Causes and consequences of stress generation: Longitudinal associations of negative events, aggressive behaviors, rumination, and depressive symptoms.

The present study examined the causes and consequences of stress generation in university students in Japan. A two-wave longitudinal study with an 8- or 9-week interval was conducted in the fall of 2020. Undergraduate and graduate students at four universities in Japan (N = 201) completed self-report measures assessing experiences of negative interpersonal dependent events, negative non-interpersonal events, and negative independent events at two times. At the same time, they also responded to measures of aggressive behaviors, trait rumination, and depressive symptoms. Path analyses revealed that baseline aggressive behaviors were positively associated with an increase in subsequent negative interpersonal dependent events, even after controlling for the influences of negative interpersonal dependent events, rumination, and depressive symptoms at baseline. However, aggressive behaviors were not significantly associated with subsequent negative non-interpersonal dependent events or negative independent events. These findings suggest that aggressive behaviors may have been a factor leading to interpersonal stress generation. Furthermore, all categories of negative event experiences predicted an increase in subsequent depressive symptoms, but not subsequent rumination, and rumination was not significantly associated with subsequent depressive symptoms. This research extends previous studies on the causes and consequences of stress generation conducted in the US by using specific measures of aggressive behaviors and including a non-restricted sample of university students in Japan. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12144-022-02859-9.

Validation of brain-derived signals in near-infrared spectroscopy through multivoxel analysis of concurrent functional magnetic resonance imaging.

Near-infrared spectroscopy (NIRS) is a convenient and safe brain-mapping tool. However, its inevitable confounding with hemodynamic responses outside the brain, especially in the frontotemporal head, has questioned its validity. Some researchers attempted to validate NIRS signals through concurrent measurements with functional magnetic resonance imaging (fMRI), but, counterintuitively, NIRS signals rarely correlate with local fMRI signals in NIRS channels, although both mapping techniques should measure the same hemoglobin concentration. Here, we tested a novel hypothesis that different voxels within the scalp and the brain tissues might have substantially different hemoglobin absorption rates of near-infrared light, which might differentially contribute to NIRS signals across channels. Therefore, we newly applied a multivariate approach, a partial least squares regression, to explain NIRS signals with multivoxel information from fMRI within the brain and soft tissues in the head. We concurrently obtained fMRI and NIRS signals in 9 healthy human subjects engaging in an n-back task. The multivariate fMRI model was quite successfully able to predict the NIRS signals by cross-validation (interclass correlation coefficient = ∼0.85). This result confirmed that fMRI and NIRS surely measure the same hemoglobin concentration. Additional application of Monte-Carlo permutation tests confirmed that the model surely reflects temporal and spatial hemodynamic information, not random noise. After this thorough validation, we calculated the ratios of the contributions of the brain and soft-tissue hemodynamics to the NIRS signals, and found that the contribution ratios were quite different across different NIRS channels in reality, presumably because of the structural complexity of the frontotemporal regions. Hum Brain Mapp 38:5274-5291, 2017. © 2017 Wiley Periodicals, Inc.

Behavioral activation for late adolescents with subthreshold depression: a randomized controlled trial.

The main behavioral characteristic of subthreshold depression that is observed in adolescents is the low frequency of exposure to environmental rewards. Therefore, it was considered that a simple intervention conducted in short sessions, focusing on increasing access to positively reinforcing activities, would be efficacious in increasing the availability of rewards. We conduct a randomized controlled trial to examine the efficacy of such a behavioral activation program that was conducted weekly for 5 weeks in 60-min sessions. Late adolescent university students aged 18-19 years with subthreshold depression were randomly allocated to a treatment (n = 62) or a control group (n = 56). The primary outcome of the study was the Beck Depression Inventory-II score. Results indicated that late adolescent students in the treatment group showed significant improvements in their depressive symptoms (effect size -0.90, 95 % CI -1.28 to -0.51) compared to the control group. Students in the treatment group also showed significant improvements in self-reported rating of quality of life and in behavioral characteristics. It is concluded that this intervention had a large and significant effect despite being short and simple and that this low-intensity cognitive behavioral therapy program could be conducted in many different types of institutions. It is suggested that the long-term effects of the treatment program should be targeted for investigation in future studies.

Do Individuals with Alcohol Dependence Show Higher Unfairness Sensitivity? The Relationship Between Impulsivity and Unfairness Sensitivity in Alcohol-Dependent Adults.

BACKGROUND: Alcohol-dependent patients are known to be generally more unfairness sensitive. The ultimatum game (UG) is an experimental task designed to provoke feelings of perceived unfairness. A previous study using the UG has reported more unfairness sensitivity in patients with alcohol dependence than in a nondependent control group; it has been speculated that this increased sensitivity might be due to a difficulty in impulse control. However, the mechanism of this relationship has not been clarified. Therefore, the relationship between unfairness sensitivity in interpersonal relationships and impulsivity was investigated using UG and delay discounting (DD) paradigms. METHODS: Subjects were 32 individuals with alcohol dependency and 36 healthy control individuals; both groups performed UG and DD tasks. RESULTS: Participants with alcohol dependence rejected monetary offers deemed unfair at a significantly higher rate than did control participants. Moreover, the proportion of accepting unfairness was negatively correlated with impulsivity in patients with alcohol dependence. CONCLUSIONS: Perceived unfairness is related to impulsivity in patients with alcohol dependence. These results provide insights concerning the psychopathology of alcohol dependence.

[Brain mechanisms of depression--preliminary evidence from fMRI studies].

Although brain monoamines serotonin, noradrenaline, and dopamine have been repeatedly shown to be linked to depression, it remains unclear how monoamine dysfunction is mechanistically related to symptoms of depression. We hypothesized that imbalances in the networks of regions innervated by monoamines disrupt patients' learning and decision-making abilities, and this disruption could, in turn, lead to symptoms of depression. We have conducted functional magnetic resonance imaging (fMRI) studies on learning and decision-making, mainly focusing on the role of serotonin. Our results suggest that parallel organization for reward prediction at different time scales in the striatum is under differential modulation by serotonin, and that depression is associated with a diminished recruitment of the dorsal striatum, involved in long-term reward prediction. Based on these findings, the brain mechanisms of depression are discussed.

Preliminary assessment of the behavioral activation model in Japanese undergraduate students.

Many studies have reported that behavioral activation is an effective intervention for depression. The behavioral activation model is based on several formulations. For example, depressive mood leads to avoidant behaviors, avoidance negatively affects social contacts, decreased socialization lessens opportunities for positive reinforcement, and a decrease in positive reinforcement results in more depressive mood. The purpose of this study was to examine relationships among avoidant behavior, social contact, frequency of positive reinforcement, and depressive mood by using structural equation modeling to assess support for aspects of this behavioral activation model. Participants were 630 Japanese undergraduate students and vocational school students. Results provided preliminary support for the model. Treating both avoidance and activating behavior might contribute to decreased impairment.

Dismantling cognitive-behavioural therapy components for attention-deficit hyperactivity disorder in adolescents and adults: protocol for a network meta-analysis.

INTRODUCTION: Cognitive-behavioural therapy (CBT) consists of multiple treatment techniques for each treatment model and is tailored to the patient's characteristics. Randomised controlled trials (RCTs) have reported that CBT is effective for attention-deficit/hyperactivity disorder (ADHD); however, which CBT components are effective is unknown. In order to provide the best treatment technique, it is important to know which therapeutic component or combination thereof is more effective and what the specific effect size is. METHODS AND ANALYSIS: We will perform component network meta-analysis (cNMA). The search will include studies published from database inception up to 31 March 2022, in English. The electronic databases of MEDLINE (via PubMed), EMBASE, PsycINFO, ClinicalTrials.gov and Cochrane Library will be searched. We will systematically identify all RCTs in the treatment of ADHD between the ages of 10 and 60 years, comparing interventions composed of various CBT components with controlled interventions. We will perform pairwise and network meta-analysis with random effects to estimate summary ORs and standardised mean differences. We will assess the risk of bias in selected studies using the Cochrane risk of bias tool. ETHICS AND DISSEMINATION: Since we will review published papers, ethical approval is not required. The results from this cNMA will provide a panorama of the CBT-based ADHD studies. The results of this study will be published in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42022323898.

Neural and personality correlates of individual differences related to the effects of acute tryptophan depletion on future reward evaluation.

BACKGROUND/AIMS: In general, humans tend to discount the value of delayed reward. An increase in the rate of discounting leads to an inability to select a delayed reward over a smaller immediate reward (reward-delay impulsivity). Although deficits in the serotonergic system are implicated in this reward-delay impulsivity, there is individual variation in response to serotonin depletion. The aim of the present study was to investigate whether the effects of serotonin depletion on the ability to evaluate future reward are affected by individual personality traits or brain activation. METHODS: Personality traits were assessed using the NEO-Five Factor Inventory and Temperament and Character Inventory. The central serotonergic levels of 16 healthy volunteers were manipulated by dietary tryptophan depletion. Subjects performed a delayed reward choice task that required the continuous estimation of reward value during functional magnetic resonance imaging scanning. RESULTS: Discounting rates were increased in 9 participants, but were unchanged or decreased in 7 participants in response to tryptophan depletion. Participants whose discounting rate was increased by tryptophan depletion had significantly higher neuroticism and lower self-directedness. Furthermore, tryptophan depletion differentially affected the groups in terms of hemodynamic responses to the value of predicted future reward in the right insula. CONCLUSIONS: These results suggest that individuals who have high neuroticism and low self-directedness as personality traits are particularly vulnerable to the effect of low serotonin on future reward evaluation accompanied by altered brain activation patterns.

Sex differences in neural activation to ambiguous facial expression in happy and sad context.

Functional magnetic resonance imaging (fMRI) was used to investigate brain activation associated with a facial expression identification task (stimuli were full emotional, half emotional, or ambiguous in both happy and sad context) in 10 men and 10 women, fMRI assessment revealed significant interaction of sex x context in the right putamen for the ambiguous faces. Women showed a greater BOLD response to ambiguous facial expression in the sad context than in the happy context, while men showed a greater response in the happy context. Further, women showed a greater BOLD response than did men to ambiguous facial expression in the sad context, while men showed a greater response than women in the happy context. These results suggest that sad and happy context differentially modulate right putamen activation related to processing of ambiguous facial expression in men and women.

Metacognitive Ability and the Precision of Confidence.

In prior research, signal detection theory (SDT) has been widely utilized to assess metacognitive ability. However, the SDT metacognitive model requires the use of a two-alternative forced-choice task, while confidence must also be measured discretely. In our model, participants' cognitive ability and their confidence in the cognitive task were used to estimate their metacognitive abilities. Therefore, in this study, a metacognitive model that can be applied to various cognitive tasks was developed. This model implements the item response theory (IRT) and Q-learning models to estimate cognitive ability; participants' metacognitive ability is defined as the discrepancy between their confidence in their cognitive ability and their actual cognitive ability. The entire procedure was divided into two experiments. In experiment 1, two different cognitive tasks were used to estimate metacognitive ability and to examine overall discriminative and convergent validity. Notably, the parameters representing metacognitive ability did not correlate with cognitive ability but were positively correlated between the two tasks. In experiment 2, we performed a similar analysis using a different task to test the replicability of experiment 1. The results for experiment 2 were replicated for discriminative and convergent validity, albeit with weak results. Our metacognitive model exhibited high interpretability and versatility.