The last great mystery of the mind: meet the people who have unusual – or non-existent – inner voices

Claudia*, a Lichfield sailor in her 30s, is not Italian. She has never been in Italy. She doesn't have any Italian friends or family. She doesn't know why an angry couple from Italy has taken control of her inner voice and are now battling it out in Claudias head while she listens.
Claudia apologetically says that she has no idea from where this came. It is probably offensive to Italians. Claudia says, "I have no idea where this has come from." The Italians will take control if Claudia has to make a major decision in her life.

Claudia states that they passionately disagree with each other. Claudia says it is very useful as I let them do the work so that I don't get stressed. Claudia has not yet given the names of the Italians. They did however help Claudia make a significant life decision. Claudia quit her job as scientist to follow her lifelong dream to sail away to the sea.

Claudia sighs. They chatted non-stop until I gave in my notice. They would be arguing when I woke up. They would argue as I drove to work. It was exhausting. He'd say: It's a stable job! Let her have fun! Claudia went to Greece to work for a flotilla. However, she is now temporarily back in the UK due to Covid. Even though she had to use neurolinguistic programming to calm down the screaming, she is much happier. Claudia is relieved that they are now quieter. They are less loud. They just argue.

Many of us have an inner voice. It is that constant voice that reminds us to be careful, buy shampoo, or otherwise make us look like creeps. Many of us hear this voice as our inner voice, or at least the way we believe we sound. Some people's inner voices aren't just a monologue of reproaches, counsels, and reminds. They may be a grumbling couple from Italy or a quiet interviewer whose hands are folded on their lap. It could be a taste, feeling or sensation, or even a colour. Sometimes, the voice is just silence.

Justin Hopkins describes his mind as a small island surrounded by an endless ocean. Hopkins, 59, works in London for a social enterprise. He doesn't believe he has an inner voice. His brain doesn't have anyone to blame, shame, or criticise. His head is empty. It's just still warm air before a breeze.

Hopkins says there is nothing. Hopkins says that there is nothing there. The inner monologue that fills the engine's brain as it idles isn't there. It has been permanently turned off. He says that he can think of no words when he is alone and relaxed. That is a great feeling. Hopkins can spend an hour thinking about nothing. Hopkins is a natural babysitter.

Why is Hopkins so disconnected from his inner voice? This is a great question, Dr Helene Loevenbruck, a neuroscientist at Grenoble Alpes University's laboratory of psychology & neurocognition. Loevenbruck is among a few neuroscientists who have studied the inner voice. It is formed in a network that includes the inferior parietal and superior frontal gyrus, as well as the superior temporal cortex.

Understanding how thoughts translate into actions is key to understanding how the inner voice functions. Loevenbruck says that every action we take has a predicted outcome in our brains. Let's say you want to fetch water. Your brain not only sends the motor signals to your hand but also generates a sensory prediction about the command. Your brain predicts what the motor command will do before you even pick up the glass. This allows you to correct mistakes before they occur. This system is extremely efficient and it is why humans can perform so many actions without making mistakes.

Human speech is subject to the same principle. Our brain generates a prediction of the speech we will say every time we speak. Loevenbruck says that inner speech works in the same way as overt speech. We make predictions about what we will say, but don't actually send motor commands to our speech muscles. This is our brain's little auditory signal.

Loevenbruck says that we most often hear what she calls inner language. However, not all inner language is the same. She says that inner speech can be expanded or condensed. They may be perceived as abstract representations or sounds of language. Some people describe their inner voice as a radio that is always on. Others may not have any voice or speak in abstract symbols which do not involve language. Loevenbruck cannot explain why people feel differently about the inner voice. We are already at the limits and most slippery branch of human knowledge, neuroscience.

She explained that people who are deaf experience the inner voice visually. Loevenbruck states that although they don't hear the inner voice, they can create inner language through visualizing hand signs or lip movements. According to Dr Giordon Sternk, a Santa Cruz researcher aged 31 years old, it looks almost like hand signing. Stark, who is deaf and uses sign language to communicate with others, is deaf.

Stark's inner voice is nothing more than a pair hands that sign words in his brain. Stark states that the hands aren't often connected to anything. Stark says that every once in a while I see a face. Stark did not always hear his inner voice. He learned sign language only seven years ago. Before that, Stark used oral communication methods. Stark says he heard his inner voice before that. It sounded almost like it was not mine or very clear to me.

Hannah Begbie's brain is home to Jenni Murray, a broadcaster. Murray is not exactly what you would expect, but a fake Murray with the same queasy voice and a scarf draped loosely over her shoulders. Begbie, 44, lives in London and says that her inner voice is a dualist. It's almost as if I am constantly interviewing people. She says that interviewing takes place in a luxurious radio studio. The walls are richly covered in crushed velvet. It has a warmth, and a color to it.

Jenni might ask: When did it finally occur to you to buy those shoes? Begbie answers. And I say: Jenni, that is an interesting question. Before Begbie quit her job, Murray helped her to rehearse in her head her reasons. Begbie says it is a way to organize the chaos in my head. It is strange, she knows. Ive never met Murray, Begbie says. It's absurd, I know.

Mary Worrall, a former librarian, has always felt her inner voice as a TV screen or slide projector that was constantly playing in her attic. Worrall, a 71-year-old woman who lives in Birmingham, explained that the attic can be accessed via a spiral staircase. She says that there is not much sound. She says it's just images, not sound.

Mona*, a Telford-based CEO, describes it as an emotion. It's not obvious, but it doesn't chatter away. Mona must pay attention to it to see it. Mona says that the inner voice doesn't speak to me in English when I go about my day. It's something that lies beneath and behind my actions.

When she's in an emotional deft situation, her voice is louder. Mona works with troubled kids often. Recently, Mona was in a situation in which a teenager was being outspoken and angry. Mona's first instinct was to disagree with the teenager. Monas inner voice began to speak to her in a grey wash. It was clear that the young man was in serious trouble. I felt sadness and despondency and Mona confirmed it.

Many people I have spoken to discovered that their inner voices weren't the norm. Worrall believed that all people had brain attics for years. She laughs. Mona only described the contours her inner voice to her husband over 30 years before our telephone interview. Mona says that you don't always realize your inner voice is different. It's not something you can talk about.

Unknowable, mysterious, and uniquely ours: our inner voices are our secret confidantes and friends. It's a shame that no one else gets to meet them than us. Worrall says that it would be nice to invite someone. It would be great if I could save the attic to a hard drive so that other people could view it.

Rachel Obordo has also contributed reporting. *Some names may have been changed