During the 19th century and early 20th century, American psychiatry shared many intellectual traditions and values with Great Britain and Europe. These include principles derived from the ...Enlightenment concerning the dignity of the individual and the value of careful observation. During the 20th century, however, American psychiatry began to diverge, initially due to a much stronger emphasis on psychoanalytic principles, particularly in comparison with Great Britain. By the 1960s and 1970s, studies such as the US-UK study and the International Pilot Study of Schizophrenia demonstrated that the psychodynamic emphasis had gone too far, leading to diagnostic imprecision and inadequate evaluation of traditional evaluations of signs and symptoms of psychopathology. Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSM-III) was developed in this context, under the leadership of representatives from institutions that had retained the more traditional British-European approaches (eg, Washington University, Iowa). The goal of DSM-III was to create a comprehensive system for diagnosing and evaluating psychiatric patients that would be more reliable, more valid, and more consistent with international approaches. This goal was realized in many respects, but unfortunately it also had many unintended consequences. Although the original creators realized that DSM represented a "best effort" rather than a definitive "ground truth," DSM began to be given total authority in training programs and health care delivery systems. Since the publication of DSM-III in 1980, there has been a steady decline in the teaching of careful clinical evaluation that is targeted to the individual person's problems and social context and that is enriched by a good general knowledge of psychopathology. Students are taught to memorize DSM rather than to learn complexities from the great psychopathologists of the past. By 2005, the decline has become so severe that it could be referred to as "the death of phenomenology in the United States."
For many years the cerebellum has been considered to serve as a coordinator of motor function. Likewise, for many years schizophrenia has been considered to be a disease that primarily affects the ...cerebrum. This review summarizes recent evidence that both these views must be revised in the light of emerging evidence about cerebellar function and the mechanisms of schizophrenia. Evidence indicating that the cerebellum plays a role in higher cortical functions is summarized. Evidence indicating that cerebellar abnormalities occur in schizophrenia is also reviewed. These suggest interesting directions for future research.
Antipsychotic treatment is the first-line treatment option for schizophrenia. Individual studies suggested they can significantly affect brain structure and account for progressive brain changes ...observed during the illness.
To quantitatively examine the effect of antipsychotics as compared to illness related factors on progressive brain changes in schizophrenia.
Electronic databases were searched until April 2012. All magnetic resonance imaging studies reporting progressive brain changes in schizophrenia subjects and antipsychotic exposure were retrieved.
30 longitudinal MRI studies with antipsychotic administration in schizophrenia patients met the inclusion criteria.
Brain volumes before and after antipsychotic exposure, duration of illness, severity of psychotic symptoms as well as demographic, clinical, and methodological variables were extracted from each publication, or obtained directly from its authors.
The overall sample was of 1046 schizophrenia patients and 780 controls for a median duration of follow-up of 72.4 weeks. At baseline, patients showed significant whole brain volume reductions and enlarged lateral ventricle (LV) volumes compared to controls. No baseline volumetric abnormalities were detected in the gray matter volumes (GMV), white matter volumes, cerebrospinal fluid and caudate nucleus. Longitudinally, there were progressive GMV decreases and LV enlargements in patients but not in controls. The GMV decreases were inversely correlated with cumulative exposure to antipsychotic treatments, while no effects were observed for duration of illness or illness severity.
Schizophrenia is characterized by progressive gray matter volume decreases and lateral ventricular volume increases. Some of these neuroanatomical alterations may be associated with antipsychotic treatment.
ObjectiveLongitudinal structural MRI studies have shown that patients with schizophrenia have progressive brain tissue loss after onset. Recurrent relapses are believed to play a role in this loss, ...but the relationship between relapse and structural MRI measures has not been rigorously assessed. The authors analyzed longitudinal data to examine this question.MethodsThe authors studied data from 202 patients drawn from the Iowa Longitudinal Study of first-episode schizophrenia for whom adequate structural MRI data were available (N=659 scans) from scans obtained at regular intervals over an average of 7 years. Because clinical follow-up data were obtained at 6-month intervals, the authors were able to compute measures of relapse number and duration and relate them to structural MRI measures. Because higher treatment intensity has been associated with smaller brain tissue volumes, the authors also examined this countereffect in terms of dose-years.ResultsRelapse duration was related to significant decreases in both general (e.g., total cerebral volume) and regional (e.g., frontal) brain measures. Number of relapses was unrelated to brain measures. Significant effects were also observed for treatment intensity.ConclusionsExtended periods of relapse may have a negative effect on brain integrity in schizophrenia, suggesting the importance of implementing proactive measures that may prevent relapse and improve treatment adherence. By examining the relative balance of effects, that is, relapse duration versus antipsychotic treatment intensity, this study sheds light on a troublesome dilemma that clinicians face. Relapse prevention is important, but it should be sustained using the lowest possible medication dosages that will control symptoms.
Background Schizophrenia has a characteristic onset during adolescence or young adulthood but also tends to persist throughout life. Structural magnetic resonance studies indicate that brain ...abnormalities are present at onset, but longitudinal studies to assess neuroprogression have been limited by small samples and short or infrequent follow-up intervals. Methods The Iowa Longitudinal Study is a prospective study of 542 first-episode patients who have been followed up to 18 years. In this report, we focus on those patients ( n = 202) and control subjects ( n = 125) for whom we have adequate structural magnetic resonance data ( n = 952 scans) to provide a relatively definitive determination of whether progressive brain change occurs over a time interval of up to 15 years after intake. Results A repeated-measures analysis showed significant age-by-group interaction main effects that represent a significant decrease in multiple gray matter regions (total cerebral, frontal, thalamus), multiple white matter regions (total cerebral, frontal, temporal, parietal), and a corresponding increase in cerebrospinal fluid (lateral ventricles and frontal, temporal, and parietal sulci). These changes were most severe during the early years after onset. They occur at severe levels only in a subset of patients. They are correlated with cognitive impairment but only weakly with other clinical measures. Conclusions Progressive brain change occurs in schizophrenia, affects both gray matter and white matter, is most severe during the early stages of the illness, and occurs only in a subset of patients. Measuring severity of progressive brain change offers a promising new avenue for phenotype definition in genetic studies of schizophrenia.
New advances in the understanding of schizophrenia etiology, course, and treatment have increased interest on the part of patients, families, advocates, and professionals in the development of ...consensus-defined standards for clinical status and improvement, including illness remission and recovery. As demonstrated in the area of mood disorders, such standards provide greater clarity around treatment goals, as well as an improved framework for the design and comparison of investigational trials and the subsequent evaluation of the effectiveness of interventions. Unlike the approach to mood disorders, however, the novel application of the concept of standard outcome criteria to schizophrenia must reflect the wide heterogeneity of its long-term course and outcome, as well as the variable effects of different treatments on schizophrenia symptoms. As an initial step in developing operational criteria, an expert working group reviewed available definitions and assessment instruments to provide a conceptual framework for symptomatic, functional, and cognitive domains in schizophrenia as they relate to remission of illness. The first consensus-based operational criteria for symptomatic remission in schizophrenia are based on distinct thresholds for reaching and maintaining improvement, as opposed to change criteria, allowing for alignment with traditional concepts of remission in both psychiatric and nonpsychiatric illness. This innovative approach for standardizing the definition for outcome in schizophrenia will require further examination of its validity and utility, as well as future refinement, particularly in relation to psychosocial and cognitive function and dysfunction. These criteria should facilitate research and support a positive, longer-term approach to studying outcome in patients with schizophrenia.
Brain reward processing mechanisms that underlie complex decision-making are compromised in psychosis. The goal of this research was to advance our understanding of the underlying (1) neural ...mechanisms and (2) discrete neuro-economic/motivational processes that may be altered in complex decision-making in euthymic patients on the psychosis spectrum (PPS). Utilizing a functional magnetic resonance neuroimaging (fmri) paradigm of a well-validated laboratory measure of complex decision-making (Iowa Gambling Task-IGT), the brain activation patterns of a target group of PPS were compared to a demographically matched healthy comparison group (HMC). These two groups were also evaluated on real-life decision outcomes on day of scan. PPS primarily activate the Dorsal Attentional Network (DAN) in real-life decision outcomes and in achieving similar levels of performance on the IGT as the HMC, in-spite of dysregulated dopamine-based brain-reward circuit and salience network fmri activation patterns. However, PPS report more significant negative outcomes of their decision-making in real-life, compared to HMC. The differential engagement of brain networks by PPS on the IGT appear to be moderated by antipsychotic, dopamine antagonist, medication lifetime/daily dose levels. These findings may also be mediated by extent of dysregulation in brain reward circuitry and salience network associated with psychosis severity in the target PPS group. This is also evident in case studies of unmedicated PPS. We conclude by suggesting that the brain may adapt to this dysregulation by co-opting the DAN network, which is implicated in the related function of problem-solving, towards complex decision-making. The extent of utilization of the DAN network in complex decision-making may be moderated by psychosis severity.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
OBJECTIVE: The relationship between cognition and outcome in people with schizophrenia has been established in studies that, for the most part, examined chronic patients and were cross-sectional in ...design. The purpose of this study was to analyze the relationships between neurocognitive variables assessed at illness onset and functional outcome in a longitudinal design. An additional area of interest was whether the severity of negative symptoms would predict outcome independently from neurocognitive variables or whether there would be an overlap in their predictive power. METHOD: The authors administered a comprehensive cognitive battery and clinical assessments to 99 subjects who were in their first episode of illness and analyzed the relationship of cognition and symptom severity at intake with community outcome after an average follow-up period of 7 years. RESULTS: Verbal memory, processing speed and attention, and the severity of negative symptoms at intake were related to subsequent outcome. Global psychosocial functioning was predicted by negative symptoms and attention. Verbal memory was the significant predictor of the degree of impairment in recreational activities. Impairment in relationships was predicted by negative symptoms and memory, whereas attention and negative symptoms were predictive of work performance. There was an overlap in the variance in outcome explained by cognitive variables and negative symptoms. CONCLUSIONS: Verbal memory and processing speed and attention are potential targets for psychosocial interventions to improve outcome. Results from cross-sectional or chronic patient studies do not necessarily correspond to the findings of this prospective first-episode study in which cognition appears to explain less of the variance in outcome.
Brain research on mental illnesses has made substantial advances in recent years, supported by conceptual and technological developments in cognitive neuroscience. Brain-based cognitive models of ...illnesses such as schizophrenia and depression have been tested with a variety of techniques, including the lesion method, tract tracing, neuroimaging, animal modeling, single-cell recording, electrophysiology, neuropsychology, and experimental cognitive psychology. A relatively sophisticated picture is emerging that conceptualizes mental illnesses as disorders of mind arising in the brain. Convergent data using multiple neuroscience techniques indicate that the neural mechanisms of mental illnesses can be understood as dysfunctions in specific neural circuits and that their functions and dysfunctions can be influenced or altered by a variety of cognitive and pharmacological factors.
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