Behavioral activation therapy for depression is associated with a reduction in the concentration of circulating quinolinic acid.

BACKGROUND: An inflammation-induced imbalance in the kynurenine pathway (KP) has been reported in major depressive disorder but the utility of these metabolites as predictive or therapeutic biomarkers of behavioral activation (BA) therapy is unknown. METHODS: Serum samples were provided by 56 depressed individuals before BA therapy and 29 of these individuals also provided samples after 10 weeks of therapy to measure cytokines and KP metabolites. The PROMIS Depression Scale (PROMIS-D) and the Sheehan Disability Scale were administered weekly and the Beck depression inventory was administered pre- and post-therapy. Data were analyzed with linear mixed-effect, general linear, and logistic regression models. The primary outcome for the biomarker analyses was the ratio of kynurenic acid to quinolinic acid (KynA/QA). RESULTS: BA decreased depression and disability scores (p's < 0.001, Cohen's d's > 0.5). KynA/QA significantly increased at post-therapy relative to baseline (p < 0.001, d = 2.2), an effect driven by a decrease in QA post-therapy (p < 0.001, uncorrected, d = 3.39). A trend towards a decrease in the ratio of kynurenine to tryptophan (KYN/TRP) was also observed (p = 0.054, uncorrected, d = 0.78). Neither the change in KynA/QA, nor baseline KynA/QA were associated with response to BA therapy. CONCLUSION: The current findings together with previous research show that electronconvulsive therapy, escitalopram, and ketamine decrease concentrations of the neurotoxin, QA, raise the possibility that a common therapeutic mechanism underlies diverse forms of anti-depressant treatment but future controlled studies are needed to test this hypothesis.

Striatal reactivity during emotion and reward relates to approach-avoidance conflict behaviour and is altered in adults with anxiety or depression.

BACKGROUND: We have previously reported activation in reward, salience and executive control regions during functional MRI (fMRI) using an approach-avoidance conflict (AAC) decision-making task with healthy adults. Further investigations into how anxiety and depressive disorders relate to differences in neural responses during AAC can inform their understanding and treatment. We tested the hypothesis that people with anxiety or depression have altered neural activation during AAC. METHODS: We compared 118 treatment-seeking adults with anxiety or depression and 58 healthy adults using linear mixed-effects models to examine group-level differences in neural activation (fMRI) during AAC decision-making. Correlational analyses examined relationships between behavioural and neural measures. RESULTS: Adults with anxiety or depression had greater striatal engagement when reacting to affective stimuli (p = 0.008, d = 0.31) regardless of valence, and weaker striatal engagement during reward feedback (p = 0.046, d = -0.27) regardless of the presence of monetary reward. They also had blunted amygdala activity during decision-making (p = 0.023, d = -0.32) regardless of the presence of conflict. Across groups, approach behaviour during conflict decision-making was inversely correlated with striatal activation during affective stimuli (p < 0.001, r = -0.28) and positively related to striatal activation during reward feedback (p < 0.001, r = 0.27). LIMITATIONS: Our transdiagnostic approach did not allow for comparisons between specific anxiety disorders, and our cross-sectional approach did not allow for causal inference. CONCLUSION: Anxiety and depression were associated with altered neural responses to AAC. Findings were consistent with the role of the striatum in action selection and reward responsivity, and they point toward striatal reactivity as a future treatment target. Blunting of amygdala activity in anxiety or depression may indicate a compensatory response to inhibit affective salience and maintain approach.

Spin Dynamics of (Sc[Formula: see text]Lu[Formula: see text])[Formula: see text]In Studied by Electron Spin Resonance.

The electron spin resonance (ESR) of conduction electrons is reported for the weak itinerant ferromagnet Sc[Formula: see text]In which, upon chemical substitution with Lu, shows a suppression of ferromagnetic correlations. A well-defined ESR lineshape of Dysonian type characterizes the spectra. The ESR linewidth, determined by the spin dynamics, displays a broad minimum only for the Sc[Formula: see text]In compound. We discuss the results using the mechanism of exchange enhancement of spin-lifetimes.

Modeling VI and VDRL feedback functions: Searching normative rules through computational simulation.

We present the mathematical description of feedback functions of variable interval and variable differential reinforcement of low rates as functions of schedule size only. These results were obtained using an R script named Beak, which was built to simulate rates of behavior interacting with simple schedules of reinforcement. Using Beak, we have simulated data that allow an assessment of different reinforcement feedback functions. This was made with unparalleled precision, as simulations provide huge samples of data and, more importantly, simulated behavior is not changed by the reinforcement it produces. Therefore, we can vary response rates systematically. We've compared different reinforcement feedback functions for random interval schedules, using the following criteria: meaning, precision, parsimony, and generality. Our results indicate that the best feedback function for the random interval schedule was published by Baum (1981). We also propose that the model used by Killeen (1975) is a viable feedback function for the random differential reinforcement of low rates schedule. We argue that Beak paves the way for greater understanding of schedules of reinforcement, addressing still open questions about quantitative features of simple schedules. Also, Beak could guide future experiments that use schedules as theoretical and methodological tools.

Rachlin's extended self: Influences on a Brazilian research group.

We pay tribute to Rachlin's work stating that researching and writing for posterity is an act of self-control and altruism. We show how Rachlin's work influenced a series of seminars at the University of São Paulo (Brazil) based on his book from 1989, Judgment, Decision, and Choice. This influence is illustrated through two empirical exercises conducted during our seminars, where students were actively involved in data collection and analysis. The first exercise is about judgment of randomness involving coin tossing. The second is a replication of a procedure by Jones and Rachlin (2006) about social discounting of monetary quantities. We use these empirical examples to highlight some of Rachlin's major contributions to the science of behavior and their implications to our seminars and to ourselves as researchers.

Amplification of Positivity Therapy for Co-occurring Alcohol Use Disorder with Depression and Anxiety Symptoms: Pilot Feasibility Study and Case Series.

Positive valence system dysregulation is a relatively unexplored transdiagnostic mechanism and potential treatment target underpinning alcohol use and anxiety and depression symptoms. The current study examined the feasibility and potential benefit of a behavioral intervention focused on amplification of positivity (AMP) with eight adults (five female) diagnosed with alcohol use disorder and clinically significant depression or anxiety (ClinicalTrials.gov: NCT04278365). AMP for alcohol use (AMP-A) was delivered in 11 individual sessions involving positive activity interventions integrated alongside psychoeducation and alcohol use monitoring. Case descriptions are provided to illustrate treatment implementation. Treatment credibility and acceptability, participant endorsement of the therapy, and homework compliance were rated moderate to high. Exploratory, intent-to-treat analyses suggested medium to large effect sizes for post-treatment improvements in alcohol use, depression, anxiety, and positive affect. Results provide initial evidence of feasibility and acceptability of AMP-A and will be useful for informing future randomized clinical trials to examine clinical efficacy.

P300 amplitude during a monetary incentive delay task predicts future therapy completion in individuals with major depressive disorder.

INTRODUCTION: Treatment effectiveness for major depressive disorder (MDD) is often affected by client non-adherence, dropout, and non-response. Identification of client characteristics predicting successful treatment completion and/or response (i.e., symptom reduction) may be an important tool to increase intervention effectiveness. It is unclear whether neural attenuations in reward processing associated with MDD predict behavioral treatment outcome. METHODS: This study aimed to determine whether blunted neural responses to reward at baseline differentiate MDD (n = 60; 41 with comorbid anxiety) and healthy control (HC; n = 40) groups; and predict MDD completion of and response to 7-10 sessions of behavior therapy. Participants completed a monetary incentive delay (MID) task. The N200, P300, contingent negative variation (CNV) event related potentials (ERPs) and behavioral responses (reaction time [RT], correct hits) were quantified and extracted for cross-sectional group analyses. ERPs and behavioral responses demonstrating group differences were then used to predict therapy completion and response within MDD. RESULTS: MDD exhibited faster RT and smaller P300 amplitudes than HC across conditions. Within the MDD group, treatment completers (n = 37) exhibited larger P300 amplitudes than non-completers (n = 21). LIMITATIONS: This study comprises secondary analyses of EEG data; thus task parameters are not optimized to examine feedback ERPs from the paradigm. We did not examine heterogenous presentations of MDD; however, severity and comorbidity did not influence findings. CONCLUSIONS: Previous studies suggest that P300 is an index of motivational salience and stimulus resource allocation. In sum, individuals who deploy greater neural resources to task demands are more likely to persevere in behavioral therapy.

A neural substrate for behavioral inhibition in the risk for major depressive disorder.

OBJECTIVE: Behavioral inhibition (BI) is an early developing trait associated with cautiousness and development of clinical depression and anxiety. Little is known about the neural basis of BI and its predictive importance concerning risk for internalizing disorders. We looked at functional connectivity of the default-mode network (DMN) and salience network (SN), given their respective roles in self-relational and threat processing, in the risk for internalizing disorders, with an emphasis on determining the functional significance of these networks for BI. METHOD: We used functional magnetic resonance imaging to scan, during the resting state, children and adolescents 8 to 17 years of age who were either at high familial risk (HR; n = 16) or low familial risk (LR; n = 18) for developing clinical depression and/or anxiety. Whole-brain DMN and SN functional connectivity were estimated for each participant and compared across groups. We also compared the LR and HR groups on levels of BI and anxiety, and incorporated these data into follow-up neurobehavioral correlation analyses. RESULTS: The HR group, relative to the LR group, showed significantly decreased DMN connectivity with the ventral striatum and bilateral sensorimotor cortices. Within the HR group, trait BI increased as DMN connectivity with the ventral striatum and sensorimotor cortex decreased. The HR and LR groups did not differ with respect to SN connectivity. CONCLUSION: Our findings show, in the risk for internalizing disorders, a negative functional relation between brain regions supporting self-relational processes and reward prediction. These findings represent a potential neural substrate for behavioral inhibition in the risk for clinical depression and anxiety.

Confiabilidad interna y validez de construccion logica de dos instrumentos para medir sintomatologia psicologica en una muestra clinica: el inventario de depresion de Beck y la lista de cotejo de sintomas - 36 / Internal reability and construct validity of two instruments to measure psycological symptoms in a clinical sample: Beck Depression inventory, and Symptom Check List - 36

El estudio evalúa la confiabilidad interna y la validez de construcción lógica del Inventario de Depresión de Beck (IBD) y de la Lista de Cotejo de Síntomas - 36 (LCS-36) en una muestra clinica de 300 personas. El índice de consistencia interna para el IDB fue .8948 y para la LCS-36 fue .9469. Los resultados sugieren la presencia de cuatro factores en el IDB: actitudes negativas, cognitivo -conductual, biológico y somático. Estos resultados apoyan que los factores del IDB en una muestra clínica y puertorriqueña son congruentes con las dimensio-nes que se establecen en la literatura como fundamentales para establecer la nosología de la depresión. Con la LCS-36 encontramos seis factores principales: depresión, hostilidad/sospecha, ansiedad fóbica, somatización, disturbios de pensamiento e impedimento funcional. Los factores en la LCS-36 son congruen-tes con las dimensiones informadas en la literatura, la cual apoya la estructura factorial de este instrumento. También se encontró una correlación alta y significativa (.74) entre el IDB y de la LCS-36. Los resultados obtenidos para el IDB y la LCS-36 son alentadores. Ambos instrumentos ofrecen información consistente y válida de los constructos que pretenden medir. Se discuten las limitaciones del estudio y las posibilidades para futuros estudios.