Dimensional Measures Research Articles

Self-other referential neural processing in social anxiety disorder and major depressive disorder

BackgroundSocial anxiety disorder (SAD) and major depressive disorder (MDD) are highly comorbid and share impairments in self-referential and social processing. Many naturalistic judgements activate these processes concurrently, which can be referred to as “self-other referential processing”. We sought to examine its neural correlates in young people with SAD and MDD using a novel experimental task. MethodsFifty six young people aged 16 to 25 with diagnoses of SAD and/or MDD (15 with SAD [M = 20.3 years, 60% female], 17 with MDD [M = 19.8 years, 53% female], 24 with comorbid SAD and MDD [M = 19.8 years, 67% female]) and 76 age and gender-matched healthy controls (HCs; M = 20.7 years, 66% female) completed a novel self-other referential processing fMRI task that involved rating how much one related to emotional faces in active conditions and judging how far apart each person’s eyes were in control conditions. ResultsParticipants with SAD had more and those with MDD had less activity in social cognitive areas than HCs when processing social information across all conditions and emotion types. Participants with comorbid SAD-MDD exhibited a distinct pattern of neural activity to patients with single diagnoses. Across the whole sample, the activation of reward system areas (the medial orbitofrontal cortex and caudate) in response to increasing relatedness correlated positively with a dimensional measure of social anxiety. ConclusionsYoung people with SAD, MDD and comorbid SAD-MDD showed deficits in social processing, but they were not specifically related to self-other referential processing. Dimensional social anxiety symptoms were correlated with reward system activation, suggesting that such symptoms are associated with an overestimation of the hedonic value of social stimuli. These novel findings have implications for our understanding of the neural correlates of SAD and MDD, suggesting that alterations in social processing and reward functioning underlie the impairments in self and social processing that characterize both disorders.

Measure of the density of quantum states in information geometry and quantum multiparameter estimation

Recently, there is a growing interest in study quantum mechanics from the information geometry perspective, where a quantum state is depicted with a point in the projective Hilbert space. By taking quantum Fisher information (QFI) as the metric of projective Hilbert spaces, estimating a small parameter shift is equivalent to distinguishing neighboring quantum states along a given curve. Henceforth, information geometry plays a significant role in the single parameter estimation. However, the absence of high dimensional measures limits its applications in studying the multi-parameter systems. In this paper, we will discuss the physical implications of the volume element of QFI. It measures the intrinsic density of quantum states (IDQS) in projective Hilbert spaces, which is, then, a measure to define the (over) completeness relation of a class of quantum states. As an application, IDQS can be used in quantum measurement and multi-parameter estimation. We find the density of distinguishable states (DDS) for a set of efficient estimators is measured by the invariant volume of the classical Fisher information, which is the classical counterpart of QFI and serves as the metric of statistical manifolds. Correspondingly, a determinant form of quantum Cram\'{e}r-Rao inequality is proposed to quantify the ability to infer the IDQS via quantum measurement. As a result, we find a gap between IDQS and maximal DDS over the measurements. The gap has tight connections with the uncertainty relationship. Exemplified with the three-level system with two parameters, we find the maximal DDS attained via the \emph{vertex measurements} (MvDDS) equals the square root of the quantum geometric tensor's determinant. It indicates the square gap between IDQS and MvDDS is proportional to the square of Berry curvature.

Protocol for Transcranial Direct Current Stimulation for Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) is a debilitating disorder with an approximate lifetime prevalence of 1–3%. Despite advances in leading treatment modalities, including pharmacotherapy and psychotherapy, some cases remain treatment resistant. Non-invasive brain stimulation has been explored in this treatment-resistant population with some promising findings; however, a lack of methodological rigor has reduced the quality of the findings. The current paper presents the protocol for conducting research into the efficacy of transcranial direct current stimulation (tDCS) in the treatment of OCD. A double-blind randomised controlled trial (RCT) will be conducted involving active tDCS vs. sham tDCS on 40 general OCD patients. The intervention consists of 2 mA anodal stimulation over the pre-supplementary motor area (pre-SMA) with the cathode positioned over the orbitofrontal cortex (OFC). Participants will receive 10 sessions of 20 min of either sham- or active-tDCS over 4 weeks. Outcomes will be categorical and dimensional measures of OCD, as well as related secondary clinical measures (depression, anxiety, quality of life), and neurocognitive functions (inhibitory control, cognitive flexibility).

On principal frequencies and isoperimetric ratios in convex sets

On a convex set, we prove that the Poincare-Sobolev constant for functions vanishing at the boundary can be bounded from above by the ratio between the perimeter and a suitable power of the $N-$dimensional measure. This generalizes an old result by Polya. As a consequence, we obtain the sharp {\it Buser's inequality} (or reverse Cheeger inequality) for the $p-$Laplacian on convex sets. This is valid in every dimension and for every $1<p<+\infty$. We also highlight the appearing of a subtle phenomenon in shape optimization, as the integrability exponent varies.

Fourier decay of fractal measures on hyperboloids

Let $\mu$ be an $\alpha$-dimensional probability measure. We prove new upper and lower bounds on the decay rate of hyperbolic averages of the Fourier transform $\widehat{\mu}$. More precisely, if $\mathbb{H}$ is a truncated hyperbolic paraboloid in $\mathbb{R}^d$ we study the optimal $\beta$ for which $$\int_{\mathbb{H}} |\hat{\mu}(R\xi)|^2 \, d \sigma (\xi)\leq C(\alpha, \mu) R^{-\beta}$$ for all $R > 1$. Our estimates for $\beta$ depend on the minimum between the number of positive and negative principal curvatures of $\mathbb{H}$; if this number is as large as possible our estimates are sharp in all dimensions.

A dimensional measure of schizotypy: cross-cultural adaptation and validation of the Oxford-Liverpool Inventory of Feelings and Experiences short version for Brazilian Portuguese (O-LIFE-S).

Introduction The Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) is a widely-used scale, and the first to include a dimensional approach to understanding schizotypy.Objective To adapt the short version of the O-LIFE (O-LIFE-S) into Brazilian Portuguese.Method a) Two independent bilingual professionals translated the original instrument into Brazilian Portuguese; b) a third bilingual professional summarized the two translations; c) a fourth bilingual expert translated the Portuguese version back into English; d) this back-translation was adjusted by a committee of psychology experts; e) a pilot study was conducted with 10 participants from the general population.Results O-LIFE-S was considered ready to be used in a formal validation study in Brazil.Conclusion The scale appears to cover the dimensional approach to schizotypy. However, a future validation study needs to be conducted to determine the internal consistency and reliability of the Brazilian Portuguese version of the O-LIFE-S .

Computational Modeling of Attentional Impairments in Disruptive Mood Dysregulation and Attention-Deficit/Hyperactivity Disorder

Computational models provide information about cognitive components underlying behavior. When applied to psychopathology-relevant processes, they offer additional insight to observed differences in behavioral performance. Drift diffusion models have been successfully applied to investigate processing efficiency during binary choice tasks. Using these models, we examine the association between psychopathology (irritability and inattention/hyperactivity) and processing efficiency under different attentional demands. A total of 187 youths with attention-deficit/hyperactivity disorder (ADHD), disruptive mood dysregulation disorder (DMDD), both disorders, or no major psychopathology (age, mean ± SD, 13.09 ± 2.55 y, 34% female) completed an Eriksen Flanker task. Of these, 87 youths provided complete data on dimensional measures of the core symptom of DMDD (irritability) and those of ADHD (inattention and hyperactivity). In a categorical diagnosis-based analysis (n= 187), we found significant interactive effects among ADHD, DMDD, and task condition on processing efficiency, whereby changes in processing efficiency between conflict and nonconflict conditions were larger in youths without psychopathology compared with patients. Analysis of symptom severity (n= 87) across diagnoses similarly revealed an interaction between symptom dimensions and task condition on processing efficiency. Irritability moderated the magnitude of association between inattention symptoms and difference in processing efficiency between conflict and nonconflict conditions. Adapting processing efficiency to cognitive demands may represent a shared cognitive endophenotype for both ADHD and DMDD. Highly irritable and/or inattentive youth may have difficulty adjusting processing efficiency to changing task demands, possibly reflecting impairments in cognitive flexibility.

PID-5 Trait Indicators of Emotional Instability and Childhood Adversity Antecedents.

Personality traits provide natural mechanisms through which childhood maltreatment may translate into psychiatric symptomatology. The PID-5 has provided a DSM-supported exemplar for canvassing traits that may contribute to the developmental trajectories of many personality and mood disorders. This general population survey (N = 2,430) examined associations between adverse childhood experiences (ACE questionnaire) and selected PID-5 trait indicators of emotional well-being (Depressivity, Anxiousness, and Emotional Lability). These associations were contrasted with others derived from traditional dimensional measures of childhood maltreatment. ACE counts and all six of the dimensional maltreatment indicators were linked to the three trait scores. Family emotional abuse and ACE counts provided equally strong correlates of Depressivity and Anxiousness. ACE counts and childhood sexual abuse were especially strong in their associations with all three traits. Graded relationships were found in these trait-adversity relationships with polyvictimized respondents generating the highest personality maladjustment. The odds of a trait score elevation (>1 SD) were raised substantially (two to five fold) by singular adversity exposures, and the co-occurrence of only two different forms of adversity maximized odds of extreme trait expression. These results contribute to an evidentiary base suggesting steeper developmental trajectories for personality maladjustment among maltreated youth.

Rethinking Categories and Dimensions in the DSM.

This paper addresses the role of categories and dimensions in the classification of psychopathology. While psychopathology does not sort itself out neatly into natural categories, we do find rough, symptom-based groupings that, through refinement, become diagnostic categories. Given that these categories suffer from comorbidity, uncertain boundaries, and excessive "unspecified disorder" diagnoses, there has been a move toward refining the diagnoses with dimensional measures. The paper traces efforts both to improve the diagnostic categories with validators that allow at least partial validity and to introduce dimensional measures into the diagnostic manual. Drawing from the philosophical pragmatism of Charles Sanders Peirce, William James, and John Dewey, which emphasizes the practical, effect-sensitive consequences of a theory along with an emphasis on empirical evidence and the progressive, probabilistic character of knowledge, the paper argues that these efforts must be guided both by scientific validity and clinical utility.

Sex differences in medial prefrontal and parietal cortex structure in children with disruptive behavior

Sex differences in brain structure in children with disruptive behavior disorders (DBD) remain poorly understood. This study examined sex differences in gray matter volume in children with DBD in a priori regions-of-interest implicated in the pathophysiology of disruptive behavior. We then conducted a whole-brain analysis of cortical thickness to examine sex differences in regions not included in our hypothesis. Exploratory analyses investigated unique associations between structure, and dimensional measures of severity of disruptive behavior and callous-unemotional traits. This cross-sectional study included 88 children with DBD (30 females) aged 8–16 years and 50 healthy controls (20 females). Structural MRI data were analyzed using surface-based morphometry to test for interactions between sex and group. Multiple-regression analyses tested for sex-specific associations between structure, callous-unemotional traits, and disruptive behavior severity. Boys with DBD showed reduced gray matter volume in the left ventromedial prefrontal cortex (vmPFC) and reduced cortical thickness in the supramarginal gyrus, but not girls compared to respective controls. Dimensional analyses revealed associations between sex, callous-unemotional traits, and disruptive behavior for amygdala and vmPFC volume, and ventrolateral prefrontal cortex cortical thickness. Sex-specific differences in prefrontal structures involved in emotion regulation may support identification of neural biomarkers of disruptive behavior to inform target-based treatments.

Reactive attachment disorder and disinhibited social engagement disorder in adolescence: co-occurring psychopathology\xa0and psychosocial problems

Insufficient care is associated with most psychiatric disorders and psychosocial problems, and is part of the etiology of reactive attachment disorder (RAD) and disinhibited social engagement disorder (DSED). To minimize the risk of misdiagnosis, and aid treatment and care, clinicians need to know to which degree RAD and DSED co-occur with other psychopathology and psychosocial problems, a topic little researched in adolescence. In a national study of all adolescents (N = 381; 67% consent; 12–20 years old; 58% girls) in Norwegian residential youth care, the Child and Adolescent Psychiatric Assessment interview yielded information about psychiatric diagnoses and psychosocial problems categorized as present/absent, and the Child Behavior Check List questionnaire was applied for dimensional measures of psychopathology. Most adolescents with a RAD or DSED diagnosis had several cooccurring psychiatric disorders and psychosocial problems. Prevalence rates of both emotional and behavioral disorders were high in adolescent RAD and DSED, as were rates of suicidality, self-harm, victimization from bullying, contact with police, risky sexual behavior and alcohol or drug misuse. Although categorical measures of co-occurring disorders and psychosocial problems revealed few and weak associations with RAD and DSED, dimensional measures uncovered associations between both emotional and behavioral problems and RAD/DSED symptom loads, as well as DSED diagnosis. Given the high degree of comorbidity, adolescents with RAD or DSED—or symptoms thereof—should be assessed for co-occurring psychopathology and related psychosocial problems. Treatment plans should be adjusted accordingly.

Glutamatergic Correlates of Bipolar Symptoms in Adolescents.

Objectives: Prior studies demonstrate elevated cortical glutamate (Glu) in patients with bipolar disorder (BD). Studies assessing neurochemistry in early stages of bipolar illness before the emergence of manic symptoms are lacking. This study aimed to examine neurochemical correlates measured by proton magnetic resonance spectroscopy (1H-MRS) and a dimensional measure of bipolarity in a sample of depressed adolescents. Methods: Adolescent participants (aged 13-21 years) underwent a semistructured diagnostic interview and clinical assessment, which included the General Behavior Inventory Parent Version (P-GBI), a 73-item, parent-rated assessment of symptoms and behaviors. 1H-MRS scans of a left dorsolateral prefrontal cortex (L-DLPFC) voxel (8 cm3) were collected using a two-dimensional J-averaged sequence to assess N-acetylaspartate (NAA), Glu, Glx (glutamate + glutamine), and NAA/Glx concentrations. We used generalized linear models to assess the relationships between P-GBI scores and metabolite levels in L-DLPFC. Results: Thirty-six participants (17 healthy controls, 19 depressed) underwent 1H-MRS scans and clinical evaluation with the P-GBI. There was a significant negative relationship between P-GBI score and L-DLPFC NAA/Glx in the whole sample. However, the magnitude of the effect was small and statistical significance was lost after correcting for multiple comparisons. Conclusions: These preliminary results suggest that NAA/Glx may have utility as a marker of bipolar traits in healthy and depressed adolescents. If replicated, 1H-MRS measures of glutamatergic metabolism anomalies might have a role in identifying depressed adolescents at risk for mixed symptom presentations or BD. Identifying bipolarity in the early stages of the disease would have a significant impact on treatment planning and prognosis. Further longitudinal studies should examine neurochemical correlates of mood state during the developmental emergence of BD.

Characterizations of the lebesgue measure and product measures related to holomorphic functions having non-negative imaginary or real part

In this paper, we study a class of Borel measures on [Formula: see text] that arises as the class of representing measures of Herglotz-Nevanlinna functions. In particular, we study product measures within this class where products with the Lebesgue measures play a special role. Hence, we give several characterizations of the [Formula: see text]-dimensional Lebesgue measure among all such measures and characterize all product measures that appear in this class of measures. Furthermore, analogous results for the class of positive Borel measures on the unit poly-torus with vanishing mixed Fourier coefficients are also presented, and the relation between the two classes of measures with regard to the obtained results is discussed.

Dimensions of Two-Valued Sets via Imaginary Chaos

Abstract Two-valued sets are local sets of the 2D Gaussian free field (GFF) that can be thought of as representing all points of the domain that may be connected to the boundary by a curve on which the GFF takes values only in $[-a,b]$. Two-valued sets exist whenever $a+b\geq 2\lambda ,$ where $\lambda$ depends explicitly on the normalization of the GFF. We prove that the almost sure Hausdorff dimension of the two-valued set ${\mathbb{A}}_{-a,b}$ equals $d=2-2\lambda ^2/(a+b)^2$. For the key two-point estimate needed to give the lower bound on dimension, we use the real part of a “vertex field” built from the purely imaginary Gaussian multiplicative chaos. We also construct a non-trivial $d$-dimensional measure supported on ${\mathbb{A}}_{-a,b}$ and discuss its relation with the $d$-dimensional conformal Minkowski content of ${\mathbb{A}}_{-a,b}$.

Unraveling the Consequences of Childhood Maltreatment: Deviations From Typical Functional Neurodevelopment Mediate the Relationship Between Maltreatment History and Depressive Symptoms

BackgroundChildhood maltreatment is associated with lifelong psychiatric sequelae. However, our understanding of neurobiological mechanisms responsible for this association is limited. Childhood maltreatment may confer risk for psychopathology by altering neurodevelopmental trajectories during childhood and adolescence. Longitudinal research, which is essential for examining this question, has been limited. MethodsWe investigated maltreatment-associated alterations in the development of neural circuitry. Associations between cumulative childhood maltreatment (assessed using a dimensional measure of abuse and neglect via the Childhood Trauma Questionnaire) and the longitudinal development of resting-state functional connectivity (rsFC) were examined in 130 community-residing adolescents. Functional magnetic resonance imaging data were acquired at age 16 (T1; mean ± SD age, 16.46 ± 0.52 years; 66 females) and age 19 (T2; mean follow-up period, 2.35 years; n = 90 with functional magnetic resonance imaging data at both time points). ResultsWe found maltreatment to be associated with widespread longitudinal increases in rsFC, primarily between default mode, dorsal attention, and frontoparietal systems. We also found sex-dependent increased maltreatment-associated rsFC in male participants in salience and limbic circuits. Cross-sectional analyses revealed a shift in maltreatment-related rsFC alterations, which were localized to subcortical and sensory circuits at T1 and to frontal circuits at T2. Finally, longitudinal increases in rsFC connectivity mediated the relationship between childhood maltreatment and increased depressive symptoms. ConclusionsTo our knowledge, this is the first study to examine longitudinal maltreatment-related alterations in rsFC in adolescents. Our findings shed light on the neurodevelopmental consequences of childhood maltreatment and provide evidence for their role in risk for depression.

Regularity of area minimizing currents mod p

We establish a first general partial regularity theorem for area minimizing currents {mathrm{mod}}(p), for every p, in any dimension and codimension. More precisely, we prove that the Hausdorff dimension of the interior singular set of an m-dimensional area minimizing current {mathrm{mod}}(p) cannot be larger than m-1. Additionally, we show that, when p is odd, the interior singular set is (m-1)-rectifiable with locally finite (m-1)-dimensional measure.

Gene co-expression networks in peripheral blood capture dimensional measures of emotional and behavioral problems from the Child Behavior Checklist (CBCL)

The U.S. National Institute of Mental Health (NIMH) introduced the research domain criteria (RDoC) initiative to promote the integration of information across multiple units of analysis (i.e., brain circuits, physiology, behavior, self-reports) to better understand the basic dimensions of behavior and cognitive functioning underlying normal and abnormal mental conditions. Along those lines, this study examined the association between peripheral blood gene expression levels and emotional and behavioral problems in school-age children. Children were chosen from two age- and sex-matched groups: those with or without parental reports of any prior or current psychiatric diagnosis. RNA-sequencing was performed on whole blood from 96 probands aged 6–12 years who were medication-free at the time of assessment. Module eigengenes were derived using weighted gene co-expression network analysis (WGCNA). Associations were tested between module eigengene expression levels and eight syndrome scales from parent ratings on the Child Behavior Checklist (CBCL). Nine out of the 36 modules were significantly associated with at least one syndrome scale measured by the CBCL (i.e., aggression, social problems, attention problems, and/or thought problems) after accounting for covariates and correcting for multiple testing. Our study demonstrates that variation in peripheral blood gene expression relates to emotional and behavioral profiles in children. If replicated and validated, our results may help in identifying problem or at-risk behavior in pediatric populations, and in elucidating the biological pathways that modulate complex human behavior.

Test-retest reliability of DSM-5 substance disorder measures as assessed with the PRISM-5, a clinician-administered diagnostic interview

AimIn DSM-5, the definitions of substance use disorders (SUD) were changed considerably, yet little is known about the reliability of DSM-5 SUD and its new features. MethodsThe test-retest reliability of DSM-5 SUD and DSM-IV substance dependence (SD) was evaluated in 565 adult substance users, each interviewed twice by different clinician interviewers using the semi-structured Psychiatric Research Interview for Substance and Mental Disorders, DSM-5 version (PRISM-5). DSM-5 SUD and DSM-IV SD criteria were assessed for past year and lifetime, yielding diagnoses and severity levels for alcohol, tobacco, cannabis, cocaine, heroin, opioids, sedatives, hallucinogen, and stimulant use disorders. Cohen’s and intraclass correlation coefficients (ICC) assessed reliability for categorical and graded outcomes, respectively. Factors potentially influencing reliability were explored, including inpatient vs. community participant, days between interviews gender, age, race/ethnicity, and SUD severity. ResultsDSM-5 SUD diagnoses had substantial to excellent reliability for most substances (κ = 0.63−0.94), and moderate for others (hallucinogens, stimulants, sedatives; κ = 0.50−0.59). For graded outcomes (DSM-5 SUD mild, moderate, severe; criteria count 0–11), reliability was substantial to excellent (ICC = 0.74−0.99). Comparisons of DSM-5 SUD and DSM-IV SD reliability showed few significant differences. Reliability of the DSM-5 craving criterion was excellent for heroin (κ = 0.84−0.95) and moderate to substantial for other substances (κ = 0.49−0.76). The only factor influencing reliability of SUD was severity, with milder disorders significantly more likely to be discordant between the interviews. ConclusionReproducibility is crucial to good measurement. In a large sample using rigorous methodology, diagnoses and dimensional measures from clinician-administered interviews for DSM-5 SUD were generally highly reliable.

Transdiagnostic trajectories of irritability and oppositional, depression and anxiety problems from preschool to early adolescence

Irritability is a transdiagnostic symptom in oppositional defiant disorder, depression, and anxiety, all highly comorbid disorders but with unknown simultaneous evolution. The aim was to obtain the developmental trajectories of simultaneous irritability and oppositional, depression, and anxiety problems from preschool age to early adolescence. A sample of 493 community children was followed up annually from ages 3–11 years and assessed using categorical and dimensional measures answered by parents and teachers. Latent Class Growth Analysis for four parallel processes was used to identify distinct groups of individual trajectories for irritability and oppositional, depression, and anxiety problems. Outcomes at ages 11 and 12 were compared among trajectories using regression models and multiple comparisons. A 3-class model showed the highest entropy (0.961) and adequate posterior probabilities of class membership (≥0.969). Class 1 (n = 331, 67.1%) was made up of children with stable low scores in all the variables; class 2 (n = 55, 11.2%) of children with high depression, anxiety, and irritability and above the mean stable profiles for oppositional problems; and class 3 (n = 107, 21.7%) of children with medium-high increasing irritability and oppositional problems and on the mean depression and anxiety. The classes with symptomatology and irritability (2 and 3) clearly differed from class 1 (low) at baseline and in outcomes. The course of irritability and oppositional, depression, and anxiety problems from ages 3–11 years differed qualitatively and quantitatively across subgroups of children. The 3 classes identified may help to guide clinicians’ decision-making regarding treating irritability and its comorbid disorders.

Influence of process parameters on dimensional accuracy of machined Titanium (Ti-6Al-4V) alloy in Laser Beam Machining Process

The process enhancement plays a vital role in the modern machining techniques during machining of newer materials such as titanium alloys. In the present work, a research endeavor was made to examine the effects of process parameters in laser beam machining process while drilling holes over Titanium (Ti-6Al-4V) alloy under Taguchi approach of experiments. Nozzle distance, power, focal length and gas pressure were chosen as the input process parameters to assess the dimensional accuracy quality measures such as roundness and ovality in laser beam machining process. It was found that power has the most significant impact on determining the dimensional accuracy. 1.2 mm (ND), 2 mm (L), 4 bar (GP) and 2 kW (J) has been chosen as optimal process parameters combination for obtaining better dimensional accuracy among the selected process parameters. It was also observed that the machinability could be highly influenced with lower peak power.