Auditory Hallucinations: Exploring the Experience, Meaning, and Neurology of Hearing Voices

Many of us experience a voice inside our heads: an internal monologue narrating our thoughts and perceptions. But for some, these voices appear as if from something outside or beyond the self.

Auditory hallucinations, otherwise known as paracusia, take many forms. Voices are common, but they can also be non-human, such as animal growls, footsteps approaching, or indistinct ambient sounds. Their significance varies widely based on cultural and personal beliefs.

In the global North, auditory hallucinations are typically associated with psychosis. They’re a key characteristic of psychotic disorders, according to Western psychiatry, and a common fate of psychotic protagonists in box office hits, like A Beautiful Mind.

In line with this notion, a scientific article published last year highlighted auditory hallucinations to be “the most common symptom” of schizophrenia. The most frequent being external voices, which are described in the subreddit r/schizophrenia.

“The voices I hear are as real as a real conversation, but sometimes they're muffled or quiet. They are not "in my head" like thoughts, but external, often like they're coming through the walls, like a noisy neighbour or something,” one user writes.

Some people describe the voices as akin to a background hum, with no clear meaning to what’s being said. Others describe the messages as very clear and, often, rather distressing. Persecutory voices are defined as those which criticise, judge, and mock the affected person. Command voices give instructions ranging from benign to serious harm to self and others.

Another Reddit user writes, “For me it starts off slow then it’ll turn into a continuous loop that doesn’t stop. Usually about needing to harm myself, or cut into myself to get something out that has been planted. It’s 75% of the time really demeaning to me and tearing down myself or any rude-ish over the top insults just shredding any self confidence.” 

In a review paper in Nature, the author proposes that critical voices represent an internalised sense of how people feel they are being judged by others. They highlighted that schizophrenia and other psychotic disorders often emerge during adolescence, a period when individuals are shaping their identities, beliefs, and moral values. During this stage, people begin to internalise social expectations, and feeling out of step with these norms can trigger intense shame. The shame manifests as a voice. 

In line with this theory, epidemiological research shows that auditory hallucinations are more prevalent in people who have experienced childhood trauma. The more severe the trauma, the more likely the hallucinations take the form of malicious and negative voices. 

And it's not just psychotic disorders where these voices occur, but rather several demographics, with and without mental health illnesses, are more likely to experience hallucinations of this nature if they’ve faced abuse during childhood. 

However, not all voices are critics. Sometimes they can be completely harmless, at least in a semantic sense, like nonsensical babbling and background chatter. Sometimes they’re positive guiding forces, giving words of encouragement and kindness, and reminding people about useful information. 

A study carried out at the Hospital Clínico Universitario de València investigated positive voices in schizophrenic patients. It found that the most prominent positive voices helped patients feel important; they also amused them and assisted them in conducting studies and professional work. However, they noted that such voices were more strongly associated with “more grandiosity and to worse general functioning.”

Outside of psychiatry, psychologists have proposed that these voices may represent part of the subconscious. Psychoanalyst Carl Jung experienced auditory hallucinations himself and believed that it was his mind revealing suppressed emotions, memories and undeveloped aspects of personality. 

In his book Memories, Dreams and Reflections, Jung writes, “My aim was to show that delusions and hallucinations were not just specific symptoms of mental disease but also had a human meaning.” He encourages those experiencing such hallucinations to explore their potential meaning using imaginary practice.

In a similar vein, the philosopher Justin Garson has argued in his book Madness: A Philosophical Exploration that delusions and auditory hallucinations can serve a purpose, a view he calls madness-as-strategy. In an article published in Aeon, he criticises the standard approach in psychiatry of viewing those who hear voices as having a ‘broken brain’, and instead advocates for the adoption of new meaning-making frameworks. Many people who hear voices resist the dominant psychiatric view as well. Garson writes:

Some within the voice-hearing community contend that hearing voices is merely a different way of processing information about the world – a form of neurodiversity with its own strengths and limits. Some groups, such as the Plural Movement and, to a lesser extent, proponents of Internal Family Systems, hold that voice-hearing is a natural sign of the multiplicity of the soul. Perhaps all of us are more or less ‘multiple’, and voice-hearing is simply one way that different parts of the mind talk to each other.

Jung also believed that dreams were a major gateway to the unconscious mind, including hypnagogic and hypnopompic hallucinations that can occur as people begin to enter or leave dream states.

According to the Cleveland Clinic, between 8% and 34% of these pre- and post-dream hallucinations are auditory. Like with waking auditory hallucinations, they’re more likely to occur if someone is stressed, anxious, sleep-deprived, or has been using certain medications and drugs. Similarly, they take a variety of forms, verbal and non-verbal. Common sounds include abrupt loud noises – like ringing, knocking and explosions – or fragmented, nonsensical speech and music.

One woman who frequently experiences these hypnagogic auditory hallucinations described her experience:

Usually when I’m falling asleep after being really tired or sick I experience an auditory version of when you feel like you’re falling and jerk yourself awake. Other times I hear a faint rhythm like someone is playing music next door, or murmuring, like someone is talking quietly on the other side of the room. Usually it’s either right as I’m drifting off or if I wake up at night and I’m trying to get back to sleep.

Different research groups have tried to explain the neurology underlying hallucinations of the pre- and post-dream state. A major theory is that the mechanisms of rapid eye-movement (REM) sleep, the sleep phase where we have the most vivid dreams, intrude into the waking state.

Specifically, this mechanism could be the activation of neural circuits between the thalamus and the cortex of the brain. These thalamo-cortical circuits are thought to be responsible for creating "internally generated perceptions," which are sensory-like experiences that feel as though they're coming from the outside, but are actually created from within. 

Imaging studies show thalamo-cortical nerve circuits are dysfunctional in people with schizophrenia. Such research implies an overlapping mechanism in the origin of auditory hallucinations related to both psychosis and dream states. 

Imaging studies also show that patients with schizophrenia, and other disorders where auditory hallucinations occur, have damage to a brain region called the paracingulate sulcus. This area is thought to play a role in “reality monitoring,” the capacity to distinguish self-generated information from external information. 

On a broader level, scientists have proposed that hallucinations may result from a disruption to how the brain processes sensory information. According to the Bayesian model of sensory processing, perception is not just based on incoming sensory information. Instead, it involves a combination of external stimuli and our brain's prior expectations about what we anticipate in reality. Scientists have proposed that when this function is disrupted, self-generated expectations start to override what’s sensed from the environment. When it comes to auditory hallucinations, our brain may be expecting to hear noises and voices, and this expectation overrides their actual absence from the environment. 

Though neuroscience holds plausible theories for auditory hallucinations, some people believe their origins go beyond the material realm. The Greek philosopher Socrates allegedly heard a voice throughout his life that warned him not to do certain things. He believed his voice was a divine sign from the Gods, calling it his daimonion. 

In Plato’s Apology 31c, Socrates states, “It is a voice, and whenever it speaks it turns me away from something I am about to do, but it never turns me towards anything. This is what has prevented me from taking part in public affairs, and I think it was quite right to prevent me. Be sure, gentlemen of the jury, I should have died long ago otherwise.”

The relationship between divine communication and auditory hallucinations is complex. Religious delusions are well recognised as a symptom of psychosis. At the same time, many prominent historical figures have described receiving guidance or messages from a higher power, including Martin Luther King Jr., Joan of Arc, Mahatma Gandhi, and Florence Nightingale. None of them is known for having a psychotic disorder.

Outside mainstream religion, many traditional societies communicate with spirits, hearing their voice in a similar manner to auditory hallucinations. Traditional healers of South Africa, or Sangomas, are often called to their work through messaging from their ancestors – the voices of the spirits of the deceased. Healers in animistic societies, like the Shipibo people in the Amazonian Peru, communicate with spirits of the natural world, using the wisdom of plants to identify and heal problems. However, they may not hear its voice in the same way people hear auditory hallucinations. Instead, there may be some kind of energetic, telepathic transference of information.  

Many people who use psychedelics, particularly naturally occurring plants and fungi, also describe communicating with the spirit or energy of such substances. Some people directly hear a voice, others sense this voice in a more abstract way.

For instance, one blog writer on Medium recounted meeting the spirit of salvia and being “hit with words” with a physical as opposed to an auditory sensation. “The salvia hit me with the words over and over,” they write. “It was both physically and emotionally painful.”

A Reddit user described communicating with the spirit of ayahuasca, who, this time, did have an auditory voice and appeared to be much more gentle. They write, “She comes to me as a soft, comforting female voice when I am having trouble… During rough times since, she has just let me know that she is there because of a whisper or just a feeling of calm overcoming me.”

More tangible auditory hallucinations on psychedelics include mechanical noises, like electrical whines, buzzing, and humming. These tend to be more prevalent with dissociative psychedelics like ketamine and nitrous oxide. People can think they’re hearing fragments of a familiar song, or the whisper of their name, which could be an effect caused by changes in the memory circuits. Auditory hallucinations on psychedelics are also synaesthetic. Sound waves may be visualised as colours or sensed as ripple-like motions moving through the body.

The psychedelic space raises questions about hallucinations. These substances are often synonymous with the term hallucinogens. Yet, some psychedelic users claim the experience doesn’t feel like a departure from reality, but rather a different lens onto it. The world appears less filtered, but not necessarily more fabricated. 

Psychedelics alter the neurological processes by which information is received. However, we can’t for certain say this means of viewing reality is any more or less correct than a non-altered state of consciousness; it’s just simply less coherent to a consensus view. Animals view reality differently from humans, with different structures to their sense organs and different neurological processing systems. Which species gets to ascertain that their worldview is the “correct” one?

In this vein, when we think about auditory hallucinations in psychosis, can we indefinitely say that these voices are delusional? Especially given that some cultures believe that spirits and ancestors really do communicate as a voice inside our head. Moreover, even if such voices are internally generated, our worldview is already distorted by expectations layering onto our sensory experience. So what makes this any more hallucinogenic than the filtered version of reality which we all experience anyway?

Nonetheless, though we can question the nature of auditory hallucinations, that shouldn’t diminish their impact. For some, they can be extremely devastating, cruel, intrusive, and disruptive to day-to-day life. However, when it comes to treating voices in mental health disorders, rather than attempting to simply extinguish these sounds, perhaps it's more important to first try to understand and view them from a holistic perspective.

Martha is one of our community bloggers here at Chemical Collective. If you’re interested in joining our blogging team and getting paid to write about subjects you’re passionate about, please reach out to Sam via email at [email protected]