CLINICAL HANDBOOK OF SCHIZOPHRENIA

9. Psychopathology 89lished WHO. The authors of the ICD-10 (WHO, 2003) section on schizophreniaacknowledged that none of the symptoms categorized under schizophrenia could be consideredpathognomic. However, they specified that there was a practical usefulness in dividingthe symptoms into groups based on their importance to diagnosis and patterns ofoccurrence. These include the following symptoms:1. Thought echo, thought insertion or withdrawal, and thought broadcasting.2. Delusions of control, influence, or passivity, clearly referred to body or limbmovements or specific thoughts, actions, or sensations; delusional perception.3. Hallucinatory voices giving a running commentary on the patient’s behavior, ordiscussing the patient among themselves, or other types of hallucinatory voicescoming from some part of the body.4. Persistent delusions of other kinds that are culturally inappropriate and completelyimpossible, such as religious or political identity, or superhuman powersand abilities (e.g., being able to control the weather, or being in communicationwith aliens from another world).5. Persistent hallucinations in any modality, when accompanied by either fleeting orhalf-formed delusions without clear affective content or persistent overvaluedideas, or when occurring every day for weeks or months on end.6. Breaks or insertions into the train of thought, resulting in incoherence or irrelevantspeech, or neologisms.7. Catatonic behavior, such as excitement, posturing, or waxy flexibility, negativism,mutism, and stupor.8. “Negative” symptoms such as marked apathy, paucity of speech, and blunting orincongruity of emotional responses, usually resulting in social withdrawal andlowering of social performance; it must be clear that these are not due to depressionor to neuroleptic medication.9. A significant and consistent change in the overall quality of some aspects of personalbehavior that manifests as loss of interest, aimlessness, idleness, a self-absorbedattitude, and social withdrawal.DIFFERENCES BETWEEN DSM-IV-TR AND ICD-10There are several differences between the latest versions of DSM and ICD diagnostic systemswith respect to symptoms. DSM is more general, whereas ICD is more specific regardingthe types of psychotic symptoms. ICD requires three symptoms, whereas DSMrequires that two of five categories to be present (although if certain Schneiderian symptomsare present, only one category has to be met). ICD requires that symptoms be presentfor only 1 month, whereas DSM requires a duration of illness of 6 months.FUTURE DIRECTIONSWith the increasing influence of the neuroscience in schizophrenia research, a new paradigmshift has occurred regarding the conceptualization of symptom domains in schizophrenia.Each symptom domain is thought to be associated with unique neurocircuitryregulated by distinct neurotransmitters, receptors, and genes. Neuroscience suggests that(1) positive symptoms are influenced by dopaminergic systems involving the striatum andthe nucleus accumbens; (2) affective symptoms involve dopaminergic and serotonergicprojections to the ventromedial cortex; and (3) cognitive symptoms involve dopaminergic