![]() The study from Caravaggio and colleagues also extended previous work showing in 41 older schizophrenia patients that the relationship between VS volume was specifically related to individual levels of amotivation (not diminished expression) and independent of antipsychotic occupancy of striatal dopamine D2/3 receptors measured with positron emission tomography ( Caravaggio et al., 2018a). ![]() This finding was replicated by Caravaggio and colleagues who observed a relationship between apathy (PANSS amotivation factor) and both left and right VS volume using a different method – the “Multiple Automatically Generated Templates (MAGeT-Brain)” algorithm ( Caravaggio et al., 2018a). found that apathy (measured with the Apathy Evaluation Scale) was associated with reduced right VS volume, but not left VS volume, in 23 individuals with a diagnosis of schizophrenia or schizoaffective disorder ( Roth et al., 2016). Using Voxel-based morphometry, Roth et al. Two studies investigated correlative relationships between VS volume and measures of apathy ( Caravaggio et al., 2018a Roth et al., 2016), while one study compared subcortical volumes (including caudate, putamen and accumbens) between patients with persistent apathy and patients without apathy ( Morch-Johnsen et al., 2015). To our knowledge only three studies have directly investigated the association between apathy and subcortical structural abnormalities. While most studies in schizophrenia found reduced blood-oxygen-level-dependent (BOLD) activity related to apathy in the ventral striatum (VS), some studies have identified a specific involvement of the dorsal striatum (DS) ( Morris et al., 2015 Mucci et al., 2015), or dysfunctions including both VS and DS ( Dowd et al., 2016 Moran et al., 2019 Stepien et al., 2018).Ĭontrasting this wealth of evidence on the relationship between aberrant striatal function and motivational deficits in schizophrenia, potential structural abnormalities of the striatum have received little attention. reward anticipation, prediction error coding, receipt of reward), with most evidence for a relationship to blunted reward anticipation ( Fig. In schizophrenia, numerous studies demonstrated that severity of apathy is associated with blunted striatal response during reward processing (e.g. ![]() This debilitating symptom is prevalent in early disease stages ( Faerden et al., 2010 Fervaha et al., 2015 Lam et al., 2015), associated with poor treatment compliance ( Tattan and Creed, 2001) and is a strong predictor for poor functional outcome and reduced quality of life ( Faerden et al., 2013 Fervaha et al., 2018 Galderisi et al., 2013 Strauss et al., 2013).įrom a neurobiological perspective it has been observed that functional and structural abnormalities within cortico-striatal circuits are critically involved in the pathophysiology of negative symptoms in particular apathy and motivational deficits ( Ehrlich et al., 2012 Haber, 2016 Hovington and Lepage, 2012 Kos et al., 2016 Li et al., 2018 Radua et al., 2015 van Erp et al., 2016 van Erp et al., 2018 Walton et al., 2018). Apathy can be defined as a reduction in motivation and goal-oriented behavior and is a core negative symptom of schizophrenia ( Brown and Pluck, 2000 Marin, 1996).
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