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This is a relatively rare condition, estimated to affect about 1 in 10 people, and is characterised by the experience of not having an ‘inner voice.’ Nothing to do with a conscience, an inner voice is the sound you imagine inside your head when you are consciously thinking. Like, for instance, framing a sentence in your mind before typing it out.
It was earlier assumed that an inner voice was a human universal. But it has emerged that it isn’t. There are grades of anendophasia. Some say that they think in pictures and then translate the pictures into words when they need to say something. Others describe their brain as a well-functioning computer that just does not process thoughts verbally, and that the connection to loudspeaker and microphone is different from other people’s. And those who say that there is something verbal going on inside their heads will typically describe it as words without sound, according to linguist, Johanne Nedergård from the University of Copenhagen, who has studied the condition.
Experiments suggested that participants without an inner voice were significantly worse, than those without the condition, at remembering the words and determining whether a set of words, rhyme. However, anendophasia did not seem to affect cognitive reasoning abilities.
