An auditory hallucination, or paracusia, is a form of hallucination that involves perceiving sounds without auditory stimulus. Auditory hallucinations need to be distinguished from endaural phenomena in which sounds are heard without any external acoustic stimulation but arise from disorders of the ear or auditory system.
A common form of auditory hallucination involves hearing one or more talking voices. This may be associated with psychotic disorders such as schizophrenia or mania, and holds special significance in diagnosing these conditions. However, individuals may hear voices without suffering from diagnosable mental illness.
There are three main categories into which the hearing of talking voices can often fall: a person hearing a voice speak one’s thoughts, a person hearing one or more voices arguing, or a person hearing a voice narrating his/her own actions. These three categories do not account for all types of auditory hallucinations.
Other types of auditory hallucination include exploding head syndrome and musical ear syndrome. In the latter, people will hear music playing in their mind, usually songs they are familiar with. Reports have also mentioned that it is also possible to get musical hallucinations from listening to music for long periods of time. This can be caused by: lesions on the brain stem (often resulting from a stroke); also, sleep disorders such as narcolepsy, tumors, encephalitis, or abscesses. Other reasons include hearing loss and epileptic activity.
Auditory Hallucination Case Study Examples
Robert Schumann, a famous music composer, spent the end of his life experiencing auditory hallucinations. Schumann’s diaries state that he suffered perpetually from imagining that he had the note A5 sounding in his ears. The musical hallucinations became increasingly complex.
One night he claimed to have been visited by the ghost of Schubert and wrote down the music that he was hearing. Thereafter, he began making claims that he could hear an angelic choir singing to him. As his condition worsened, the angelic voices transmogrified into demonic voices.
Joan of Arc claimed to hear the voices of Saints who were the force that guided her and was resolved to obey these messages as she believed they were sent directly from God. She first began hearing voices when she was thirteen and soon after had visions of St. Michael, St. Catherine and St. Margaret.
The onset of delusional thinking is most often described as being gradual and insidious. Patients described an interest in psychic phenomena progressing to increasingly unusual preoccupations and then to bizarre beliefs “in which I believed wholeheartedly”.
One author wrote of their hallucinations:
“they deceive, derange and force me into a world of crippling paranoia”. In many cases, the delusional beliefs could be seen as fairly rational explanations for abnormal experiences: “I increasingly heard voices (which I’d always call ‘loud thoughts’)… I concluded that other people were putting these loud thoughts into my head”.
Some cases have been described as an “auditory ransom note”.
Possible Causes of Auditory Hallucinations
The premier cause of auditory hallucinations in the case of psychotic patients is schizophrenia. In those cases, patients show a consistent increase in activity of the thalamic and strietal subcortical nuclei, hypothalamus, and paralimbic regions; confirmed via PET scan and fMRI.
Other research shows an enlargement of temporal white matter, frontal gray matter, and temporal gray matter volumes (those areas crucial to both inner and outer speech) when compared to control patients. This implies both functional and structural abnormalities in the brain can induce auditory hallucinations, both of which may have a genetic component.
Mood disorders have also been known to cause auditory hallucinations, but tend to be milder than their psychosis induced counterpart. Auditory hallucinations are a relatively common sequelae of Major Neurocognitive Disorders (formerly dementia) such as Alzheimer’s disease.
Auditory hallucinations have been known to manifest as a result of intense stress, sleep deprivation, and drug use. Genetic correlation has been identified with auditory hallucinations, but most work with non-psychotic causes of auditory hallucinations is still ongoing.
High caffeine consumption has been linked to an increase in the likelihood of experiencing auditory hallucinations. A study conducted by the La Trobe University School of Psychological Sciences revealed that as few as five cups of coffee a day could trigger the phenomenon.
The primary means of treating auditory hallucinations is antipsychotic medications which affect dopamine metabolism. If the primary diagnosis is a mood disorder (with psychotic features), adjunctive medications are often used (e.g., antidepressants or mood stabilizers). These medical approaches may allow the person to function normally but are not a cure as they do not eradicate the underlying thought disorder.
Cognitive-Behavioral Therapy has been shown to help decrease the frequency and distressfulness of auditory hallucinations, particularly when other psychotic symptoms were presenting.
Enhanced Supportive Therapy has been shown to reduce the frequency of auditory hallucinations, the violent resistance the patient displayed towards said hallucinations, and an overall decrease in the perceived malignancy of the hallucinations. Other cognitive and behavioral therapies have been used with mixed success.
In recent years, repetitive transcranial magnetic stimulation (rTMS) has been studied as a biological method of treatment for auditory hallucinations. rTMS plays a role in altering neural activity over language cortical regions. Studies have shown that when rTMS is used as an adjunct to antipsychotic medication in treatment-resistant cases, the frequency and severity of auditory hallucinations can be reduced.
Another source of non-conventional techniques to cope with the voices are provided by the research and findings of the Hearing Voices Movement.
There is on-going research that supports the prevalence of auditory hallucinations, with a lack of other conventional psychotic symptoms (such as delusions, or paranoia), particularly in pre-pubertal children. These studies indicate a remarkably high percentage of children (up to 14% of the population sampled) experienced sounds or voices without any external cause, though it should also be noted that “sounds” are not considered by psychiatrists to be examples of auditory hallucinations.
Differentating actual auditory hallucinations from “sounds” or a normal internal dialogue is important since the latter phenomena are not indicative of mental illness.
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