Auditory hallucinations: what is it, symptoms, causes, treatment, prognosis

What are auditory hallucinations?

Auditory hallucinations Is sensory perception of sounds without external stimulus. This symptom is especially associated with, but not specific to, schizophrenia and related psychotic disorders. Auditory hallucinations are one of the main symptoms of psychosis. Non-psychotic disorders associated with auditory hallucinations are known to include mood disorders associated with trauma, psychoactive substances, neurological disorders, personality disorders, as well as their appearance in "healthy" of people. It is important to recognize the disorder associated with the symptom of auditory hallucinations in order to address the underlying cause. These sounds can be disturbing, especially if they are voices and they threaten, humiliate, command or harass, affecting a person's social and professional functioning.

Causes and risk factors

Auditory hallucinations can accompany various disorders. First, auditory hallucinations occur in severe mental disorders that include schizophrenia and other psychotic disorders, affective disorders such as bipolar (manic, mixed, depressive), unipolar depression, personality disorder, post-traumatic stress disorder (PTSD) anorexia, bulimia nervosa. Second, hallucinations can be observed in substance use disorders such as intoxication with stimulants, hallucinogenic drugs, cannabis and withdrawal from substances such as alcohol. Another important etiology is drug-induced psychosis. In particular, auditory hallucinations have been reported as side effects of drugs for attention deficit hyperkinetic disorder, antimalarial and antiparkinsonian drugs.

Fourth, diseases that damage peripheral sensory pathways such as acquired deafness; endocrine metabolic diseases such as thyroid dysfunction and nutritional deficiencies such as vitamin D and B12can manifest as auditory hallucinations. Chromosomal disorders such as Prader-Willi syndrome, autoimmune diseases, and acquired immunodeficiencies such as HIV /AIDSare other causes of auditory hallucinations. Sleep disorders such as narcolepsy, neurological conditions such as tinnitus (noise in ears), brain tumors, traumatic brain injury, epilepsy, especially temporal lobe epilepsy, viral encephalitis, delirium and cardiovascular events that involve areas of the brainstem or areas of the temporal, temporoparietal, or occipital tract should also be considered in differentiation. Neurodegenerative conditions such as Parkinson's disease and dementia with Lewy bodies can cause auditory hallucinations. Finally, hallucinations can occur temporarily under conditions of extreme physiological and psychological stress, such as dissociative personality disorder, fatigue, and bereavement.

Epidemiology

The estimated prevalence of auditory hallucinations in the general population ranges from 5% to 28%. Auditory hallucinations are most common in psychotic patients. They are common in 75% of patients with schizophrenia, 20-50% of patients with bipolar disorder, 10% of people with major psychotic depression and 40% of patients with PTSD.

It was noted that in children and adolescents, the prevalence is 9% and ranges from 5 to 16%, respectively. In children, this is most often seen in combination with conduct disorder, migraine and anxiety. The rate of cessation of auditory hallucinations in adolescence ranges from 3 to 40% each year

Pathophysiology

The pathophysiology of auditory hallucinations has been explained using proposed hypotheses at various levels, including cultural, clinical, cognitive, cellular, cerebral, and molecular levels.

MRI results showed spontaneous activation of the auditory network, which is activation mainly in the left superior temporal gyrus, which further extends to the superior temporal sulcus and areas of classical perception speech. Therefore, this suggests that the pattern of activation in a person without hallucinations and in a person with hallucinations without an external sound source is the same.

Most studies suggest the activation of the frontotemporal-parietal network in auditory hallucinations, however, studies are inconclusive regarding the strength and direction of cortical connections.

A neurocognitive model, called the VOICE model, was presented, explaining auditory hallucinations due to bottom-up hyperexcitation of the system. localized in the auditory-perceptual network in the temporal lobe, and hypo-excitation of the system from top to bottom to the network of executive attention, localized in the area frontal lobes. Auditory hallucinations are considered to be the result of hyperexcitation of the ascending system, so that neurons in this area spontaneously fire in the absence of a triggering external stimulus, and hypoexcitation of the descending system, thus, attention is not adjusted accordingly to the external event, and internal events, respectively, are not suppressed.

Some evidence suggests thalamus-amygdala pathways are activated, thereby processing emotional responses to auditory hallucinations, which is further supported by another study showing abnormalities in the ratio of choline to N-acetyl aspirate in thalamus.

At the neurochemical level, the most frequently discussed hypothesis is the blockade of the dopamine D2 and serotonin 5HT2a receptors. Neuroimaging studies have demonstrated an increased occupancy of the D2 receptor in the striatal system and the occupancy of the 5HT2a receptor in the caudate nucleus. Magnetic resonance spectroscopy studies suggest an indirect role for glutamate and glutamine in auditory hallucinations

Diagnostics

- History and physics.

Auditory hallucinatory experiences are psychopathological endpoints. Disturbances of consciousness may occur earlier in the course, including thought blocking, thought pressure, obsessive perseveration, and an inability to distinguish between thoughts and perceptions.

In the later prodromal stages, internal speech becomes more objective and perceived from the outside.

It is important to differentiate clinical from non-clinical auditory hallucinations.

Clinical auditory hallucinations:

1. Have more linguistic ability with limited vocabulary.
2. Cause a more emotional response.
3. More frequent hallucinations are associated with the formation of illusions.
4. Contain more negative than positive.
5. Lasts longer.
6. They consist of voices that can slowly increase or gradually subside, and there is a desire to answer these voices out loud.
7. Patients believe that these are voices coming from the outside.
8. Interfere with activity and cognitive function.

- Analyzes.

Auditory hallucination analyzes begin with interviews. The interview consists of a general psychiatric interview that includes the development of symptoms prior to the current episode, trigger factors, psychiatric systems analysis, past psychiatric diagnosis and treatment, history of substance use with any recent use, family history of possible mental illness, social history, including a history of trauma (physical, mental or sexual abuse). It is important to remember that the patient's history can be confirmed by accompanying information whenever there is suspicion of a distorted patient's reality.

Second, a detailed medical history should be obtained, including current and past medical diagnoses, currently used medications, including over-the-counter and herbal medications.

The mental status examination will focus on appearance, behavior, thought content, thought process, insight and judgment, in addition to speech, mood, and affect. Describing auditory hallucinations in terms of location, tone, number of voices heard will help distinguish them from preclinical auditory hallucinations.

Finally, a laboratory dataset for determining the cause of auditory hallucinations caused by other non-psychiatric conditions may include, but is not limited to:

1. Urine toxicology.
2. Complete blood count with differential.
3. Vitamin B12 and D levels.
4. Kidney function test.
5. Whey electrolytes.
6. Liver function test.
7. Alcohol in the blood.
8. Computed tomography (CT) or magnetic resonance imaging (MRI) should be considered if organic brain abnormalities are considered in the differential diagnosis.
9. EEG for convulsive disorder.

Treatment

- Pharmacotherapy.

1. The mainstay of pharmacological treatment for auditory hallucinations is the use of antipsychotics. Although they have limited individual clinical efficacy, they make auditory hallucinations bearable. Sometimes it is possible to stop hallucinations with one antipsychotic, and sometimes a second antipsychotic is required in combination with the elimination of auditory hallucinations and other symptoms of psychosis.
2. Clozapine has been shown to be effective in 30-60% of patients with intractable auditory hallucinations. Clozapine does not always completely stop hallucinations, but it significantly reduces them and helps to cope with them in a number of patients.
3. Treatment of schizophrenic patients with two atypical antipsychotics for 4–6 weeks with no clinical response indicates treatment-resistant schizophrenia. Auditory hallucinations may persist in these patients.
4. These patients are advised to use one of the following antipsychotics if they have not tried it before: clozapine 300 to 900 mg / day, risperidone 4 to 6 mg / day, olanzapine 10 to 20 mg / day, quetiapine 300 to 600 mg / day, or aripiprazole 15 to 30 mg / day.
5. Mood enhancers can help people cope better with auditory hallucinations.

- Psychotherapy.

Cognitive Behavioral Therapy (CBT).

1. CBT focuses on emotional and behavioral changes, teaches how to change the experience of auditory hallucinations and teaches a sense of control over them to improve the overall functioning of the person.
2. CBT uses Socratic interviewing rather than confrontation.
3. CBT ideas are at the core of reality testing and behavioral experimentation.
4. CBT can be provided in an individual or group format with additional self-help resources.

Other treatment approaches include TPE (acceptance and responsibility therapy), integrative treatment, hallucination-focused, relationship therapy, distraction and group techniques self help.

- New methods of treatment.

Several studies have shown efficacy in reducing auditory hallucinations with transcranial magnetic stimulation, but there is no conclusive evidence.

Forecast

The symptom of auditory hallucinations in schizophrenia is considered a poor prognostic factor: 50% of patients, taking antipsychotics, achieve complete remission, 25% sometimes hear voices and 25% do not respond treatment.

Other adverse prognostic factors that exacerbate the poor response to treatment include early age at onset, male gender, and multiple hospital admissions.

Complications

Auditory hallucinations can put a person at immediate risk of harming themselves, or may be at risk of harming others if the voices are commanding or derogatory.

People may lack discernment and judgment and may have to be forcibly hospitalized. Care must be taken to build trust and respect in patients in order to maintain regular follow-up even after hospital discharge, given the significant likelihood of relapse due to non-adherence to medication, and appointments.

Moreover, medications have their own short and long term side effects, which include extrapyramidal symptoms noted with antipsychotics, such as dystonia, tremor, tardive dyskinesia, parkinsonism and metabolic syndrome.