Looking through tinted glasses : depression and social anxiety are related to both interpretation biases and inflexible negative interpretations

Interpretation bias is often theorized to play a critical role in depression and social anxiety. To date, it remains unknown how interpretation bias exerts its toxic effects. Interpretation inflexibility may be an important determinant of how distorted interpretations affect emotional well-being. This study investigated interpretation bias and inflexibility in relation to depression severity and social anxiety. Participants (N = 212) completed a novel cognitive task that simultaneously measured bias and inflexibility in the interpretation of unfolding ambiguous situations. Depression severity was associated with increased negative and decreased positive interpretation biases. Social anxiety was associated with increased negative interpretation bias. Critically, both symptom types were related to reduced revision of negative interpretations by disconfirmatory positive information. These findings suggest that individuals with more severe depression or social anxiety make more biased and inflexible interpretations. Future work examining cognitive risk for depression and anxiety could benefit from examining both these factors

Alterations in white matter microstructure in neurofibromatosis-1.

Neurofibromatosis (NF1) represents the most common single gene cause of learning disabilities. NF1 patients have impairments in frontal lobe based cognitive functions such as attention, working memory, and inhibition. Due to its well-characterized genetic etiology, investigations of NF1 may shed light on neural mechanisms underlying such difficulties in the general population or other patient groups. Prior neuroimaging findings indicate global brain volume increases, consistent with neural over-proliferation. However, little is known about alterations in white matter microstructure in NF1. We performed diffusion tensor imaging (DTI) analyses using tract-based spatial statistics (TBSS) in 14 young adult NF1 patients and 12 healthy controls. We also examined brain volumetric measures in the same subjects. Consistent with prior studies, we found significantly increased overall gray and white matter volume in NF1 patients. Relative to healthy controls, NF1 patients showed widespread reductions in white matter integrity across the entire brain as reflected by decreased fractional anisotropy (FA) and significantly increased absolute diffusion (ADC). When radial and axial diffusion were examined we found pronounced differences in radial diffusion in NF1 patients, indicative of either decreased myelination or increased space between axons. Secondary analyses revealed that FA and radial diffusion effects were of greatest magnitude in the frontal lobe. Such alterations of white matter tracts connecting frontal regions could contribute to the observed cognitive deficits. Furthermore, although the cellular basis of these white matter microstructural alterations remains to be determined, our findings of disproportionately increased radial diffusion against a background of increased white matter volume suggest the novel hypothesis that one potential alteration contributing to increased cortical white matter in NF1 may be looser packing of axons, with or without myelination changes. Further, this indicates that axial and radial diffusivity can uniquely contribute as markers of NF1-associated brain pathology in conjunction with the typically investigated measures

Connectivity-enhanced diffusion analysis reveals white matter density disruptions in first episode and chronic schizophrenia.

Reduced fractional anisotropy (FA) is a well-established correlate of schizophrenia, but it remains unclear whether these tensor-based differences are the result of axon damage and/or organizational changes and whether the changes are progressive in the adult course of illness. Diffusion MRI data were collected in 81 schizophrenia patients (54 first episode and 27 chronic) and 64 controls. Analysis of FA was combined with "fixel-based" analysis, the latter of which leverages connectivity and crossing-fiber information to assess both fiber bundle density and organizational complexity (i.e., presence and magnitude of off-axis diffusion signal). Compared with controls, patients with schizophrenia displayed clusters of significantly lower FA in the bilateral frontal lobes, right dorsal centrum semiovale, and the left anterior limb of the internal capsule. All FA-based group differences overlapped substantially with regions containing complex fiber architecture. FA within these clusters was positively correlated with principal axis fiber density, but inversely correlated with both secondary/tertiary axis fiber density and voxel-wise fiber complexity. Crossing fiber complexity had the strongest (inverse) association with FA (r = -0.82). When crossing fiber structure was modeled in the MRtrix fixel-based analysis pipeline, patients exhibited significantly lower fiber density compared to controls in the dorsal and posterior corpus callosum (central, postcentral, and forceps major). Findings of lower FA in patients with schizophrenia likely reflect two inversely related signals: reduced density of principal axis fiber tracts and increased off-axis diffusion sources. Whereas the former confirms at least some regions where myelin and or/axon count are lower in schizophrenia, the latter indicates that the FA signal from principal axis fiber coherence is broadly contaminated by macrostructural complexity, and therefore does not necessarily reflect microstructural group differences. These results underline the need to move beyond tensor-based models in favor of acquisition and analysis techniques that can help disambiguate different sources of white matter disruptions associated with schizophrenia

When negative interpretations persist, positive emotions don't! Inflexible negative interpretations encourage depression and social anxiety by dampening positive emotions

Research on emotion regulation difficulties has been instrumental in understanding hallmark features of depression and social anxiety. Yet, the cognitive mechanisms that give rise to maladaptive patterns of emotion regulation strategy use remain underspecified. This investigation examined the association of negative interpretation inflexibility and interpretation biases with the use of common emotion regulation strategies in response to negative and positive emotional experiences (repetitive negative thinking, positive reappraisal, and dampening). Study 1 (N = 250) found that inflexibility in revising negative interpretations in response to disconfirmatory positive information was related to the dampening of positive emotions, but not to repetitive negative thinking or positive reappraisal. Importantly, dampening mediated the relation between inflexible negative interpretations and symptoms of both depression and social anxiety. This mediation model was further supported by the data from Study 2 (N = 294). Across both studies, negative interpretation bias was related to repetitive negative thinking and dampening, whereas positive interpretation bias was related to positive reappraisal. Collectively, these results suggest that both interpretation inflexibility and interpretation biases may contribute to difficulties in emotion regulation related to depression and social anxiety

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

Comprehensive analysis of copy number variation in monozygotic twins discordant for bipolar disorder or schizophrenia

Copy number variation plays a clear role in the etiology of many psychiatric disorders, particularly schizophrenia. We performed array-CGH to look for copy number variants between five pairs of monozygotic twins discordant for bipolar disorder or schizophrenia. Our study found no differences in copy number variants between the sets of twins. Although alluring, realistic accounting for heterogeneity and chimerism highlight the technological limitations in studying monozygotic twins discordant for psychiatric disorders

Family-Focused Treatment for Adolescents and Young Adults at High Risk for Psychosis: Results of a Randomized Trial

Objective: Longitudinal studies have begun to clarify the phenotypic characteristics of adolescents and young adults at clinical high risk for psychosis. This 8-site randomized trial examined whether a 6-month program of family psychoeducation was effective in reducing the severity of attenuated positive and negative psychotic symptoms and enhancing functioning among individuals at high risk. Method: Adolescents and young adults (mean age 17.4 +/- 4.1 years) with attenuated positive psychotic symptoms, brief and intermittent psychosis, or genetic risk with functional deterioration were randomly assigned to 18 sessions of family-focused therapy for individuals at clinical high risk (FFT-CHR) in 6 months or 3 sessions of family psychoeducation (enhanced care [EC]. FFT-CHR included psychoeducation about early signs of psychosis, stress management, communication training, and problem-solving skills training, whereas EC focused on symptom prevention. Independent evaluators assessed participants at baseline and 6 months on positive and negative symptoms and social-role functioning. Results: Of 129 participants, 102 (79.1%) were followed up at 6 months. Participants in FFT-CHR showed greater improvements in attenuated positive symptoms over 6 months than participants in EC (F-1,F-97 = 5.49, p = .02). Negative symptoms improved independently of psychosocial treatments. Changes in psychosocial functioning depended on age: participants more than 19 years of age showed more role improvement in FFT-CHR, whereas participants between 16 and 19 years of age showed more role improvement in EC. The results were independent of concurrent pharmacotherapy. Conclusion: Interventions that focus on improving family relationships may have prophylactic efficacy in individuals at high risk for psychosis. Future studies should examine the specificity of effects of family intervention compared to individual therapy of the same duration and frequency. Clinical trial registration information-Prevention Trial of Family Focused Treatment in Youth at Risk for Psychosis