Friday, 17 October 2008

Auditory Hallucinations, Psychosis & Subjective Reality

  • Psychosis literally means abnormal condition of the mind, and is a generic psychiatric term for a mental state often described as involving a "loss of contact with reality".
  • People suffering from psychosis are said to be psychotic.
  • People experiencing psychosis may report hallucinations or delusional beliefs.

One important and puzzling feature of psychosis is usually an accompanying lack of insight into the unusual, strange, or bizarre nature of the person's experience or behaviour.

(Carpenter, William, Strauss & Bartko - 1973)

Hallucinations are essentially defined as sensory perception in the absence of external stimuli, i.e. perceptions in a conscious and awake state in the absence of external stimuli AND which have qualities of real perception, in that they are vivid, substantial, and located in external objective space.

These definitions distinguish hallucinations from the related phenomena of:

  • Dreaming, which does not involve consciousness;
  • Illusion, which involves distorted or misinterpreted real perception;
  • Imagery, which does not mimic real perception and is under voluntary control;

Hallucinations also differ from "delusional perceptions" in which a correctly sensed and interpreted genuine perception is given some additional and usually bizarre significance. (Hallucinations may occur in any of the five senses and take on almost any form).

Auditory hallucinations

  • Hallucinated voices may talk about, or to the person, and may involve several speakers with distinct personas.
  • Auditory hallucinations tend to be particularly distressing when they are derogatory, commanding or preoccupying.
  • Auditory hallucinations, and in particular the hearing of a voice as well as being a common and often prominent feature of psychosis are additionally thought of as particularly characteristic of people suffering from schizophrenia.

Schizophrenia is a group of psychotic disorders characterized by disturbances in perception, affect, behaviour and communication lasting longer than 6 months. Symptoms are often described in terms of positive and negative with positive symptoms including delusions, auditory hallucinations, and thought disorder. These are typically regarded as manifestations of psychosis and for obvious reasons it is difficult for a person to tell the difference between real and unreal experiences and even in the case of an acute psychosis people may be completely unaware that their vivid hallucinations and delusions are in any way "unrealistic".

“If you talk to God, you are praying.
If God talks to you, you have schizophrenia…..”

(Psychiatrist & Professor of Psychiatry, Thomas S. Szasz)

Normal subjects also report auditory hallucinations to a surprising extent and many studies have shown that hallucinatory experiences take place worldwide. One study from as early as 1894 in a report on the census of hallucinations (Proceedings of the Society for Psychical Research) reported that approximately 10% of the population experienced hallucinations.
  • Bentall and Slade conducted a study in 1985 (Reliability of a scale measuring disposition towards hallucination: a brief report ) and reported that as many as 15.4% of a population of 150 male students were prepared to endorse the statement ‘In the past I have had the experience of hearing a person's voice and then found that no one was there'.

  • Green and McCreery (Apparitions) found that 14% of their 1800 self-selected subjects reported a purely auditory hallucination, and of these nearly half involved the hearing of articulate or inarticulate human speech sounds.

  • Posey and Losch in their 1983 paper, “Imagination, Cognition and Personality” (Auditory hallucinations of hearing voices in 375 normal subjects) estimated that 10% of their population of 375 American college students had had this type of experience and temed it as: “Hearing a comforting or advising voice that is not perceived as being one's own thoughts.”

  • A four year survey of over 13,000 people (Prevalence of hallucinations and their pathological associations in the general population. Psychiatry Research) between 1996-1999 reported a much higher figure, the results which were published in 2000 and revealed that a staggering 39% of people reporting hallucinatory experiences, 27% of which were daytime hallucinations, mostly outside the context of illness or drug use.

Although many people not suffering from a detectable, noticeable or diagnosable mental illness can hear voices as well and there are several support/advocacy organizations and charities geared towards people who hallucinate voices, but do not otherwise show signs of mental illness or impairment. As shown above, research has shown that the majority of people who hear voices are not in need of psychiatric help. There are various explanations for the experience of hearing voices which have been shown to empower voice hearers, enabling them to live with the experience in a positive way and, “The Hearing Voices Movement” was created to support voice hearers, regardless of whether they are considered to have a mental illness or not.

The following was originally posted by Andrea Thompson at 15 September 2006.

Hearing Voices: Some People Like It

For some people, hearing voices in their heads is a positive experience, not a sign of mental illness or cause for distress. Researchers at the University of Manchester are aiming to find out why. Traditionally these auditory hallucinations, as psychologists call them, are associated with mental illness. They can be a symptom of schizophrenia, bipolar disorder and sometimes depression.

But studies by Dutch researchers that began in the 1990s found that some healthy people also regularly hear voices. The scientists ran a program on Dutch television asking for volunteers who heard voices, and they got a surprising response. Many of the people who contacted them did not find the voices disruptive and had never felt the need to consult mental health services. Some even said they found the experience to be positive or inspirational.

The resulting studies found that more people might hear voices than psychologists had thought, perhaps around 4 percent of the population. Aylish Campbell, a psychologist at the University of Manchester , is hoping to expand on the Dutch study by investigating why peoples' reactions to hearing voices vary so widely. Campbell has just begun looking for study participants in Britain . Campbell and her colleagues suspect the variation could be caused by different life experiences. Childhood traumas, beliefs that other people are untrustworthy or dangerous, and feelings of vulnerability might react with fear to cause people to hear voices.

The experience might be enjoyed by people who have positive outlooks, Campbell thinks anyone can hear voices, particularly when stressed. For example, those who are grieving over the recent loss of a loved one might hear that person's voice.

"We're looking for people who hear voices who have a range of experiences…..It might just be a normal human experience…..People are susceptible to different degrees…..If we can understand a bit more about the factors, we might be able to use that knowledge to help people who do find it distressing," said Campbell.

Campbell hopes that learning what triggers different reactions could help develop new psychological therapies to help people—at least those who don't like the phenomenon—to cope with the voices.

Source: LiveScience – Andrea Thompson (15 September 2006)

Auditory Hallucinations:
A comparison between patients and nonpatients.

Honig A, Romme MA, Ensink BJ, Escher SD, Pennings MH, deVries MW. (Department of Psychiatry and Neuropsychology, Maastricht University, Academic Hospital Maastricht, The Netherlands).

The form and the content of chronic auditory hallucinations were compared in three cohorts, namely patients with schizophrenia, patients with a dissociative disorder, and nonpatient voice-hearers. The form of the hallucinatory experiences was not significantly different between the three groups. The subjects in the nonpatient group, unlike those in the patient groups, perceived their voices as predominantly positive: they were not alarmed or upset by their voices and felt in control of the experience. In most patients, the onset of auditory hallucinations was preceded by either a traumatic event or an event that activated the memory of earlier trauma. The significance of this study is that it presents evidence that the form of the hallucinations experienced by both patient and nonpatient groups is similar, irrespective of diagnosis. Differences between groups were predominantly related to the content, emotional quality, and locus of control of the voices. In this study the disability incurred by hearing voices is associated with (the reactivation of) previous trauma and abuse.

Source: National Center for Biotechnology Information.

Sources/Further Reading

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