Schizophrenia often results in chronic disability and poor outcome. The present paper focuses on positive symptoms, and more precisely on hallucinations. With the current scientific and technological advances, mapping of the brain becomes possible, and symptoms such as hallucinations can be better understood. In fact, neurological studies seem to corroborate the fact that numerous brain abnormalities such as enlarged cranial ventricles, especially the third ventricle, and decreased cerebral size tend to correlate with the positive and negative symptoms found in schizophrenia. In fact, imaging studies utilizing blood flow and glucose metabolism indicate that positive symptoms are highly correlated to temporal lobe dysfunction. Thus, current evidence suggests that auditory hallucinations are connected to anatomical structures and pathways related to the language system. In light of the biological substrates of this illness, various promising treatments are reviewed.
Schizophrenia and Hallucinations
Throughout history, there have been beings who claim to hear voices or witness apparitions. In certain cultures, individuals who hear voices or communicate with the â€œotherâ€ world are highly respected. For example, shamans of various indigenous groups enter states of trance in order to receive valuable information from the â€œspiritsâ€ in the form of voices or visual images, and thereby help their people heal from different ailments. Furthermore, in modern societies, individuals often seek guidance from so-called psychics, who claim to communicate with the deceased, or channel teachings from certain entities. In fact, whole cults evolve around such circumstances. Also, some humans seem to be endowed with capacities that challenge all scientific concepts and cultural understanding. Therefore, as a therapist, diagnosing a case of schizophrenia might result in cultural conflict. Thus, new scientific evidence strives at differentiating states of psychosis from religious trances and compiling a cluster of symptoms that are specific to the psychological disorder known as schizophrenia.
According the Surgeon General, the cause of schizophrenia has not been determined. Research indicates that genetic predisposition coupled with major environmental disruption during the developmental stage of the brain is implicated in the development of this disorder. Furthermore, environmental factors can later either exacerbate or ameliorate the expression of a genetic predisposition to developing schizophrenia (http://www.surgeongeneral.gov).
According to the DSM-IV-TR, the essential features of schizophrenia include both positive and negative symptoms. In order to diagnose this disorder, the symptoms must have been experienced for at least one month, with some signs of the disorder persisting for at least six months. Signs and symptoms are associated with serious social or occupational dysfunction and include a range of cognitive and emotional dysfunctions such as perception, inferential thinking, communication, behavioral monitoring, affect, fluency and productivity of thought and speech, volition and drive, and attention. On the one hand, the positive symptoms can manifest as distortions in thought content (delusions), perception (hallucinations), disorganized speech, and disorganized behavior. For example, â€œpatients may believe that other people can hear their thoughts or that the government is monitoring their every actionâ€ (Fletcher & Frith, 2009). On the other hand, negative symptoms include flat affect, diminished productivity of speech (alogia), and inability in initiating goal-directed behavior (avolition). This paper focuses on the positive symptoms, especially the auditory hallucinations.
According to a report of the Surgeon General (http://www.surgeongeneral.gov) patients suffering from schizophrenia exhibit numerous brain abnormalities such as enlarged cranial ventricles, especially the third ventricle, and decreased cerebral size. Furthermore, these brain abnormalities tend to correlate with the positive and negative symptoms found in schizophrenia. In fact, imaging studies utilizing blood flow and glucose metabolism indicate that positive symptoms are highly correlated to temporal lobe dysfunction. Also, excessive levels of dopamine seem to be implicated in schizophrenia.
â€œHallucinations as they typically occur in schizophrenia commonly contain spoken language in the form of words or entire sentences. Their relationship to the language system of human brain is therefore evidentâ€ (StrikÂ & Dierks, 2008). In their fMRIÂ study of hallucinating patients with schizophrenia, StrikÂ and DierksÂ (2008) demonstrated that during auditory hallucinations, the motor speech area, also known as Brocaâ€™s area, and the primary auditory cortex (Heschlâ€™s gyrus) in the language dominant hemisphere were activated. As a result of this co-activation, this abnormal excitatory event is related to the subjective experience of a real acoustic stimulus. Thus, current evidence suggests that auditory hallucinations are connected to anatomical structures and pathways related to the language system. Corroborating these findings, Spencer, Niznikiewicz, Nestor, Shenton, and McCarley (2009) state that there is sufficient evidence implicating the language related areas of the left cerebral hemisphere in auditory hallucinations in schizophrenia. In addition, they also indicate that the left primary auditory cortex (Heschlâ€™s gyrus) is related to auditory hallucinations as well.
According to BoskaÂ (2009), auditory hallucinations are a diagnostic feature of schizophrenia occurring in 60%-70% of people with this disorder. As a result, many studies have focused on the visible changes within the nervous system structure, function and connectivity. Findings demonstrate reduced areas of grey matter in the superior temporal gyrus, including the primary auditory cortex. Furthermore, volume reduction in the dorsolateralÂ prefrontal cortex has also been reported, thus implying that faulty frontotemporal interactions may contribute to involuntary hallucinations. Also, current results in neuroimagingÂ tend to indicate overactivity in the primary and/or secondary auditory cortices in the superior temporal gyrus and altered connectivity with language processing areas in the inferior frontal cortex. Thus, current data seems to corroborate the expectation that hallucinations involve altered activity in the neural circuitry known to be involved in normal audition and language. To this date, the cause of this altered activity remains unknown.
In their study Zhang, Hao, Shi, Mou, Yao, and Chen (2008) confirmed that schizophrenic patients with auditory hallucinations (AVHs) exhibited less cerebral activation in the right superior temporal gyrus as compared with healthy controls. Furthermore, hallucinating patients also demonstrated decreased activation in the areas implicated in voice perception, thus creating difficulty in recognizing external voices. The authors cite the example of a woman with schizophrenia whose auditory hallucinations stopped while she was exposed to loud external speech, thus implying that patients suffering from auditory hallucinations have impairment in the ability to discriminate between their own voice and another personâ€™s voice.
In their study, Fletcher and FrithÂ (2009) speculate that abnormal perceptions are due to a failure to ignore irrelevant stimuli, such as oneâ€™s own thoughts. Thus, patients suffering from such hallucinations are unable to tag these stimuli as self-generated. Physiologically, the ability to distinguish personal thoughts and actions requires a form of self-monitoring dependent on processes such as corollary discharge and efference copy. These processes help other brain structures attenuate responses to the sensory consequences of self-generated actions or speech. Therefore, when such processes are disrupted for unknown reasons, oneâ€™s experiences might not be attenuated and experienced as caused by external forces.
According to the DSM-IV-TR, the first psychotic episode of schizophrenia is usually experienced in the early to mid-20sÂ for men and in the late 20s for women. Incremental and insidious signs and symptoms, such as social withdrawal, loss of interest in school or work, lack of hygiene, strange behavior, and outbursts of anger, are the first indications of a disturbance. At first, family members might assign such behaviors to a â€œdifficultâ€ phase, and it is not until the â€œactiveâ€ phase begins, that schizophrenia is diagnosed. Additionally, the onset of schizophrenia may be characterized by negative symptoms, but with the progression of the illness, more positive symptoms appear. Furthermore, males demonstrate poorer premorbid adjustment, lower educational achievement, evidence of structural brain abnormalities, and a worse outcome. On the other hand, females tend to experience a better outcome and demonstrate less structural brain abnormalities.
Complete remission is unlikely, and the course of the illness can either be stable in some individuals, or worsen in others. In general, positive symptoms are better responsive to treatment and can diminish, but for the majority of patients, negative symptoms persist.
According to research, auditory hallucinations that are not threatening to the individual, but instead are positive and supportive seem to act as barriers to treatment seeking (Jenner, Rutten, Beuckens, Boonstra, & Systema, 2008). When dealing with schizophrenia, it appears that auditory hallucinations are mostly negative. Thus, according to the researchers, the hearing of positive voices is usually experienced among non-psychotic patients, â€œbut the specific characteristics and diagnosis are not significantly associatedâ€ (Jenner et al., 2008). Furthermore, patients who exhibit both types of voices seem to find consolation in the positive and gentle voices and therefore, express a desire to preserve these voices. Jenner et al. (2008) describe the case of a 42-year old woman seeking treatment to help her deal with the imperative and controlling negative voice she was hearing, but reporting also hearing a soft and gentle female voice, which she qualified as supportive. In addition, this gentle female voice reminded her of her appointments and aided in treatment compliance.
To this day, no diagnostic physiological markers have been found in the case of schizophrenia. Therefore, clinicians must apply judgment when compiling the various symptoms reported by the patients. Thus, diagnosis is made on the basis of signs observed and previous history (Fletcher & Frith, 2009). Although drug treatment and cognitive behavioral therapy might help in certain instances, there is no cure for this disorder.
Because of the cognitive impairments associated with schizophrenia, interventions that improve cognitive functions also have the capacity to improve the quality of life. In her review of the various drugs used to treat cognitive impairment in schizophrenia, GalletlyÂ (2009) warns of the biases inherent in industry-sponsored research. Thus, after reviewing the effects and side-effects of antipsychotic drugs, dopaminergic agents, cholinergic agents, acetylcholinesteraseÂ inhibitors, nicotinic receptor agonists, muscarinicÂ agonists, glutamate, and other possible cognitive enhancers, she concludes that none of the drugs available today stand out as effective cognition enhancers in schizophrenia.
In another study, Naeem, Kingdon, and Turkington (2008) recommend using cognitive therapy (CBT) for the treatment of schizophrenia. According to them, there is ample evidence that cognitive therapy is effective in the treatment of psychotic symptoms. Furthermore, they add that insight about oneâ€™s illness is a predictor of good outcome. Thus, good insight increases compliance and motivation. Unfortunately, the authors fail to mention what pharmacological treatments participants were receiving at the time of the intervention. Therefore, results concerning the effectiveness of CBT cannot fully be considered without the knowledge of accompanying treatments. Furthermore, results of this study are also questionable considering the fact that cognitive therapy was administered by nurses instead of clinicians.
A promising new approach to the treatment of schizophrenia, and especially auditory hallucinations, is transcranialÂ magnetic stimulation. As is mentioned above, many patients fail to respond to standard antipsychotic medications, thus, repetitive transcranialÂ magnetic stimulation (rTMS) was developed. TMS is a non-invasive means of stimulating nerve cells in superficial areas of the brain with an electrical current passing through a wire coil placed over the scalp. As a result of this procedure, a magnetic field produces a depolarization of nerve cells resulting in the stimulation or disruption of brain activity (Fitzgerald & Daskalakis, 2008). In accordance with the previous researchers, Tranulis, Sepehri, Galinowski, and StipÂ (2008) also conclude that transcranial magnetic stimulation is highly efficient in reducing hallucinations, but they add that to this day, data is insufficient to conclude that this technique also improves global psychopathology, overall functioning, or quality of life.
Finally, another promising and non-invasive technique to help patients suffering from schizophrenia is electro-acupuncture. According to the oldest text on traditional Chinese medicine, acupuncture has been successful in treating schizophrenia-like diseases and auditory hallucinations (Jing, Gaohua, Ling, Huiling, & Xiaopong, 2009). In their study, Jing et al. (2009) compared two groups of patients experiencing auditory hallucinations. One group received electro-acupuncture while the control group received sham electro-acupuncture. Results indicated a significant improvement in positive symptoms of participants receiving electro-acupuncture. Thus, their findings are consistent with previous trials in demonstrating the beneficial effects of electro-acupuncture in the treatment of auditory hallucinations in patients with schizophrenia.
In light of the above results, there seems to be hope in the use of non-invasive therapies. Techniques such as acupuncture have successfully been used for thousands of years. Considering all the negative side-effects associated with the use of various pharmacological drugs, more research should perhaps be conducted with natural techniques.
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A personal account given by a highly educated woman who hears voices in her head. She discusses the stigma of â€œschizophreniaâ€ , her battle with the voices, despair, and how she finally learned from the voices.