Structural brain patterns in Anorexia Nervosa: a multimodal MRI evaluation

Introduction. Cortical and white matter structural abnormalities in Anorexia Nervosa (AN) have been recently investigated, but no attempt has been made to explore the organizational patterns that govern the relationships between different brain areas and to characterize the neurobiology of the disorder in the different stages of its course. Aims of the present work are to characterize cortical and white matter network architecture by means of different structural indices and computational techniques, to observe the presence of any correlation between clinical variables and networks characteristics and to investigate the structural organizational patterns in the different stage of AN course. Methods and Materials. 38 patients with acute AN, 38 healthy controls and 20 patients in full remission from AN were included in this study. All participants underwent high-resolution MRI. An analysis of cortical structural co-variance was performed using cortical thickness and gyrification indices. The anatomical complexity of the cortex was explored by means of Fractal Dimension (FD). Connectomic tools were applied to DTI tractography data to investigate the white matter network architecture. Results. Patients with AN showed unbalanced integration and segregation properties in cortical thickness, gyrification and DTI networks both on global and regional levels. Patients with a poor outcome at a three years follow-up assessment showed higher segregation measures and lower small-worldness in the gyrification network. The FD analysis revealed a reduced cortical complexity in the AN group. Discussion. Alterations in structural covariance patterns in AN are likely to reflect the metabolic consequences of the disorder as well as deviations in normal developmental trajectories. Lower FD in AN indicates a reduction of cortical complexity in the acute stages of the disorder and evidenced that this structural index is sensitive to the effects of malnutrition

Linguistic embodiment in typical and atypical anorexia nervosa: Evidence from an image-word matching task

Objective: The integration of sensory, motor, and cognitive systems is embodied cognition, according to which mind and body are not separate and distinct, and our body (and our brain, as part of the body) contributes to determining our mental and cognitive processes. In spite of limited data available, Anorexia nervosa (AN) appears as a condition in which embodied cognition is altered, in particular, if we consider bodily sensations and visuospatial information processing. We aimed to evaluate the ability to correctly identify body parts and actions in both full (AN) and atypical AN (AAN), looking at the role of the underweight status. Method: A group of 143 females (AN = 45, AAN = 43, unaffected women = 55) was enrolled. All participants performed a linguistic embodied task to evaluate the association between a picture-showing a bodily action-and a written verb. Additionally, a subsample of 24 AN participants performed a retest after stable weight recovery. Results: Both AN and AAN demonstrated an abnormal ability to evaluate the picture-written verb associations, especially if the involved bodily effectors were the same in both stimuli (i.e., pictorial and verbal) and needed a longer response time. Conclusions: Specific embodied cognition linked to body schema seems to be impaired in persons with AN. The longitudinal analysis showed a difference between AN and AAN only in the underweight condition, suggesting the presence of an abnormal linguistic embodiment. More attention should be devoted to embodiment during AN treatment to improve bodily cognition, which might, in turn, diminish body misperception

Cortical Complexity Estimation Using Fractal Dimension: A Systematic Review of the Literature on Clinical and Nonclinical Samples

Fractal geometry has recently been proposed as a useful tool for characterizing the complexity of the brain cortex, which is likely to derive from the recurrence of sulci–gyri convolution patterns. The index used to describe the cortical complexity is called fractal dimensional (FD) and was employed by different research exploring the neurobiological correlates of distinct pathological and nonpathological conditions. This review aims to describe the literature on the application of this index, summarize the heterogeneities between studies and inform future research on this topic. Sixty-two studies were included in the systematic review. The main research lines concern neurodevelopment, aging and the neurobiology of specific psychiatric and neurological disorders. Overall, the included papers indicate that cortical complexity is likely to reduce during aging and in various pathological processes affecting the brain. Nevertheless, the high heterogeneity between studies strongly prevents the possibility of drawing conclusions. Further research considering this index besides other morphological values is needed to better clarify the role of FD in characterizing the cortical structure

The influence of autistic symptoms on social and non-social cognition and on real-life functioning in people with schizophrenia: Evidence from the Italian Network for Research on Psychoses multicenter study

BACKGROUND: Autism spectrum disorders (ASDs) and schizophrenia spectrum disorders (SSDs), although conceptualized as separate entities, may share some clinical and neurobiological features. ASD symptoms may have a relevant role in determining a more severe clinical presentation of schizophrenic disorder but their relationships with cognitive aspects and functional outcomes of the disease remain to be addressed in large samples of individuals. AIMS: To investigate the clinical, cognitive, and functional correlates of ASD symptoms in a large sample of people diagnosed with schizophrenia. METHODS: The severity of ASD symptoms was measured with the PANSS Autism Severity Scale (PAUSS) in 921 individuals recruited for the Italian Network for Research on Psychoses multicenter study. Based on the PAUSS scores, three groups of subjects were compared on a wide array of cognitive and functional measures. RESULTS: Subjects with more severe ASD symptoms showed a poorer performance in the processing speed (p\ua0=\ua00.010), attention (p\ua0=\ua00.011), verbal memory (p\ua0=\ua00.035), and social cognition (p\ua0=\ua00.001) domains, and an overall lower global cognitive composite score (p\ua0=\ua00.010). Subjects with more severe ASD symptoms also showed poorer functional capacity (p\ua0=\ua00.004), real-world interpersonal relationships (p\ua0<\ua00.001), and participation in community-living activities (p\ua0<\ua00.001). CONCLUSIONS: These findings strengthen the notion that ASD symptoms may have a relevant impact on different aspects of the disease, crucial to the life of people with schizophrenia. Prominent ASD symptoms may characterize a specific subpopulation of individuals with SSD

Does social cognition change? Evidence after 4 years from the Italian Network for Research on Psychoses

Background Deficits in social cognition (SC) are significantly related to community functioning in schizophrenia (SZ). Few studies investigated longitudinal changes in SC and its impact on recovery. In the present study, we aimed: (a) to estimate the magnitude and clinical significance of SC change in outpatients with stable SZ who were assessed at baseline and after 4 years, (b) to identify predictors of reliable and clinically significant change (RCSC), and (c) to determine whether changes in SC over 4 years predicted patient recovery at follow-up. Methods The reliable change index was used to estimate the proportion of true change in SC, not attributable to measurement error. Stepwise multiple logistic regression models were used to identify the predictors of RCSC in a SC domain (The Awareness of Social Inference Test [TASIT]) and the effect of change in TASIT on recovery at follow-up. Results In 548 participants, statistically significant improvements were found for the simple and paradoxical sarcasm of TASIT scale, and for the total score of section 2. The reliable change index was 9.8. A cut-off of 45 identified patients showing clinically significant change. Reliable change was achieved by 12.6% and RCSC by 8% of participants. Lower baseline TASIT sect. 2 score predicted reliable improvement on TASIT sect. 2. Improvement in TASIT sect. 2 scores predicted functional recovery, with a 10-point change predicting 40% increase in the probability of recovery. Conclusions The RCSC index provides a conservative way to assess the improvement in the ability to grasp sarcasm in SZ, and is associated with recovery

Insight in cognitive impairment assessed with the Cognitive Assessment Interview in a large sample of patients with schizophrenia

The Cognitive Assessment Interview (CAI) is an interview-based scale measuring cognitive impairment and its impact on functioning in subjects with schizophrenia (SCZ). The present study aimed at assessing, in a large sample of SCZ (n = 601), the agreement between patients and their informants on CAI ratings, to explore patients' insight in their cognitive deficits and its relationships with clinical and functional indices. Agreement between patient- and informant-based ratings was assessed by the Gwet's agreement coefficient. Predictors of insight in cognitive deficits were explored by stepwise multiple regression analyses. Patients reported lower severity of cognitive impairment vs. informants. A substantial to almost perfect agreement was observed between patients' and informants' ratings. Lower insight in cognitive deficits was associated to greater severity of neurocognitive impairment and positive symptoms, lower severity of depressive symptoms, and older age. Worse real-life functioning was associated to lower insight in cognitive deficit, worse neurocognitive performance, and worse functional capacity. Our findings indicate that the CAI is a valid co-primary measure with the interview to patients providing a reliable assessment of their cognitive deficits. In the absence of informants with good knowledge of the subject, the interview to the patient may represent a valid alternative

Accuracy of self-assessment of real-life functioning in schizophrenia

A consensus has not yet been reached regarding the accuracy of people with schizophrenia in self-reporting their real-life functioning. In a large (n=618) cohort of stable, community-dwelling schizophrenia patients we sought to: (1) examine the concordance of patients' reports of their real-life functioning with the reports of their key caregiver; (2) identify which patient characteristics are associated to the differences between patients and informants. Patient-caregiver concordance of the ratings in three Specific Level of Functioning Scale (SLOF) domains (interpersonal relationships, everyday life skills, work skills) was evaluated with matched-pair t tests, the Lin's concordance correlation, Somers' D, and Bland-Altman plots with limits of agreement (LOA). Predictors of the patient-caregiver differences in SLOF ratings were assessed with a linear regression with multivariable fractional polynomials. Patients' self-evaluation of functioning was higher than caregivers' in all the evaluated domains of the SLOF and 17.6% of the patients exceeded the LOA, thus providing a self-evaluation discordant from their key caregivers. The strongest predictors of patient-caregiver discrepancies were caregivers' ratings in each SLOF domain. In clinically stable outpatients with a moderate degree of functional impairment, self-evaluation with the SLOF scale can become a useful, informative and reliable clinical tool to design a tailored rehabilitation program

The interplay among psychopathology, personal resources, context-related factors and real-life functioning in schizophrenia: stability in relationships after 4 years and differences in network structure between recovered and non-recovered patients

Improving real-life functioning is the main goal of the most advanced integrated treatment programs in people with schizophrenia. The Italian Network for Research on Psychoses previously explored, by using network analysis, the interplay among illness-related variables, personal resources, context-related factors and real-life functioning in a large sample of patients with schizophrenia. The same research network has now completed a 4-year follow-up of the original sample. In the present study, we used network analysis to test whether the pattern of relationships among all variables investigated at baseline was similar at follow-up. In addition, we compared the network structure of patients who were classified as recovered at follow-up versus those who did not recover. Six hundred eighteen subjects recruited at baseline could be assessed in the follow-up study. The network structure did not change significantly from baseline to follow-up, and the overall strength of the connections among variables increased slightly, but not significantly. Functional capacity and everyday life skills had a high betweenness and closeness in the network at follow-up, as they had at baseline, while psychopathological variables remained more peripheral. The network structure and connectivity of non-recovered patients were similar to those observed in the whole sample, but very different from those in recovered subjects, in which we found few connections only. These data strongly suggest that tightly coupled symptoms/dysfunctions tend to maintain each other's activation, contributing to poor outcome in schizophrenia. Early and integrated treatment plans, targeting variables with high centrality, might prevent the emergence of self-reinforcing networks of symptoms and dysfunctions in people with schizophrenia

The interplay among psychopathology, personal resources, context-related factors and real-life functioning in schizophrenia: stability in relationships after 4 years and differences in network structure between recovered and non-recovered patients

Improving real-life functioning is the main goal of the most advanced integrated treatment programs in people with schizophrenia. The Italian Network for Research on Psychoses previously explored, by using network analysis, the interplay among illness-related variables, personal resources, context-related factors and real-life functioning in a large sample of patients with schizophrenia. The same research network has now completed a 4-year follow-up of the original sample. In the present study, we used network analysis to test whether the pattern of relationships among all variables investigated at baseline was similar at follow-up. In addition, we compared the network structure of patients who were classified as recovered at follow-up versus those who did not recover. Six hundred eighteen subjects recruited at baseline could be assessed in the follow-up study. The network structure did not change significantly from baseline to follow-up, and the overall strength of the connections among variables increased slightly, but not significantly. Functional capacity and everyday life skills had a high betweenness and closeness in the network at follow-up, as they had at baseline, while psychopathological variables remained more peripheral. The network structure and connectivity of non-recovered patients were similar to those observed in the whole sample, but very different from those in recovered subjects, in which we found few connections only. These data strongly suggest that tightly coupled symptoms/dysfunctions tend to maintain each other's activation, contributing to poor outcome in schizophrenia. Early and integrated treatment plans, targeting variables with high centrality, might prevent the emergence of self-reinforcing networks of symptoms and dysfunctions in people with schizophrenia

Structural brain patterns in Anorexia Nervosa: a multimodal MRI evaluation

Introduction. Cortical and white matter structural abnormalities in Anorexia Nervosa (AN) have been recently investigated, but no attempt has been made to explore the organizational patterns that govern the relationships between different brain areas and to characterize the neurobiology of the disorder in the different stages of its course. Aims of the present work are to characterize cortical and white matter network architecture by means of different structural indices and computational techniques, to observe the presence of any correlation between clinical variables and networks characteristics and to investigate the structural organizational patterns in the different stage of AN course. Methods and Materials. 38 patients with acute AN, 38 healthy controls and 20 patients in full remission from AN were included in this study. All participants underwent high-resolution MRI. An analysis of cortical structural co-variance was performed using cortical thickness and gyrification indices. The anatomical complexity of the cortex was explored by means of Fractal Dimension (FD). Connectomic tools were applied to DTI tractography data to investigate the white matter network architecture. Results. Patients with AN showed unbalanced integration and segregation properties in cortical thickness, gyrification and DTI networks both on global and regional levels. Patients with a poor outcome at a three years follow-up assessment showed higher segregation measures and lower small-worldness in the gyrification network. The FD analysis revealed a reduced cortical complexity in the AN group. Discussion. Alterations in structural covariance patterns in AN are likely to reflect the metabolic consequences of the disorder as well as deviations in normal developmental trajectories. Lower FD in AN indicates a reduction of cortical complexity in the acute stages of the disorder and evidenced that this structural index is sensitive to the effects of malnutrition