scholarly journals Extensive brain structural heterogeneity in individuals with schizophrenia and bipolar disorder

2020 ◽  
Author(s):  
Thomas Wolfers ◽  
Jaroslav Rokicki ◽  
Dag Alnæs ◽  
Ingrid Agartz ◽  
Seyed Mostafa Kia ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Gaussian Process Regression ◽  
Structural Heterogeneity ◽  
Brain Regions ◽  
Individual Heterogeneity ◽  
Group Level ◽  
Healthy Individuals ◽  
Voxel Based Morphometry ◽  
Structural Aberrations ◽  
The Individual

ABSTRACTIdentifying brain processes involved in the risk and development of mental disorders is a major aim. We recently reported substantial inter-individual heterogeneity in brain structural aberrations among patients with schizophrenia and bipolar disorder. Estimating the normative range of voxel-based morphometry (VBM) data among healthy individuals using a Gaussian Process Regression (GPR) enables us to map individual deviations from the healthy range in unseen datasets. Here we aim to replicate our previous results in an independent sample of patients with schizophrenia (n=166), bipolar disorder (n=135) and healthy individuals (n=687). In line with previous findings, our results revealed robust group level differences between patients and healthy controls, yet only a small proportion of patients with schizophrenia or bipolar disorder exhibited extreme negative deviations from the norm in the same brain regions. These direct replications support that group level-differences in brain structure disguise considerable individual differences in brain aberrations, with important implications for the interpretation and generalization of group-level brain imaging findings to the individual with a mental disorder.

scholarly journals Comparison of subtyping methods for neuroimaging studies in Alzheimer’s disease: a call for harmonization

2020 ◽  
Author(s):  
Rosaleena Mohanty ◽  
Gustav Mårtensson ◽  
Konstantinos Poulakis ◽  
J-Sebastian Muehlboeck ◽  
Elena Rodriguez-Vieitez ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Amyloid Beta ◽  
Reference Group ◽  
Group Level ◽  
Healthy Individuals ◽  
Individual Level ◽  
Dementia Patients ◽  
Tau Pet ◽  
The Individual

Abstract Biological subtypes in Alzheimer’s disease, originally identified on neuropathological data, have been translated to in vivo biomarkers such as structural magnetic resonance imaging (sMRI) and positron emission tomography (PET), to disentangle the heterogeneity within Alzheimer’s disease. Although there is methodological variability across studies, comparable characteristics of subtypes are reported at the group level. In this study, we investigated whether group-level similarities translate to individual-level agreement across subtyping methods, in a head-to-head context. We compared five previously published subtyping methods. Firstly, we validated the subtyping methods in 89 amyloid-beta positive Alzheimer’s disease dementia patients (reference group: 70 amyloid-beta negative healthy individuals) using sMRI. Secondly, we extended and applied the subtyping methods to 53 amyloid-beta positive prodromal Alzheimer’s disease and 30 amyloid-beta positive Alzheimer’s disease dementia patients (reference group: 200 amyloid-beta negative healthy individuals) using sMRI and tau PET. Subtyping methods were implemented as outlined in each original study. Group-level and individual-level comparisons across methods were performed. Each individual subtyping method was replicated, and the proof-of-concept was established. At the group level, all methods captured subtypes with similar patterns of demographic and clinical characteristics, and with similar cortical thinning and tau PET uptake patterns. However, at the individual level large disagreements were found in subtype assignments. Although characteristics of subtypes are comparable at the group level, there is a large disagreement at the individual level across subtyping methods. Therefore, there is an urgent need for consensus and harmonization across subtyping methods. We call for establishment of an open benchmarking framework to overcome this problem.

QUALITY OF INDIVIDUAL AND GROUP LEVEL INTERVENTIONS FOR FIRST EPISODE PSYCHOSIS AT THE TERTIARY PSYCHIATRIC HOSPITAL IN UGANDA.

2020 ◽  
Author(s):  
Emmanuel Kiiza Mwesiga ◽  
Noeline Nakasujja ◽  
Lawrence Nankaba ◽  
Juliet Nakku ◽  
Seggane Musisi
Keyword(s):  
Psychiatric Hospital ◽  
Psychotic Disorders ◽  
First Episode Psychosis ◽  
First Episode ◽  
Group Level ◽  
Group Interventions ◽  
Episode Psychosis ◽  
Essential Components ◽  
The Individual

Introduction: Individual and group level interventions have the largest effect on outcomes in patients with the first episode of psychosis. The quality of these individual and group level interventions provided to first-episode psychosis patients in Uganda is unclear.Methods: The study was performed at Butabika National Psychiatric Teaching and referral hospital in Uganda. A retrospective chart review of recently discharged adult in-patients with the first episode of psychosis was first performed to determine the proportion of participants who received the different essential components for individual and group level interventions. From the different proportions, the quality of the services across the individual and group interventions was determined using the first-Episode Psychosis Services Fidelity Scale (FEPS-FS). The FEPS-FS assigns a grade of 1-5 on a Likert scale depending on the proportion of patients received the different components of the intervention. Results: The final sample included 156 first-episode psychosis patients. The median age was 27 years [IOR (24-36)] with 55% of participants of the female gender. 13 essential components across the individual and group interventions were assessed and their quality quantified. All 13 essential components had poor quality with the range of scores on the FEPS-FS of 1-3. Only one essential component assessed (use of single antipsychotics) had moderate quality.Discussion: Among current services at the National psychiatric hospital of Uganda, the essential for individual and group level interventions for psychotic disorders are of low quality. Further studies are required on how the quality of these interventions can be improved.

Reply to Connor and Evers (2020): Critique of the Bias of Crowds Model Simply Restates the Model

2020 ◽  
Author(s):  
Keith Payne ◽  
Heidi A. Vuletich ◽  
Kristjen B. Lundberg
Keyword(s):  
Implicit Bias ◽  
Group Level ◽  
Systemic Racism ◽  
Individual Level ◽  
The Core ◽  
Psychological Science ◽  
Implicit Biases ◽  
The Individual

The Bias of Crowds model (Payne, Vuletich, & Lundberg, 2017) argues that implicit bias varies across individuals and across contexts. It is unreliable and weakly associated with behavior at the individual level. But when aggregated to measure context-level effects, the scores become stable and predictive of group-level outcomes. We concluded that the statistical benefits of aggregation are so powerful that researchers should reconceptualize implicit bias as a feature of contexts, and ask new questions about how implicit biases relate to systemic racism. Connor and Evers (2020) critiqued the model, but their critique simply restates the core claims of the model. They agreed that implicit bias varies across individuals and across contexts; that it is unreliable and weakly associated with behavior at the individual level; and that aggregating scores to measure context-level effects makes them more stable and predictive of group-level outcomes. Connor and Evers concluded that implicit bias should be considered to really be noisily measured individual construct because the effects of aggregation are merely statistical. We respond to their specific arguments and then discuss what it means to really be a feature of persons versus situations, and multilevel measurement and theory in psychological science more broadly.

The Epistemology of Groups

2020 ◽  
Author(s):  
Jennifer Lackey
Keyword(s):  
Group Level ◽  
Social Significance ◽  
Individual Group ◽  
Key Concepts ◽  
Normative Requirements ◽  
Group Members ◽  
The Individual ◽  
Belief Justification ◽  
In Virtue Of ◽  
Trump Administration

Groups are often said to bear responsibility for their actions, many of which have enormous moral, legal, and social significance. The Trump Administration, for instance, is said to be responsible for the U.S.’s inept and deceptive handling of COVID-19 and the harms that American citizens have suffered as a result. But are groups subject to normative assessment simply in virtue of their individual members being so, or are they somehow agents in their own right? Answering this question depends on understanding key concepts in the epistemology of groups, as we cannot hold the Trump Administration responsible without first determining what it believed, knew, and said. Deflationary theorists hold that group phenomena can be understood entirely in terms of individual members and their states. Inflationary theorists maintain that group phenomena are importantly over and above, or otherwise distinct from, individual members and their states. It is argued that neither approach is satisfactory. Groups are more than their members, but not because they have “minds of their own,” as the inflationists hold. Instead, this book shows how group phenomena—like belief, justification, and knowledge—depend on what the individual group members do or are capable of doing while being subject to group-level normative requirements. This framework, it is argued, allows for the correct distribution of responsibility across groups and their individual members.

scholarly journals Examining the Effects of Three Group-Level Metacognitive Scaffoldings on In-Service Teachers’ Knowledge Building

2021 ◽  
pp. 073563312110308
Author(s):  
Fan Ouyang ◽  
Si Chen ◽  
Yuqin Yang ◽  
Yunqing Chen
Keyword(s):  
Small Groups ◽  
Mixed Method ◽  
Peer Interactions ◽  
Knowledge Building ◽  
Group Level ◽  
Question Asking ◽  
Individual Level ◽  
The Individual ◽  
Task Oriented ◽  
Metacognitive Scaffolding

Group-level metacognitive scaffolding is critical for productive knowledge building. However, previous research mainly focuses on the individual-level metacognitive scaffoldings in helping learners improve knowledge building, and little effort has been made to develop group-level metacognitive scaffolding (GMS) for knowledge building. This research designed three group-level metacognitive scaffoldings of general, task-oriented, and idea-oriented scaffoldings to facilitate in-service teachers’ knowledge building in small groups. A mixed method is used to examine the effects of the GMSs on groups’ knowledge building processes, performances, and perceptions. Results indicate a complication of the effects of GMSs on knowledge building. The idea-oriented scaffolding has potential to facilitate question-asking and perspective-proposing inquiry through peer interactions; the general scaffolding does not necessarily lessen teachers’ idea-centered explanation and elaboration on the individual level; the task-oriented scaffolding has the worst effect. Pedagogical and research implications are discussed to foster knowledge building with the support of GMSs.

scholarly journals Replicating extensive brain structural heterogeneity in individuals with schizophrenia and bipolar disorder

2021 ◽  
Author(s):  
Thomas Wolfers ◽  
Jaroslav Rokicki ◽  
Dag Alnæs ◽  
Pierre Berthet ◽  
Ingrid Agartz ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Structural Heterogeneity

scholarly journals Comparative physical activity as a global question to assess physical activity among university students

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Katharina Diehl ◽  
Alessia Brassat ◽  
Jennifer Hilger-Kolb
Keyword(s):  
Physical Activity ◽  
University Students ◽  
Online Survey ◽  
Group Level ◽  
Comparative Measurement ◽  
Cross Sectional ◽  
Physically Active ◽  
Comparative Optimism ◽  
Individual Assessment ◽  
The Individual

Abstract Background To assess physical activity (PA), a comparative measurement – evaluating one’s own PA compared to others – may be an appropriate method. In previous studies, the use of comparative measurements led to an effect known as unrealistic comparative optimism (UCO) – people being unrealistically optimistic about their behavior. Our aim was to use this comparative measurement in university students to quantify the prevalence of UCO at the group level and to draw conclusions on its validity. Methods We used data from the Nutrition and Physical Activity in Adolescence Study (NuPhA), a cross-sectional online survey that included only self-reports (n = 689). To assess PA among students, they were asked to rate their PA level compared to that of their same-aged fellow students. In addition, we used the Godin-Shephard leisure-time PA questionnaire and other questions on PA for comparisons. We used bivariate and cluster-based analyses to identify potential UCO. Results We found that UCO at the group level led to an uneven distribution, with a higher proportion of students who rated themselves as being more physically active than average. However, the individual assessment of PA with a single and simple comparative question seemed to be valid. Discussion A global single comparative question seems useful for studies where PA is measured as a covariate in university students.

scholarly journals A Risk Calculator to Predict the Individual Risk of Conversion From Subthreshold Bipolar Symptoms to Bipolar Disorder I or II in Youth

2018 ◽  
Vol 57 (10) ◽  
pp. 755-763.e4 ◽  
Author(s):  
Boris Birmaher ◽  
John A. Merranko ◽  
Tina R. Goldstein ◽  
Mary Kay Gill ◽  
Benjamin I. Goldstein ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Individual Risk ◽  
Risk Calculator ◽  
The Individual

Thirty-year cardiovascular risk score in patients with newly diagnosed bipolar disorder and their unaffected first-degree relatives

2018 ◽  
Vol 53 (7) ◽  
pp. 651-662 ◽  
Author(s):  
Klara Coello ◽  
Hanne L Kjærstad ◽  
Sharleny Stanislaus ◽  
Sigurd Melbye ◽  
Maria Faurholt-Jepsen ◽  
...  
Keyword(s):  
Cardiovascular Disease ◽  
Bipolar Disorder ◽  
Cardiovascular Risk ◽  
Risk Score ◽  
Disease Risk ◽  
Cardiovascular Disease Risk ◽  
Newly Diagnosed ◽  
Healthy Individuals ◽  
First Degree Relatives ◽  
Age And Sex

Objectives: Bipolar disorder is associated with a decreased life expectancy of 8–12 years. Cardiovascular disease is the leading cause of excess mortality. For the first time, we investigated the Framingham 30-year risk score of cardiovascular disease in patients with newly diagnosed/first-episode bipolar disorder, their unaffected first-degree relatives and healthy individuals. Methods: In a cross-sectional study, we compared the Framingham 30-year risk score of cardiovascular disease in 221 patients with newly diagnosed/first-episode bipolar disorder, 50 of their unaffected first-degree relatives and 119 healthy age- and sex-matched individuals with no personal or first-degree family history of affective disorder. Among patients with bipolar disorder, we further investigated medication- and illness-related variables associated with cardiovascular risk. Results: The 30-year risk of cardiovascular disease was 98.5% higher in patients with bipolar disorder ( p = 0.017) and 85.4% higher in unaffected first-degree relatives ( p = 0.042) compared with healthy individuals in models adjusted for age and sex. When categorizing participants in low cardiovascular risk without considering age and sex distribution among participants, 81% of patients were at low risk, versus 92% of unaffected relatives and 89% of healthy individuals. Of the patients 209 (94.6%) were diagnosed within the preceding 2 years. Smoking was more prevalent among patients with bipolar disorder (45.2%) and their unaffected first-degree relatives (20.4%) compared with healthy individuals (12.8%). Similarly, dyslipidemia was more common among patients with bipolar disorder compared with healthy individuals. Treatment with psychotropic medication with metabolic adverse effects was associated with higher 30-year cardiovascular disease risk score, whereas we did not find illness-related variables associated with cardiovascular risk among patients with bipolar disorder. Conclusion: We found an enhanced cardiovascular disease risk score in patients with newly diagnosed bipolar disorder and their unaffected first-degree relatives, which points to a need for specific primary preventive interventions against smoking and dyslipidemia in these populations.

scholarly journals Neuroanatomical Correlates of Impulsive Choices and Risky Decision Making in Young Chronic Tobacco Smokers: A Voxel-Based Morphometry Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Aldo Alberto Conti ◽  
Alexander Mario Baldacchino
Keyword(s):  
Decision Making ◽  
Smoking Behavior ◽  
Smoking Initiation ◽  
Brain Regions ◽  
Anterior Cingulate ◽  
Risky Decision Making ◽  
Voxel Based Morphometry ◽  
Tobacco Exposure ◽  
Risky Decision ◽  
Cognitive Impulsivity

Introduction: Impairments in the multifaceted neuropsychological construct of cognitive impulsivity are a main feature of chronic tobacco smokers. According to the literature, these cognitive impairments are relevant for the initiation and maintenance of the smoking behavior. However, the neuroanatomical correlates of cognitive impulsivity in chronic smokers remain under-investigated.Methods: A sample of 28 chronic smokers (mean age = 28 years) not affected by polysubstance dependence and 24 matched non-smoker controls was recruited. Voxel Based Morphometry (VBM) was employed to assess Gray Matter (GM) volume differences between smokers and non-smokers. The relationships between GM volume and behavioral manifestations of impulsive choices (5 trial adjusting delay discounting task, ADT-5) and risky decision making (Cambridge Gambling Task, CGT) were also investigated.Results: VBM results revealed GM volume reductions in cortical and striatal brain regions of chronic smokers compared to non-smokers. Additionally, smokers showed heightened impulsive choices (p < 0.01, Cohen's f = 0.50) and a riskier decision- making process (p < 0.01, Cohen's f = 0.40) compared to non-smokers. GM volume reductions in the left Anterior Cingulate Cortex (ACC) correlated with impaired impulsive and risky choices, while GM volume reductions in the left Ventrolateral Prefrontal Cortex (VLPFC) and Caudate correlated with heightened impulsive choices. Reduced GM volume in the left VLPFC correlated with younger age at smoking initiation (mean = 16 years).Conclusion: Smokers displayed significant GM volume reductions and related cognitive impulsivity impairments compared to non-smoker individuals. Longitudinal studies would be required to assess whether these impairments underline neurocognitive endophenotypes or if they are a consequence of tobacco exposure on the adolescent brain.

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