AB - The origins of schizophrenia have eluded clinicians and researchers since Kraepelin and Bleuler began documenting their findings. However, large clinical research efforts in recent decades have identified numerous genetic and environmental risk factors for schizophrenia. The combined data strongly support the neurodevelopmental hypothesis of schizophrenia and underscore the importance of the common converging effects of diverse insults. In this review, we discuss the evidence that genetic and environmental risk factors that predispose to schizophrenia disrupt the development and normal functioning of the GABAergic system.
In the DSM-5, depressive disorders are listed independently from the bipolar-related disorders because of the absence of manic or hypomanic symptoms and “the presence of sad, empty, or irritable mood, accompanied by somatic and cognitive changes that significantly affect the individual’s capacity to function” (APA, 2013, p. 155). However, the depressive disorders are a neighboring chapter to bipolar-related disorders because “of symptomatology, family history and genetics” (APA, 2013, p. 123). For example, major depressive episodes commonly precede manic episodes in bipolar I disorder, and a current or past major depressive episode is required for a diagnosis of bipolar II disorder. Cyclothymic disorder contains numerous depressive symptoms that do not meet the criteria for a major depressive episode. Included in the depressive disorders chapter in the DSM-5 are:
Environmental models of schizophrenia
Also new to the DSM-5 are descriptive and course specifiers applicable after 12 months to all schizophrenia spectrum and other psychotic disorders except for brief psychotic disorder (subsides after one month) and schizophreniform disorder (replaced with schizophrenia disorder after a duration of six months). These specifiers include the following:
Neurodevelopmental hypothesis of schizophrenia. - Medscape
In diagnosing schizophrenia, clinicians will notice an important conceptual change from DSM-IV-TR. An individual can no longer meet Criterion A for psychosis with a single bizarre delusion, but must have a minimum of two symptoms – one of which must be one of the core psychotic symptoms of “delusions, hallucinations or disorganized thinking.”
The subtype or category of schizophrenia that can be ..
For post-traumatic stress disorder (PTSD), there are now four symptom clusters in the DSM-5 (as opposed to three in DSM-IV-TR): re-experiencing, avoidance, persistent negative alterations in mood and cognition, and arousal. In the DSM-5, PTSD is now developmentally sensitive. Diagnostic thresholds have been lowered and criteria modified for children six and younger. Criteria for both acute stress disorder and PTSD are now more explicit concerning how the distressing or traumatic event was experienced: directly, witnessed or indirectly. The DSM-5 work group members believe the changes to the PTSD criteria are unlikely to affect epidemiology of the disorder, but if there is any effect, it will be to lower the prevalence slightly.
Neurodevelopmental hypothesis of schizophrenia. - …
The DSM-5 retains all 10 DSM-IV-TR personality disorders, including Cluster A odd and eccentric, Cluster B dramatic and erratic, and Cluster C anxious and avoidant disorders with no changes to diagnostic criteria. The DSM-5 uses the DSM-IV-TR description of a General Personality Disorder that requires an enduring pattern of inner experience and behavior that deviates markedly from the expectations of the individual’s culture - with two symptoms minimum manifest in cognition, affectivity, interpersonal relationships, or impulsivity.