Correlates of frequent gambling and gambling-related chasing behaviors in individuals with schizophrenia-spectrum disorders

Background and aims Published research on the relationship between disordered gambling and schizophrenia is limited. However, existing data suggest that individuals with schizophrenia/schizoaffective disorder may have a high prevalence of co-occurring disordered gambling. As such, effective strategies for screening and assessing gambling-related problems in individuals with psychosis are needed. The goal of this study was to explore the correlates of increased gambling frequency and chasing behavior, a hallmark feature of gambling disorder, in a sample of individuals with schizophrenia and schizoaffective disorders. Methods Data from 336 participants who met DSM-IV criteria for schizophrenia or schizoaffective disorder were used to examine differences between non-gamblers, infrequent gamblers, frequent gamblers who do not report chasing, and frequent gamblers who report chasing on a variety of associated features and symptoms of schizophrenia and disordered gambling. Results and discussion The results of the study support the conclusion that chasing behavior in individuals with schizophrenia/schizoaffective disorder lies on a continuum of severity, with more frequent gamblers endorsing greater chasing. Chasing was also associated with indicators of lower functioning across co-occurring disorders, such as greater problems with alcohol and drugs, greater gambling involvement, and a family history of gambling problems. The findings from the study suggest the utility of screening for chasing behavior as a brief and efficient strategy for assessing risk of gambling problems in individuals with psychotic-spectrum disorders

Cerebrospinal fluid microglia and neurodegenerative markers in twins concordant and discordant for psychotic disorders

International audienceThe jacket type offshore wind turbine transfers efficiently the horizontal load applied on the wind turbine to an axial load on the four piles of its foundation. The axial behaviour of one single pile of the foundation is investigated in a geotechnical centrifuge. The model pile, tested under a 100 g centrifuge acceleration, is designed to represent a cast-in-place pile with a 1.8 m diameter and a 40 m embedded length. The pile, installed in dense Fontainebleau sand, is instrumented with a load sensor at its end to measure the tip resistance. By subtracting the total load applied on the pile, its shaft capacity is also calculated. Different axial loading paths are applied: i) monotonic loadings in compression and tension to obtain ultimate capacities and ii) cyclic loadings which represent a more realistic loading path applied by the jacket during its life time in order to observe the tip and shaft capacities reductions

Perseverant Cognitive Effort and Disengagement

Willingness to expend effort has received increased attention over the past decade, and for good reason – effort is crucial to life's successes, and many of us wish we could harness and control it more optimally. In particular, cognitive effort is central to academic and vocational achievements. Though effort is important, it is also costly. If it were not, no projects would be left unfinished, and no treadmills would be abandoned early. Because it is costly, self-control is often required to exert and maintain effort. Reduced willingness to expend effort has also come into focus as a clinically relevant variable related to amotivation, most notably in schizophrenia. Additionally, both incentive motivation (immediate monetary reward availability) and effort have been linked with cognitive performance, suggesting that our measures of cognitive ability are inexorably linked to and to some degree confounded by cognitive effort. In this dissertation, I present a novel paradigm developed for the assessment of perseverant cognitive effort in the absence of monetary incentive. The Cognitive Effort and DisEngagement (CEDE) task is a cognitive test that increases in difficulty and measures perseverant effort disengagement in a simple but novel way: participants are permitted to skip trials without penalty. The present work introduces the task, situates it within a framework of self-control divided into inhibitory and actuating mechanisms, and provides evidence of its association with stable traits, context, and psychosis. The first set of studies (Chapter 1) tests the reliability and validity of the CEDE task in an undergraduate sample and a community sample. We find evidence of high internal consistency using a split-half method. We also find that skips on the CEDE show convergent validity in terms of correlation with self-reported perseverance and work ethic, as well as discriminant validity, showing lack of significant relationships with several theoretically distinct aspects of self-control. We also show evidence of tolerability of the paradigm and of face validity of skipping as an index of effort disengagement. In Chapter 2, we test the effect of observation on perseverant effort on the CEDE task. We find that participants skip significantly more trials when they are observed by an experimenter with access to information about their performance via sound effects, compared with than when they have privacy (when the experimenter leaves the room, or when the participant wears headphones). We also find that self-reported internal motivational style predicts more perseverant effort when in private, whereas external motivational style predicts more effort when observed, suggesting that motivational styles exert influence differentially depending on features of the context. We also show that self-reported stress during the task negatively predicts performance, and that this relationship is fully mediated by skips. These results suggest that observation has a potent effect on cognitive task effort, affecting people differently according to motivational style, and that test anxiety also promotes effort disengagement. In Chapter 3, we test for group differences in skips between individuals with first episode psychosis (FEP) and community controls, as schizophrenia is associated with both a cognitive and a motivational impairment. We show reduced perseverant cognitive effort on the CEDE in FEP. We find that this group difference specifically emerges during difficult trials, suggesting specifically a deficit in perseverance in reaction to difficulty rather than continuous attention throughout the test. We also show that reduction of effort in the form of skips is correlated with self-reported amotivation among patients. These results suggest clinical relevance of perseverant cognitive effort in schizophrenia as a component or reflection of motivational impairments. Together, these findings provide novel insight into cognitive effort perseverance, its relationship to non-monetary motivations in terms of motivational style and observational context, and its reduction in psychosis. Our findings also highlight the relevance of cognitive effort perseverance to cognitive testing. Willingness to expend cognitive effort appears to be sensitive to numerous factors in the context of difficulty, when the demands on effort are higher, whereas it is relatively steadfast during easier tasks

Cerebrospinal fluid microglia and neurodegenerative markers in twins concordant and discordant for psychotic disorders.

Schizophrenia and bipolar disorder are debilitating psychiatric disorders with partially shared symptomatology including psychotic symptoms and cognitive impairment. Aberrant levels of microglia and neurodegenerative cerebrospinal fluid (CSF) markers have previously been found in schizophrenia and bipolar disorder. We aimed to analyze familial and environmental influences on these CSF markers and their relation to psychiatric symptoms and cognitive ability. CSF was collected from 17 complete twin pairs, nine monozygotic and eight dizygotic, and from one twin sibling. Two pairs were concordant for schizophrenia, and 11 pairs discordant for schizophrenia, schizoaffective disorder or bipolar disorder, and four pairs were not affected by psychotic disorders. Markers of microglia activation [monocyte chemoattractant protein-1 (MCP-1), chitinase 3-like protein 1 (YKL-40), and soluble cluster of differentiation 14 (sCD14)], markers of β-amyloid metabolism (AβX-38, AβX-40, AβX-42 and Aβ1-42), soluble amyloid precursor proteins (sAPP-α and sAPP-β), total tau (T-tau), phosphorylated tau (P-tau), and CSF/serum albumin ratio were measured in CSF using immunoassays. Heritability of the CSF markers was estimated, and associations to psychiatric and cognitive measurements were analyzed. Heritability estimates of the microglia markers were moderate, whereas several neurodegenerative markers showed high heritability. In contrast, AβX-42, Aβ1-42, P-tau and CSF/serum albumin ratio were influenced by dominant genetic variation. Higher sCD14 levels were found in twins with schizophrenia or bipolar disorder compared to their not affected co-twins, and higher sCD14-levels were associated with psychotic symptoms. The study provides support for a significant role of sCD14 in psychotic disorders and a possible role of microglia activation in psychosis