95 research outputs found
Implications of the mild gas motion found with Hitomi in the core of the Perseus cluster
Based mainly on X-ray observations, studies are made on interactions between
the intra-cluster medium (ICM) in clusters of galaxies and their member
galaxies. Through (magneto)hydrodynamic and gravitational channels, the moving
galaxies are expected to drag the ICM around them, and transfer to the ICM some
fraction of their dynamical energies on cosmological time scales. This
hypothesis is in line with several observations, including the possible
cosmological infall of galaxies towards the cluster center, found over
redshifts of z~1 to z~0. Further assuming that the energy lost by the galaxies
is first converted into ICM turbulence and then dissipated, this picture can
explain the subsonic and uniform ICM turbulence, measured with Hitomi in the
core region of the Perseus cluster. The scenario may also explain several other
unanswered problems regarding clusters of galaxies, including what prevents the
ICM from the expected radiative cooling, how the various mass components in
nearby clusters have attained different radial distributions, and how a thermal
stability is realized between hot and cool ICM components that co-exist around
cD galaxies. This view is also considered to pertain to the general scenario of
galaxy evolution, including their environmental effects.Comment: 15 pages, 3 figures, accepted for publication in A&
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Neural correlates for intrinsic motivational deficits of schizophrenia; implication for therapeutics of cognitive impairment
The ultimate goal of the treatment of schizophrenia is recovery, a notion related to improvement of cognitive and social functioning. Cognitive remediation therapies (CRT), one of the most effective cognition enhancing methods, have been shown to moderately improve social functioning. For this purpose, intrinsic motivation, related to internal values such as interest and enjoyment, has been shown to play a key role. Although the impairment of intrinsic motivation is one of the characteristics of schizophrenia, its neural mechanisms remain unclear. This is related to the lack of feasible measures of intrinsic motivation, and its response to treatment. According to the self-determination theory (SDT), not only intrinsic motivation, but extrinsic motivation has been reported to enhance learning and memory in healthy subjects to some extent. This finding suggests the contribution of different types of motivation to potentiate the ability of the CRT to treat cognitive impairment of schizophrenia. In this paper, we provide a review of psychological characteristics, assessment methods, and neural correlates of intrinsic motivation in healthy subjects and patients with schizophrenia. Particularly, we focus on neuroimaging studies of intrinsic motivation, including our own. These considerations are relevant to enhancement of functional outcomes of schizophrenia
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Social equality in the number of choice options is represented in the ventromedial prefrontal cortex
A distinct aspect of the sense of fairness in humans is that we care not only about equality in material rewards but also about equality in non-material values. One such value is the opportunity to choose freely among many options, often regarded as a fundamental right to economic freedom. In modern developed societies, equal opportunities in work, living, and lifestyle are enforced by anti-discrimination laws. Despite the widespread endorsement of equal opportunity, no studies have explored how people assign value to it. We used functional magnetic resonance imaging to identify the neural substrates for subjective valuation of equality in choice opportunity. Participants performed a two-person choice task in which the number of choices available was varied across trials independently of choice outcomes. By using this procedure, we manipulated the degree of equality in choice opportunity between players and dissociated it from the value of reward outcomes and their equality. We found that activation in the ventromedial prefrontal cortex tracked the degree to which the number of options between the two players was equal. In contrast, activation in the ventral striatum tracked the number of options available to participants themselves but not the equality between players. Our results demonstrate that the vmPFC, a key brain region previously implicated in the processing of social values, is also involved in valuation of equality in choice opportunity between individuals. These findings may provide valuable insight into the human ability to value equal opportunity, a characteristic long emphasized in politics, economics, and philosophy
Perspectives on childhood coronavirus disease vaccination in Japan and influencing factors
BACKGROUND: To support parental decision-making it is important to understand parents' perspectives on vaccination for their children and the factors that contribute to their vaccine hesitancy. There have been relatively few studies in this area in Japan, particularly with longitudinal and mixed methodologies. METHODS: We used an explanatory sequential mixed methods approach to describe longitudinal changes in vaccine acceptance and to explore factors associated with parental coronavirus 2019 (COVID-19) vaccine hesitancy. We recruited parents who had children aged 6 months to 11 years old from five facilities in Japan. Two cross-sectional online surveys and semi-structured online interviews were conducted. Logistic regression analysis was used to explore factors associated with parents' vaccine hesitancy for their children, and thematic analysis was used to analyze the interview data. RESULTS: In total, 134 parents responded to both online surveys and, of those, 10 participated in interviews. Acceptance rates of COVID-19 vaccination for their children were 19.4% (26/134) at the first survey and 11.2% (15/134) at the second survey. Integration of the data identified that the main factors for vaccine hesitancy included vaccine safety, vaccine effectiveness, government policy, and recommendations from people close to parents. CONCLUSIONS: Readily available and more balanced information, and community-wide support from people close to parents and familiar health-care providers are likely to provide better support for parents' decision-making. Further investigation is required on how to provide information in an easily understood manner
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Motivated with joy or anxiety: does approach-avoidance goal framing elicit differential reward-network activation in the brain?
Psychological research on human motivation repeatedly observed that approach goals (i.e., goals to attain success) increase task enjoyment and intrinsic motivation more strongly than avoidance goals (i.e., goals to avoid failure). The present study sought to address how the reward network in the brain-including the striatum and ventromedial prefrontal cortex-is involved when individuals engage in the same task with a focus on approach or avoidance goals. Participants reported stronger positive emotions when they focused on approach goals, but stronger anxiety and disappointment when they focused on avoidance goals. The fMRI analyses revealed that the reward network in the brain showed similar levels of activity to cues predictive of approach and avoidance goals. In contrast, the two goal states were associated with different patterns of activity in the visual cortex, hippocampus, and cerebellum during success and failure outcomes. Representation similarity analysis further revealed shared and different representations within the striatum and vmPFC between the approach and avoidance goal states, suggesting both the similarity and uniqueness of the mechanisms behind the two goal states. In addition, the distinct patterns of activation in the striatum were associated with distinct subjective experiences participants reported between the approach and the avoidance conditions. These results suggest the importance of examining the pattern of striatal activity in understanding the mechanisms behind different motivational states in humans
Social Cognition Deficits as a Target of Early Intervention for Psychoses: A Systematic Review
Backgrounds: Social cognition deficits are a core feature of schizophrenia and deteriorate functionality of patients. However, evidence is sparse for the treatment effect on social cognition impairments in the early stage of psychosis. Here, we provide a systematic review of the literature on social cognitive impairment in early psychosis in relation to its intervention.Methods: A literature search was conducted on English articles identified by Web of Science and PubMed databases, according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement.Results: Five papers met the inclusion criteria. Results from two studies of cognitive training and one study of modafinil indicate positive results regarding social cognition outcomes in patients with early psychosis. On the other hand, two studies with oxytocin and modafinil did not suggest such effects.Conclusions: Further research is warranted to explore the benefit of early intervention into disturbances of social cognition in psychoses
Effect of aspirin treatment on serum levels of lipoprotein (a) : analysis from the apolipoprotein (a) isoforms
We have found that aspirin lowers elevated serum lipoprotein(a) [Lp(a)] levels via reduction of the transcriptional activity of apolipoprotein(a) [apo(a)] gene with suppression of apo(a) mRNA expression. In the present study, we evaluated the effect of aspirin treatment on serum Lp(a) level and analyzed its relation to type of apo(a) isoform. Serum levels of Lp(a) were measured by turbidimetric immunoassay before and after the oral administration of aspirin therapy (81 mg/day) in 57 patients with coronary artery disease or cerebral infarction. Apo(a) isoforms were determined by immunoblotting method. In patients with high serum Lp(a) levels (more than 30 mg/dl), aspirin reduced serum Lp(a) levels to approximately 80 % of the baseline after one month. Their levels sustained significantly low even after six months. The effect of aspirin in reducing elevated serum Lp(a) levels were stronger in patients with smaller-sized type or double-band type of apo(a) isoforms. The transcriptional efficiency of apo(a) gene is thought to be increased in patients with these apo(a) isoforms. Therefore, these findings suggest that aspirin reduces apo(a) gene transcription preferentialy in patients with high transcriptional efficiency of this gene
Multifaceted Assessment of Chronic Gastritis: A Study of Correlations between Serological, Endoscopic, and Histological Diagnostics
Aim. Chronic gastritis was assessed serologically, endoscopically and histologically to identify correlations between these methods. Methods. Subjects comprised 319 patients who had provided informed consent. Serological assessment of chronic gastritis was based on the pepsinogen test method. Endoscopic gastritis and histological gastritis were assessed and scored according to the Kimura-Takemoto classification system and the updated Sydney classification system respectively, and correlations between these three methods were studied. Results. Pepsinogen I/II ratio showed a significant correlation to the extent of mononuclear cell infiltration of the gastric corpus. When histological gastritis was divided, on the basis of the distribution of mononuclear cell infiltration, into gastritis limited to the antrum and corpus gastritis, these types were distinguished with high accuracy using a pepsinogen I/II ratio of 3 as the cutoff. A good correlation was also seen between pepsinogen I/II ratio and development of atrophy in endoscopic gastritis, where groups with and without advanced atrophy were also distinguished with high accuracy using a cutoff value of 3. Conclusion. Significant correlations exist between serum pepsinogen levels, endoscopic gastritis, and histological gastritis. Pepsinogen I/II ratio allows prediction of the existence of endoscopic gastritis and histological gastritis, or the extent of their development, with high accuracy
Effects of behavioural activation on the neural circuit related to intrinsic motivation
[Background] Behavioural activation is an efficient treatment for depression and can improve intrinsic motivation. Previous studies have revealed that the frontostriatal circuit is involved in intrinsic motivation; however, there are no data on how behavioural activation affects the frontostriatal circuit.
[Aims] We aimed to investigate behavioural activation-related changes in the frontostriatal circuit.
[Method] Fifty-nine individuals with subthreshold depression were randomly assigned to either the intervention or non-intervention group. The intervention group received five weekly behavioural activation sessions. The participants underwent functional magnetic resonance imaging scanning on two separate occasions while performing a stopwatch task based on intrinsic motivation. We investigated changes in neural activity and functional connectivity after behavioural activation.
[Results] After behavioural activation, the intervention group had increased activation and connectivity in the frontostriatal region compared with the non-intervention group. The increased activation in the right middle frontal gyrus was correlated with an improvement of subjective sensitivity to environmental rewards.
[Conclusions] Behavioural activation-related changes to the frontostriatal circuit advance our understanding of psychotherapy-induced improvements in the neural basis of intrinsic motivation.
[Declaration of interest] None.This work was supported by a Grant-in-Aid for Scientific Research on Innovative Areas from Japan Society for the Promotion of Science, JSPS (grants 16H06395 and 16H06399), and grant 23118004 from the Ministry of Education, Culture, Sports, Science and Technology, Japan. This work was partially supported by the programme for Brain Mapping by Integrated Neurotechnologies for Disease Studies (Brain/MINDS) by Japan Agency for Medical Research and Development, AMED (grant 15dm0207012h0002) and Integrated Research on Depression, Dementia and Development Disorders by AMED (grant 16dm0107093h0001).
The funders had no role in the design and conduct of the study; collection, management, analysis and interpretation of the data; preparation or review of the manuscript or decision to submit the manuscript for publication
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