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1.
Behav Res Methods ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995519

RESUMO

Interpretation biases in the processing of ambiguous affective information are assumed to play an important role in the onset and maintenance of emotional disorders. Reports of low reliability for experimental measures of cognitive biases have called into question previous findings on the association of these measures with markers of mental health and demonstrated the need to systematically evaluate measurement reliability for measures of cognitive biases. We evaluated reliability and correlations with self-report measures of mental health for interpretation bias scores derived from the Ambiguous Cue Task (ACT), an experimental paradigm for the assessment of approach-avoidance behavior towards ambiguous affective stimuli. For a non-clinical sample, the measurement of an interpretation bias with the ACT showed high internal consistency (rSB = .91 - .96, N = 354) and acceptable 2-week test-retest correlations (rPearson = .61 - .65, n = 109). Correlations between the ACT interpretation bias scores and mental health-related self-report measures of personality and well-being were generally small (r ≤ |.11|) and statistically not significant when correcting for multiple comparisons. These findings suggest that in non-clinical populations, individual differences in the interpretation of ambiguous affective information as assessed with the ACT do not show a clear association with self-report markers of mental health. However, in allowing for a highly reliable measurement of interpretation bias, the ACT provides a valuable tool for studies considering potentially small effect sizes in non-clinical populations by studying bigger samples as well as for work on clinical populations, for which potentially greater effects can be expected.

2.
Attach Hum Dev ; 25(1): 35-49, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-33464174

RESUMO

Physical separation from caregivers activates attachment-related behaviors. However, neural underpinnings of this biological mechanism in humans and their development are poorly understood. We examined via functional MRI brain responses to pictorial representations of separation as a function of attachment-security, attachment-avoidance, and attachment-anxiety measured using the Child-Attachment-Interview, in 30 typically developing children (9-11 years). Attachment-related stimuli elicited enhanced activation in the precuneus, temporoparietal junction area, and medial superior frontal gyrus (described as mentalization network). More negatively rated attachment stimuli yielded increased activity in the inferior frontal gyrus/anterior insula and dorsal anterior cingulate cortex/ACC. Furthermore, ACC responses to attachment-related as compared to control stimuli were positively correlated with attachment-security and negatively correlated with attachment-avoidance. Our findings suggest that processing of separation cues elicits increased mentalization-related processing in children and activation of the salience network with increased negative valence of stimuli. Avoidant vs. securely attached children differentially activate ACC-dependent processes of affective evaluation.


Assuntos
Mapeamento Encefálico , Sinais (Psicologia) , Criança , Humanos , Apego ao Objeto , Encéfalo/fisiologia , Imageamento por Ressonância Magnética
3.
Eur Arch Psychiatry Clin Neurosci ; 272(5): 793-806, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35107603

RESUMO

Youth with attention-deficit/hyperactivity disorder (ADHD) are at increased risk to develop co-morbid depression. Identifying factors that contribute to depression risk may allow early intervention and prevention. Poor emotion regulation, which is common in adolescents, is a candidate risk factor. Impaired cognitive emotion regulation is a fundamental characteristic of depression and depression risk in the general population. However, little is known about cognitive emotion regulation in youth with ADHD and its link to depression and depression risk. Using explicit and implicit measures, this study assessed cognitive emotion regulation in youth with ADHD (N = 40) compared to demographically matched healthy controls (N = 40) and determined the association with depressive symptomatology. As explicit measure, we assessed the use of cognitive emotion regulation strategies via self-report. As implicit measure, performance in an ambiguous cue-conditioning task was assessed as indicator of affective bias in the processing of information. Compared to controls, patients reported more frequent use of maladaptive (i.e., self-blame, catastrophizing, and rumination) and less frequent use of adaptive (i.e., positive reappraisal) emotion regulation strategies. This pattern was associated with the severity of current depressive symptoms in patients. In the implicit measure of cognitive bias, there was no significant difference in response of patients and controls and no association with depression. Our findings point to depression-related alterations in the use of cognitive emotion regulation strategies in youth with ADHD. The study suggests those alterations as a candidate risk factor for ADHD-depression comorbidity that may be used for risk assessment and prevention strategies.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Regulação Emocional , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Cognição , Comorbidade , Depressão/etiologia , Depressão/psicologia , Emoções/fisiologia , Humanos
4.
Neurosci Biobehav Rev ; 162: 105727, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38759742

RESUMO

This review synthesises individual differences in neural processes related to emotion regulation (ER). It comprises individual differences in self-reported and physiological regulation success, self-reported ER-related traits, and demographic variables, to assess their correlation with brain activation during ER tasks. Considering region-of-interest (ROI) and whole-brain analyses, the review incorporated data from 52 functional magnetic resonance imaging studies. Results can be summarized as follows: (1) Self-reported regulation success (assessed by emotional state ratings after regulation) and self-reported ER-related traits (assessed by questionnaires) correlated with brain activity in the lateral prefrontal cortex. (2) Amygdala activation correlated with ER-related traits only in ROI analyses, while it was associated with regulation success in whole-brain analyses. (3) For demographic and physiological measures, there was no systematic overlap in effects reported across studies. In showing that individual differences in regulation success and ER-related traits can be traced back to differences in the neural activity of brain regions associated with emotional reactivity (amygdala) and cognitive control (lateral prefrontal cortex), our findings can inform prospective personalised intervention models.


Assuntos
Encéfalo , Regulação Emocional , Individualidade , Humanos , Regulação Emocional/fisiologia , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tonsila do Cerebelo/fisiologia , Tonsila do Cerebelo/diagnóstico por imagem , Emoções/fisiologia , Mapeamento Encefálico , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem
5.
PLoS One ; 19(2): e0295562, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306328

RESUMO

Positive Appraisal Style Theory of Resilience posits that a person's general style of evaluating stressors plays a central role in mental health and resilience. Specifically, a tendency to appraise stressors positively (positive appraisal style; PAS) is theorized to be protective of mental health and thus a key resilience factor. To this date no measures of PAS exist. Here, we present two scales that measure perceived positive appraisal style, one focusing on cognitive processes that lead to positive appraisals in stressful situations (PASS-process), and the other focusing on the appraisal contents (PASS-content). For PASS-process, the items of the existing questionnaires Brief COPE and CERQ-short were analyzed in exploratory and confirmatory factor analyses (EFA, CFA) in independent samples (N = 1157 and N = 1704). The resulting 10-item questionnaire was internally consistent (α = .78, 95% CI [.86, .87]) and showed good convergent and discriminant validity in comparisons with self-report measures of trait optimism, neuroticism, urgency, and spontaneity. For PASS-content, a newly generated item pool of 29 items across stressor appraisal content dimensions (probability, magnitude, and coping potential) were subjected to EFA and CFA in two independent samples (N = 1174 and N = 1611). The resulting 14-item scale showed good internal consistency (α = .87, 95% CI [.86, .87]), as well as good convergent and discriminant validity within the nomological network. The two scales are a new and reliable way to assess self-perceived positive appraisal style in large-scale studies, which could offer key insights into mechanisms of resilience.


Assuntos
Testes Psicológicos , Resiliência Psicológica , Humanos , Autorrelato , Saúde Mental , Inquéritos e Questionários , Análise Fatorial , Reprodutibilidade dos Testes , Psicometria
6.
Proc Natl Acad Sci U S A ; 107(50): 21767-72, 2010 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-21118983

RESUMO

When we make decisions, the benefits of an option often need to be weighed against accompanying costs. Little is known, however, about the neural systems underlying such cost-benefit computations. Using functional magnetic resonance imaging and choice modeling, we show that decision making based on cost-benefit comparison can be explained as a stochastic accumulation of cost-benefit difference. Model-driven functional MRI shows that ventromedial and left dorsolateral prefrontal cortex compare costs and benefits by computing the difference between neural signatures of anticipated benefits and costs from the ventral striatum and amygdala, respectively. Moreover, changes in blood oxygen level dependent (BOLD) signal in the bilateral middle intraparietal sulcus reflect the accumulation of the difference signal from ventromedial prefrontal cortex. In sum, we show that a neurophysiological mechanism previously established for perceptual decision making, that is, the difference-based accumulation of evidence, is fundamental also in value-based decisions. The brain, thus, weighs costs against benefits by combining neural benefit and cost signals into a single, difference-based neural representation of net value, which is accumulated over time until the individual decides to accept or reject an option.


Assuntos
Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Análise Custo-Benefício , Tomada de Decisões/fisiologia , Animais , Encéfalo/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Oxigênio/sangue , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Adulto Jovem
7.
Emotion ; 23(8): 2331-2343, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37155266

RESUMO

Individual differences in emotion regulation (ER) are assumed to play an important role in resilience and mental health. In a standardized laboratory setting, we investigated how the individual tendency to select specific ER strategies (reappraisal vs. distraction) and the capacity to implement these strategies are related (a) to each other and (b) to trait markers of mental health in a nonclinical sample. For 159 participants, individual regulatory tendency and capacity were assessed with established experimental tasks focusing on ER selection and implementation, respectively. Trait markers of mental health were assessed with questionnaires on ER habits, trait resilience, and well-being. We observed that ER tendency and capacity were positively correlated specifically for the condition in which participants were facing negative stimuli of high intensity. Furthermore, while ER capacity was not consistently associated with trait markers of mental health, a higher tendency to choose reappraisal (as opposed to distraction) was associated with higher trait resilience and better well-being. This study is the first to provide experimental evidence that a person's tendency to select a particular ER strategy is associated with the person's capacity to implement it successfully. Moreover, based on experimental data, we confirm an association between reappraisal tendency and mental health that has previously been suggested by questionnaire studies. This points to regulatory selection as a potential target for interventions fostering resilience and mental health. In the next step, intervention studies should clarify whether the association reflects a causal influence of regulation tendency on resilience. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Regulação Emocional , Humanos , Regulação Emocional/fisiologia , Emoções/fisiologia , Individualidade , Saúde Mental , Inquéritos e Questionários
8.
J Cogn Neurosci ; 24(12): 2385-99, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22905818

RESUMO

The pFC is critical for cognitive flexibility (i.e., our ability to flexibly adjust behavior to changing environmental demands), but also for cognitive stability (i.e., our ability to follow behavioral plans in the face of distraction). Behavioral research suggests that individuals differ in their cognitive flexibility and stability, and neurocomputational theories of working memory relate this variability to the concept of attractor stability in recurrently connected neural networks. We introduce a novel task paradigm to simultaneously assess flexible switching between task rules (cognitive flexibility) and task performance in the presence of irrelevant distractors (cognitive stability) and to furthermore assess the individual "spontaneous switching rate" in response to ambiguous stimuli to quantify the individual dispositional cognitive flexibility in a theoretically motivated way (i.e., as a proxy for attractor stability). Using fMRI in healthy human participants, a common network consisting of parietal and frontal areas was found for task switching and distractor inhibition. More flexible persons showed reduced activation and reduced functional coupling in frontal areas, including the inferior frontal junction, during task switching. Most importantly, the individual spontaneous switching rate antagonistically affected the functional coupling between inferior frontal junction and the superior frontal gyrus during task switching and distractor inhibition, respectively, indicating that individual differences in cognitive flexibility and stability are indeed related to a common prefrontal neural mechanism. We suggest that the concept of attractor stability of prefrontal working memory networks is a meaningful model for individual differences in cognitive stability versus flexibility.


Assuntos
Cognição/fisiologia , Individualidade , Córtex Pré-Frontal/fisiologia , Adulto , Análise de Variância , Sinais (Psicologia) , Feminino , Fixação Ocular , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/fisiologia , Vias Neurais/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem
9.
Cogn Affect Behav Neurosci ; 12(3): 571-88, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22644759

RESUMO

The present study investigates the effects of trait anxiety on the neural efficiency of working memory component functions (manipulation vs. maintenance) in the absence of threat-related stimuli. For the manipulation of affectively neutral verbal information held in working memory, high- and low-anxious individuals (N = 46) did not differ in their behavioral performance, yet trait anxiety was positively related to the neural effort expended on task processing, as measured by BOLD signal changes in fMRI. Higher levels of anxiety were associated with stronger activation in two regions implicated in the goal-directed control of attention--that is, right dorsolateral prefrontal cortex (DLPFC) and left inferior frontal sulcus--and with stronger deactivation in a region assigned to the brain's default-mode network--that is, rostral-ventral anterior cingulate cortex. Furthermore, anxiety was associated with a stronger functional coupling of right DLPFC with ventrolateral prefrontal cortex. We interpret our findings as reflecting reduced processing efficiency in high-anxious individuals and point out the need to consider measures of functional integration in addition to measures of regional activation strength when investigating individual differences in neural efficiency. With respect to the functions of working memory, we conclude that anxiety specifically impairs the processing efficiency of (control-demanding) manipulation processes (as opposed to mere maintenance). Notably, this study contributes to an accumulating body of evidence showing that anxiety also affects cognitive processing in the absence of threat-related stimuli.


Assuntos
Ansiedade/psicologia , Encéfalo/fisiopatologia , Memória de Curto Prazo/fisiologia , Rede Nervosa/fisiopatologia , Personalidade/fisiologia , Adulto , Ansiedade/fisiopatologia , Atenção/fisiologia , Mapeamento Encefálico , Cognição/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia
10.
Transl Psychiatry ; 12(1): 396, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130942

RESUMO

The COVID-19 pandemic is a global stressor with inter-individually differing influences on mental health trajectories. Polygenic Risk Scores (PRSs) for psychiatric phenotypes are associated with individual mental health predispositions. Elevated hair cortisol concentrations (HCC) and high PRSs are related to negative mental health outcomes. We analyzed whether PRSs and HCC are related to different mental health trajectories during the first COVID lockdown in Germany. Among 523 participants selected from the longitudinal resilience assessment study (LORA), we previously reported three subgroups (acute dysfunction, delayed dysfunction, resilient) based on weekly mental health (GHQ-28) assessment during COVID lockdown. DNA from blood was collected at the baseline of the original LORA study (n = 364) and used to calculate the PRSs of 12 different psychopathological phenotypes. An explorative bifactor model with Schmid-Leiman transformation was calculated to extract a general genetic factor for psychiatric disorders. Hair samples were collected quarterly prior to the pandemic for determining HCC (n = 192). Bivariate logistic regressions were performed to test the associations of HCC and the PRS factors with the reported trajectories. The bifactor model revealed 1 general factor and 4 sub-factors. Results indicate a significant association between increased values on the general risk factor and the allocation to the acute dysfunction class. The same was found for elevated HCC and the exploratorily tested sub-factor "childhood-onset neurodevelopmental disorders". Genetic risk and long-term cortisol secretion as a potential indicator of stress, indicated by PRSs and HCC, respectively, predicted different mental health trajectories. Results indicate a potential for future studies on risk prediction.


Assuntos
COVID-19 , Hidrocortisona , Controle de Doenças Transmissíveis , Cabelo , Humanos , Saúde Mental , Pandemias , Fatores de Risco
11.
J Neurosci ; 30(42): 14205-12, 2010 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-20962241

RESUMO

Recent studies suggest an association of dopamine D2 receptor (DRD2) availability with flexibility in reward-based learning. We extend these results by demonstrating an association of genetically based differences in DRD2 density with the ability to intentionally switch between nonrewarded tasks: noncarriers of the A1 allele of the DRD2/ANKK1-TaqIa polymorphism, associated with higher DRD2 density, show increased task-switching costs, increased prefrontal switching activity in the inferior frontal junction area, and increased functional connectivity in dorsal frontostriatal circuits, relative to A1 allele carriers. A DRD2 haplotype analysis in the same sample confirmed these results, indicating an association between high D2 density and increased task-switching effort. Our results provide evidence that converges with that from association studies relating increased D2 density to deficits in cognitive flexibility in schizophrenia. We suggest that individual differences in striatal D2 signaling in healthy humans modulate goal-directed gating to prefrontal cortex, thus leading to individual differences in switching intentionally to newly relevant behaviors.


Assuntos
Corpo Estriado/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/fisiologia , Cognição/fisiologia , DNA/genética , Feminino , Haplótipos , Humanos , Individualidade , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Plasticidade Neuronal/genética , Plasticidade Neuronal/fisiologia , Polimorfismo Genético/genética , Proteínas Serina-Treonina Quinases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
12.
J Cogn Neurosci ; 23(10): 3132-45, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21391763

RESUMO

An impairment of attentional control in the face of threat-related distracters is well established for high-anxious individuals. Beyond that, it has been hypothesized that high trait anxiety more generally impairs the neural efficiency of cognitive processes requiring attentional control-even in the absence of threat-related stimuli. Here, we use fMRI to show that trait anxiety indeed modulates brain activation and functional connectivities between task-relevant brain regions in an affectively neutral Stroop task. In high-anxious individuals, dorsolateral pFC showed stronger task-related activation and reduced coupling with posterior lateral frontal regions, dorsal ACC, and a word-sensitive area in the left fusiform gyrus. These results support the assumption that a general (i.e., not threat-specific) impairment of attentional control leads to reduced neural processing efficiency in anxious individuals. The increased dorsolateral pFC activation is interpreted as an attempt to compensate for suboptimal connectivity within the cortical network subserving task performance.


Assuntos
Ansiedade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Mapeamento Encefálico , Lobo Frontal/fisiopatologia , Inibição Psicológica , Adulto , Ansiedade/patologia , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Feminino , Lobo Frontal/irrigação sanguínea , Humanos , Processamento de Imagem Assistida por Computador , Modelos Logísticos , Imageamento por Ressonância Magnética/métodos , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Escalas de Graduação Psiquiátrica , Psicofísica , Tempo de Reação , Estatística como Assunto , Adulto Jovem
13.
J Cogn Neurosci ; 23(11): 3529-39, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21568635

RESUMO

Task representations consist of different aspects such as the representations of the relevant stimuli, the abstract rules to be applied, and the actions to be performed. To be flexible in our daily lives, we frequently need to switch between some or all aspects of a task. In the present study, we examined whether switching between abstract task rules and switching between response hands is associated with overlapping regions in the posterior lateral frontal cortex and whether switching between these two aspects of a task representation is neurally implemented by distinct functional brain networks. Subjects performed a cue-based task-switching paradigm where the location of the task cue additionally specified the response hand to be used. Overlapping activity for switching between abstract rules versus response hands was present in the inferior frontal junction area of the posterolateral frontal cortex. This region, however, showed very distinct patterns of functional connectivity depending on the content of the switch: Increased functional connectivity with anterior prefrontal, superior frontal, and hippocampal regions was present for abstract rule switching, whereas response hand switching led to increased coupling with motor regions surrounding the central sulcus. These results reveal that a rather general involvement of the posterior lateral frontal cortex in different switching contexts can be further characterized by highly specific functional interactions with other task-relevant regions, depending on the content of the switch.


Assuntos
Atenção/fisiologia , Mapeamento Encefálico , Lobo Frontal/fisiologia , Vias Neurais/fisiologia , Desempenho Psicomotor/fisiologia , Análise de Variância , Feminino , Lobo Frontal/irrigação sanguínea , Mãos , Hipocampo/irrigação sanguínea , Hipocampo/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/irrigação sanguínea , Oxigênio/sangue , Estimulação Luminosa , Adulto Jovem
14.
Front Psychol ; 12: 710493, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539510

RESUMO

Resilience has been defined as the maintenance or quick recovery of mental health during and after times of adversity. How to operationalize resilience and to determine the factors and processes that lead to good long-term mental health outcomes in stressor-exposed individuals is a matter of ongoing debate and of critical importance for the advancement of the field. One of the biggest challenges for implementing an outcome-based definition of resilience in longitudinal observational study designs lies in the fact that real-life adversity is usually unpredictable and that its substantial qualitative as well as temporal variability between subjects often precludes defining circumscribed time windows of inter-individually comparable stressor exposure relative to which the maintenance or recovery of mental health can be determined. To address this pertinent issue, we propose to frequently and regularly monitor stressor exposure (E) and mental health problems (P) throughout a study's observation period [Frequent Stressor and Mental Health Monitoring (FRESHMO)-paradigm]. On this basis, a subject's deviation at any single monitoring time point from the study sample's normative E-P relationship (the regression residual) can be used to calculate that subject's current mental health reactivity to stressor exposure ("stressor reactivity," SR). The SR score takes into account the individual extent of experienced adversity and is comparable between and within subjects. Individual SR time courses across monitoring time points reflect intra-individual temporal variability in SR, where periods of under-reactivity (negative SR score) are associated with accumulation of fewer mental health problems than is normal for the sample. If FRESHMO is accompanied by regular measurement of potential resilience factors, temporal changes in resilience factors can be used to predict SR time courses. An increase in a resilience factor measurement explaining a lagged decrease in SR can then be considered to index a process of adaptation to stressor exposure that promotes a resilient outcome (an allostatic resilience process). This design principle allows resilience research to move beyond merely determining baseline predictors of resilience outcomes, which cannot inform about how individuals successfully adjust and adapt when confronted with adversity. Hence, FRESHMO plus regular resilience factor monitoring incorporates a dynamic-systems perspective into resilience research.

15.
Psychiatry Res ; 179(1): 86-90, 2010 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-20478625

RESUMO

Mounting evidence shows that the brain derived neurotrophic factor (BDNF) plays a crucial role in depression and anxiety. The discovery of a functional variant of the BDNF gene--the BDNF Val66Met polymorphism--led to new insights into the molecular genetic mechanisms underlying these emotional disorders. Although there is evidence from animal research that the homozygous BDNF 66Met variant is associated with anxiety-like behaviour, findings from personality research using self-report-measures as indicators of trait anxiety are heterogenous. Recent seminal findings from a study using a knock-in mouse design suggest that this Met66Met group is of particular interest for the investigation of the molecular genetic mechanisms of anxiety and anxiety-related personality traits in humans. In a sample of 610 Caucasian participants, subjects homozygous for the 66Met allele scored significantly higher than Val66 allele carriers on anxiety-related facets of the construct 'harm avoidance' (i.e., 'anticipatory worry' and 'fear of uncertainty') of the Temperament and Character Inventory. This finding adds to a small plurality of studies that associates the 66Met allele, rather than the Val66 allele, with higher anxiety scores. Importantly, the present results furthermore suggest that it is the occurrence of not one but two 66Met alleles that is associated with high trait anxiety.


Assuntos
Ansiedade/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Metionina/genética , Polimorfismo de Nucleotídeo Único/genética , Valina/genética , Adolescente , Adulto , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Análise Multivariada , Comportamento Autodestrutivo/genética , Fatores Sexuais , Adulto Jovem
16.
Brain Struct Funct ; 225(7): 2111-2129, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32696074

RESUMO

A positive association between brain size and intelligence is firmly established, but whether region-specific anatomical differences contribute to general intelligence remains an open question. Results from voxel-based morphometry (VBM) - one of the most widely used morphometric methods - have remained inconclusive so far. Here, we applied cross-validated machine learning-based predictive modeling to test whether out-of-sample prediction of individual intelligence scores is possible on the basis of voxel-wise gray matter volume. Features were derived from structural magnetic resonance imaging data (N = 308) using (a) a purely data-driven method (principal component analysis) and (b) a domain knowledge-based approach (atlas parcellation). When using relative gray matter (corrected for total brain size), only the atlas-based approach provided significant prediction, while absolute gray matter (uncorrected) allowed for above-chance prediction with both approaches. Importantly, in all significant predictions, the absolute error was relatively high, i.e., greater than ten IQ points, and in the atlas-based models, the predicted IQ scores varied closely around the sample mean. This renders the practical value even of statistically significant prediction results questionable. Analyses based on the gray matter of functional brain networks yielded significant predictions for the fronto-parietal network and the cerebellum. However, the mean absolute errors were not reduced in contrast to the global models, suggesting that general intelligence may be related more to global than region-specific differences in gray matter volume. More generally, our study highlights the importance of predictive statistical analysis approaches for clarifying the neurobiological bases of intelligence and provides important suggestions for future research using predictive modeling.


Assuntos
Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Inteligência/fisiologia , Adolescente , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Testes de Inteligência , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/fisiologia , Adulto Jovem
17.
Eur J Neurosci ; 29(5): 1056-63, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19291230

RESUMO

Dopamine modulates complex cognitive functions like working memory and cognitive control. It is widely accepted that an optimal level of prefrontal dopamine supports working memory performance. In the present study we used a molecular genetic approach to test whether the optimal activity of the dopamine system for different component processes of working memory is additionally related to the availability of dopamine D2 receptors. We sought evidence for this assumption by investigating the interaction effect (epistasis) of variations in two dopaminergic candidate genes: the catechol-O-methyltransferase (COMT) Val(158)Met polymorphism, which has been shown to influence prefrontal dopamine concentration, and the DRD2/ANKK1-Taq-Ia polymorphism, which has been related to the density of D2 receptors. Our results show that COMT effects on working memory performance are modulated by the DRD2/ANKK1-TAQ-Ia polymorphism and the specific working memory component process under investigation. Val-participants--supposedly characterized by increased prefrontal dopamine concentrations--outperformed Val+ participants in the manipulation of working memory contents, but only when D2 receptor density could be considered to be high. No such effect was present for passive maintenance of working memory contents or for maintenance in the face of distracting information. This beneficial effect of a balance between prefrontal dopamine availability and D2 receptor density reveals the importance of considering epistasis effects and different working memory subprocesses in genetic association studies.


Assuntos
Catecol O-Metiltransferase/genética , Dopamina/metabolismo , Memória de Curto Prazo/fisiologia , Polimorfismo Genético/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Dopamina D2/genética , Adulto , Comportamento de Escolha/fisiologia , Feminino , Genótipo , Humanos , Masculino , Matemática , Processos Mentais/fisiologia , Metionina/genética , Testes Neuropsicológicos , Valina/genética , Adulto Jovem
18.
Neurosci Lett ; 442(1): 30-3, 2008 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-18602452

RESUMO

Although the brain derived neurotrophic factor (BDNF) has been mainly investigated in the context of depression and anxiety disorders, several studies also suggest an association between BDNF and smoking. BDNF represents a protein which crucially influences several processes in the cell ranging from growth to apoptosis. A functional variant of the BDNF gene - the BDNF Val66Met polymorphism - is one of the main targets in BDNF research because of its influence on BDNF secretion. Recently an association between the 66Met allele and smoking has been reported in a sample of 320 Caucasians. The aim of the present study was to replicate this association in a sample nearly twice as large consisting of N=614 German Caucasian participants. A link between smoking and the BDNF Val66Met polymorphism could not be found in our data.


Assuntos
Comportamento Aditivo/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Fumar/genética , Adulto , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
19.
Sci Rep ; 7(1): 16088, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29167455

RESUMO

General intelligence is a psychological construct that captures in a single metric the overall level of behavioural and cognitive performance in an individual. While previous research has attempted to localise intelligence in circumscribed brain regions, more recent work focuses on functional interactions between regions. However, even though brain networks are characterised by substantial modularity, it is unclear whether and how the brain's modular organisation is associated with general intelligence. Modelling subject-specific brain network graphs from functional MRI resting-state data (N = 309), we found that intelligence was not associated with global modularity features (e.g., number or size of modules) or the whole-brain proportions of different node types (e.g., connector hubs or provincial hubs). In contrast, we observed characteristic associations between intelligence and node-specific measures of within- and between-module connectivity, particularly in frontal and parietal brain regions that have previously been linked to intelligence. We propose that the connectivity profile of these regions may shape intelligence-relevant aspects of information processing. Our data demonstrate that not only region-specific differences in brain structure and function, but also the network-topological embedding of fronto-parietal as well as other cortical and subcortical brain regions is related to individual differences in higher cognitive abilities, i.e., intelligence.


Assuntos
Encéfalo/fisiologia , Inteligência/fisiologia , Rede Nervosa/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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