Background
Bipolar disorder I (BD-I) is defined by episodes of mania, depression and euthymic states. These episodes are among other symptoms characterized by altered reward processing and negative symptoms (NS), in particular apathy. However, the neural correlates of these deficits are not well understood.
Methods
We first assessed the severity of NS in 25 euthymic BD-I patients compared with 25 healthy controls (HC) and 27 patients with schizophrenia (SZ). Then, we investigated ventral (VS) and dorsal striatal (DS) activation during reward anticipation in a Monetary Incentive Delayed Task and its association with NS.
Results
In BD-I patients NS were clearly present and the severity of apathy was comparable to SZ patients. Apathy scores in the BD-I group but not in the SZ group correlated with sub-syndromal depression scores. At the neural level, we found significant VS and DS activation in BD-I patients and no group differences with HC or SZ patients. In contrast to patients with SZ, apathy did not correlate with striatal activation during reward anticipation. Explorative whole-brain analyses revealed reduced extra-striatal activation in BD-I patients compared with HC and an association between reduced activation of the inferior frontal gyrus and apathy.
Conclusion
This study found that in BD-I patients apathy is present to an extent comparable to SZ, but is more strongly related to sub-syndromal depressive symptoms. The findings support the view of different pathophysiological mechanisms underlying apathy in the two disorders and suggest that extra-striatal dysfunction may contribute to impaired reward processing and apathy in BD-I.
Last. Celso Arango(Complutense University of Madrid)H-Index: 58
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Summary Negative symptoms of schizophrenia are associated with poor functional outcome and place a substantial burden on people with this disorder, their families, and health-care systems. We summarise the evolution of the conceptualisation of negative symptoms, the most important findings, and the remaining open questions. Several studies have shown that negative symptoms might be primary to schizophrenia or secondary to other factors, and that they cluster in the domains of avolition–apathy an...
Apathy and anhedonia are common syndromes of motivation that are associated with a wide range of brain disorders and have no established therapies. Research using animal models suggests that a useful framework for understanding motivated behaviour lies in effort-based decision making for reward. The neurobiological mechanisms underpinning such decisions have now begun to be determined in individuals with apathy or anhedonia, providing an important foundation for developing new treatments. The fi...
Abstract The severity of depressive symptoms across two discrete mental disorders should be evaluated with the same psychometrically validated tools. In patients with schizophrenia the Calgary Depression Rating Scale (CDSS) is recommended for evaluating depressive symptoms. The aim of this study was to validate the CDSS in patients with major depressive disorder. The CDSS exhibit satisfactory psychometric properties for evaluating depressive symptoms in major depressive disorder. Clinicians and ...
Background Negative symptoms are a core feature of schizophrenia and also found in healthy individuals in subclinical forms. According to the current literature the two negative symptom domains, apathy and diminished expression may have different underlying neural mechanisms. Previous observations suggest that striatal dysfunction is associated with apathy in schizophrenia. However, it is unclear whether apathy is specifically related to ventral or dorsal striatal alterations. Here, we investiga...
Apathy can be defined as a reduction of goal-directed behavior and is a strong predictor for poor functional outcome in schizophrenia. However, no objective measure of apathy has been identified and assessment is limited to retrospective interview-based ratings. Here we aimed to identify more precise objective readouts of apathy for translational research and clinical practice.
Last. Mario Amore(UniGe: University of Genoa)H-Index: 59
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Rates of 50–70% of residual symptoms referring to subsyndromal manifestations between episodes that do not meet the required criteria for episode definition were reported in bipolar disorder (BD). However, the specific role of these symptoms on the course of BD patients is poorly understood; thus, we aimed to investigate factors associated with depressive residual symptoms. Overall, 255 currently euthymic BD outpatients on maintenance treatment, including 95 (37.2%) males and 160 (62.8%) females...
#2Egill Rostrup(Copenhagen University Hospital)H-Index: 61
Last. Birte Glenthøj(Copenhagen University Hospital)H-Index: 45
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Background. Negative symptoms (NS) are a central part of the symptomatology of schizophrenia, which is highly correlated to the functional outcome. Disturbances of the brain reward system are suggested to be central in the pathogenesis of NS by decreasing motivation and hedonic experiences. In this study, we compared reward-related brain activity in patients improving and not improving in NS after treatment with amisulpride. Methods. Thirty-nine antipsychotic-naive patients and 49 healthy contro...
Background The relationship between residual depressive symptoms, cognition and functioning in patients with euthymic bipolar disorder is a subject of debate. Aims To assess whether cognition mediates the association between residual depressive symptoms and functioning in patients with bipolar disorder who were euthymic. Method We included 241 adults with euthymic bipolar disorder in a multicentre cross-sectional study. We used a battery of tests to assess six cognition domains. A path analysis ...
Last. Philip Gerretsen(U of T: University of Toronto)H-Index: 23
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Abstract Background Motivational deficits represent a core negative symptom in patients with schizophrenia. Previous morphology studies have demonstrated that apathy in patients with schizophrenia is associated with reduced frontal grey matter (GM). We attempted to replicate this previous finding, and explored whether it was distinct from potential associations with a distinct subdomain of negative symptoms, namely Affective Flattening, and GM. Methods Twenty medicated patients with schizophreni...
Tryptophan and its catabolites (TRYCATs) have been suggested to link peripheral immune system activation and central neurotransmitter abnormalities with relevance to the etio-pathophysiology of schizophrenia (SZ) and major depressive disorder (MDD). The relationship to different psychopathological dimensions within these disorders however remains to be elucidated. We thus investigated potential group differences of tryptophan, kynurenine, kynurenic acid, 3-hydroxy kynurenine and quinolinic acid ...
Last. Antonio Lobo(University of Zaragoza)H-Index: 52
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Purpose of review From the perspective of motivated behaviour and the so-called 'precision psychiatry', we try to identify recent advances in the neurocognitive and biological correlates of apathy. Recent findings New evidence supports the notion that apathy is a common transdiagnostic and heterogeneous clinical syndrome, now conceptualized as a reduction in 'goal-directed' activity. Similarly, abundant evidence has been found related to neurocognitive correlates of apathy and the associations b...
One aspect of goal-directed behavior, which is known to be impaired in patients with schizophrenia (SZ), is balancing between exploiting a familiar choice with known reward value and exploring a lesser known, but potentially more rewarding option. Despite its relevance to several symptom domains of SZ, this has received little attention in SZ research. In addition, while there is increasing evidence that SZ is associated with chronic low-grade inflammation, few studies have investigated how this...
#1Achim Burrer(UZH: University of Zurich)H-Index: 2
#2Fernando Caravaggio(CAMH: Centre for Addiction and Mental Health)H-Index: 20
Last. Matthias Kirschner(Montreal Neurological Institute and Hospital)H-Index: 17
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Abstract Background A growing body of neuroimaging research has revealed a relationship between blunted activation of the ventral striatum (VS) and apathy in schizophrenia. In contrast, the association between reduced striatal volume and apathy is less well established, while the relationship between VS function and structure in patients with schizophrenia remains an open question. Here, we aimed to replicate previous structural findings in a larger independent sample and to investigate the rela...
#2Arielle Rabinowitz(Montreal Neurological Institute and Hospital)H-Index: 1
Last. Alain Dagher(Montreal Neurological Institute and Hospital)H-Index: 73
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The tendency to engage in addictive behaviors has long been tied to the actions of the dopamine system. Early theories were based on the fact that all addictive drugs and behaviors (such as gambling) increase dopamine levels in the striatum, and the evidence that dopamine signaled reward or reward prediction error. However, with a changing emphasis of addiction away from purely pharmacological models that emphasize tolerance and withdrawal, towards one of behavioral dyscontrol, is there still a ...
Abstract (249 of 250 words) Background High trait impulsive sensation seeking (ISS), the tendency to engage in behavior without forethought and to seek out new/extreme experiences, is a transdiagnostic risk factor for externalizing and mood disorders, particularly bipolar disorder (BD). We published a positive association between trait ISS and reward expectancy-related activity in the left ventrolateral prefrontal cortex (L vlPFC) and ventral striatum (VS). We aimed to replicate this finding and...
Last. Dominic B. Dwyer(LMU: Ludwig Maximilian University of Munich)H-Index: 17
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Negative symptoms occur frequently in individuals at clinical high risk (CHR) for psychosis and contribute to functional impairments. The aim of this study was to predict negative symptom severity in CHR after 9 months. Predictive models either included baseline negative symptoms measured with the Structured Interview for Psychosis-Risk Syndromes (SIPS-N), whole-brain gyrification, or both to forecast negative symptoms of at least moderate severity in 94 CHR. We also conducted sequential risk st...
Background: A growing body of neuroimaging research has revealed a relationship between blunted activation of the ventral striatum (VS) and apathy in schizophrenia. In contrast, the association between reduced striatal volume and apathy is less well established, while the relationship between VS function and structure in patients with schizophrenia remains an open question. Here, we aimed to replicate previous structural findings in a larger independent sample and to investigate the relationship...
