that the brains of people who hear voices are particularly tuned to meaning in sounds, and shows how unusual experiences might be influenced by people's individual perceptual and cognitive processes."

Up to 15 per cent of the population hear voices when no one is speaking, although only a fraction of these suffer to a clinically problematic extent, such as diagnoses of schizophrenia or bipolar disorder.

The Research was led by Durham University Hearing the Voice project, a unit devoted to building an understanding of auditory verbal hallucinations.

The study also involved researchers from University of Porto in Portugal, University of Westminster and University of Oxford.