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1.
J Anxiety Disord ; 103: 102848, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38431988

RESUMO

Climate change is a global crisis impacting individuals' mental health. Climate anxiety is an emerging area of interest within popular culture and the scientific community. Yet, little is known about the mechanisms underlying climate anxiety. We provide evidence that climate anxiety is related to gray matter volume in the midcingulate cortex as well as its level of functional connectivity with the insula cortex. These neuroanatomical and neurofunctional features of climate anxiety are involved in identifying and anticipating potential threats within the environment and preparing an appropriate action response to such threats. These neural correlates align with those observed in anxiety disorders. Yet, climate anxiety itself as well as the neural correlates of climate anxiety were related to pro-environmental behavior. This may suggest that the midcingulate and insula are part of a network linked to an adaptive aspect of climate anxiety in motivating behavioral engagement.


Assuntos
Mudança Climática , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Transtornos de Ansiedade/psicologia , Ansiedade
2.
Cureus ; 15(7): e41474, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37546107

RESUMO

Hyponatremia refers to an abnormally low serum sodium level, and it is the most common electrolyte disorder encountered in the clinical setting. Despite its prevalence, hyponatremia can be challenging to clinically identify in some cases due to non-specific symptom presentation. In this case report, we illustrate the rare clinical course of a nearly asymptomatic patient with severe hyponatremia and discuss potential explanations for this uncommon presentation.

3.
mBio ; 14(4): e0106423, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37477489

RESUMO

Trypanosoma cruzi is the etiologic agent of Chagas disease, a leading cause of disability and premature death in the Americas. This parasite spends its life between a triatomine insect and a mammalian host, transitioning between developmental stages in response to microenvironmental changes. Among the second messengers driving differentiation in T. cruzi, cAMP has been shown to mediate metacyclogenesis and response to osmotic stress, but this signaling pathway remains largely unexplored in this parasite. Adenylate cyclases (ACs) catalyze the conversion of ATP to cAMP. They comprise a multigene family encoding putative receptor-type ACs in T. cruzi. Using protein sequence alignment, we classified them into five groups and chose a representative member from each group to study their localization (TcAC1-TcAC5). We expressed an HA-tagged version of each protein in T. cruzi and performed immunofluorescence analysis. A peculiar dual localization of TcAC1 and TcAC2 was observed in the flagellar distal domain and in the contractile vacuole complex (CVC), and their enzymatic activity was confirmed by gene complementation in yeast. Furthermore, TcAC1 overexpressing parasites showed an increased metacyclogenesis, a defect in host cell invasion, and a reduced intracellular replication, highlighting the importance of this protein throughout T. cruzi life cycle. These mutants were more tolerant to hypoosmotic stress and showed a higher adhesion capacity during in vitro metacyclogenesis, whereas the wild-type phenotype was restored after disrupting TcAC1 localization. Finally, TcAC1 was found to interact with cAMP response protein 3 (TcCARP3), co-localizing with this protein in the flagellar tip and CVC. IMPORTANCE We identified three components of the cAMP signaling pathway (TcAC1, TcAC2, and TcCARP3) with dual localization in Trypanosoma cruzi: the flagellar distal domain and the CVC, structures involved in cell adhesion and osmoregulation, respectively. We found evidence on the role of TcAC1 in both cellular processes, as well as in metacyclogenesis. Our data suggest that TcACs act as signal sensors and transducers through cAMP synthesis in membrane microdomains. We propose a model in which TcACs sense the harsh conditions in the triatomine hindgut (nutrient deprivation, acidic pH, osmotic stress, ionic composition, hydrophobic interactions) and become active. Synthesis of cAMP then triggers cell adhesion prior completion of metacyclogenesis, while mediating a response to osmotic stress in the parasite. These results shed light into the mechanisms driving cAMP-mediated cell differentiation in T. cruzi, while raising new questions on the activation of TcACs and the role of downstream components of this pathway.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Animais , Trypanosoma cruzi/metabolismo , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Doença de Chagas/parasitologia , Sequência de Aminoácidos , Transdução de Sinais , Mamíferos/metabolismo
4.
PLoS One ; 18(5): e0285839, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37195990

RESUMO

Fearful facial expressions are nonverbal and biologically salient signals of potential threat that automatically hold, capture, and direct observers' attention. They are characterized by enlarged eye whites and dilated pupils, and fearful eyes alone are sufficient to capture attention. The morphological properties of the eye region, such as sclera exposure, are thought to play an important role in nonverbal communication. Specifically, increased sclera exposure associated with fearful expressions has been shown to moderate how observers' shift their attention toward the direction of another's gaze. Yet, the extent to which variability in sclera exposure possibly impacts the capture and hold of attention by fearful faces is untested. To address this, a sample of 249 adults completed a dot-probe task of selective attention with fearful and neutral faces. The results suggested that (1) fearful faces were prioritized over neutral faces (i.e., they captured and held attention), (2) greater sclera exposure at target locations facilitated reaction times, and (3) attention was held by greater sclera exposure of fearful faces at task irrelevant locations resulting in delayed disengagement. Collectively, the results indicate that fearful facial expressions and sclera exposure modulate spatial attention through independent and interactive mechanisms. Sclera exposure appears to be an important facilitator of nonverbal communication and perhaps represents an understudied variable in social cognition more broadly.


Assuntos
Medo , Esclera , Atenção , Tempo de Reação , Expressão Facial
5.
Int J Psychophysiol ; 184: 76-83, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36581044

RESUMO

Enhanced error monitoring has been associated with higher levels of anxiety. This has been consistently demonstrated in its most reliable electrophysiological index, the error-related negativity (ERN), such that increased ERN is related with elevated anxiety symptomology. However, it is still unclear whether the structural properties of the brain are associated with individual differences in ERN amplitude. Moreover, the relationship between ERN and anxiety has recently been suggested to be moderated by sex, but the degree to which sex moderates the association between brain structure and ERN amplitude is unknown. The present study investigated the association between gray matter volume (GMV) and ERN amplitude in individuals with high trait anxiety (N = 98) as well as the role of sex in moderating this association. The ERN was elicited from a flanker task, whereas structural MRI images were obtained from whole brain structural T1-weighted MRI scans. The results of voxel-based morphometry analyses showed that the relationship between ERN difference scores and GMV was moderated by sex in the dorsal anterior cingulate cortex (dACC). This sex difference was derived from a negative correlation between ERN difference scores and dACC GMV in females and a positive correlation in males. Our findings are in accordance with the critical role of the dACC serving as a neural substrate of error monitoring. It also provides further evidence for sex-specific associations with brain structures related to error monitoring.


Assuntos
Eletroencefalografia , Substância Cinzenta , Humanos , Masculino , Feminino , Substância Cinzenta/diagnóstico por imagem , Transtornos de Ansiedade , Córtex Cerebral/diagnóstico por imagem , Ansiedade/diagnóstico por imagem , Potenciais Evocados/fisiologia
6.
Biol Psychol ; 172: 108353, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35569575

RESUMO

Attention bias modification (ABM) was developed to alleviate anxious symptoms by way of a reduction in anxiety-linked attentional bias to threat. Central to the rational of ABM is a learning-related reconfiguration of attentional biases. Yet, the neuroplastic changes in brain structure that underlie this learning are unresolved. The amygdala, anterior cingulate cortex, and lateral prefrontal cortex are part of a system linked to attentional bias to threat and its modification with ABM. We assessed the extent to which ABM modulates gray matter volume and resting-state functional connectivity. Sixty-one individuals selected for attentional bias to threat and heightened trait anxiety completed a 6-week multi-session ABM protocol with 7200 total training trials. Participants were assigned to either an ABM (n = 30) or a control (n = 31) condition. We found that participants' levels of attentional bias and anxiety did not differ following ABM and control training interventions. However, the ABM group displayed greater levels of anterior cingulate cortex gray matter volume as well as greater superior frontal gyrus resting-state functional connectivity with the anterior cingulate cortex and insula. Changes in anterior cingulate cortex gray matter volume were linked to reduced anxious symptoms in the ABM, but not control, group. These findings suggest that ABM distinctively impacts structural and functional neural mechanisms associated with emotion reactivity and cognitive control processes.


Assuntos
Viés de Atenção , Ansiedade/diagnóstico por imagem , Ansiedade/psicologia , Transtornos de Ansiedade/psicologia , Substância Cinzenta/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Humanos
7.
Cogn Affect Behav Neurosci ; 22(3): 600-609, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34755317

RESUMO

In a sample of highly anxious individuals, the relationship between gray matter volume brain morphology and attentional bias to threat was assessed. Participants performed a dot-probe task of attentional bias to threat and gray matter volume was acquired from whole brain structural T1-weighted magnetic resonance imaging scans. The results replicate previous findings in unselected samples that elevated attentional bias to threat is linked to greater gray matter volume in the middle frontal gyrus and superior frontal gyrus. In addition, we provide novel evidence that elevated attentional bias to threat is associated with greater gray matter volume in the inferior frontal gyrus, insula, cerebellum, and other distributed regions. Lastly, exploratory analyses provide initial evidence that distinct subregions of the right posterior parietal cortex may contribute to attentional bias in a sex-specific manner. Our results illuminate how differences in gray matter volume morphology relate to attentional bias to threat in anxious individuals. This knowledge could inform neurocognitive models of anxiety-related attentional bias to threat.


Assuntos
Viés de Atenção , Substância Cinzenta , Ansiedade/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino
8.
Front Psychol ; 13: 1021858, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36710831

RESUMO

Climate change is one of the most pressing issues of the 21st century, which is perhaps why information about climate change has been found to capture observers' attention. One of the most common ways of assessing individual differences in attentional processing of climate change information is through the use of reaction time difference scores. However, reaction time-based difference scores have come under scrutiny for their low reliability. Given that a primary goal of the field is to link individual differences in attention processing to participant variables (e.g., environmental attitudes), we assessed the reliability of reaction time-based measures of attention processing of climate change information utilizing an existing dataset with three variations of the dot-probe task. Across all three samples, difference score-based measures of attentional bias were generally uncorrelated across task blocks (r = -0.25 to 0.31). We also assessed the reliability of newer attention bias variability measures that are thought to capture dynamic shifts in attention toward and away from salient information. Although these measures were initially found to be correlated across task blocks (r = 0.17-0.67), they also tended to be highly correlated with general reaction time variability (r = 0.49-0.83). When controlling for general reaction time variability, the correlations across task blocks for attention bias variability were much weaker and generally nonsignificant (r = -0.25 to 0.33). Furthermore, these measures were unrelated to pro-environmental disposition indicating poor predictive validity. In short, reaction time-based measures of attentional processing (including difference score and variability-based approaches) have unacceptably low levels of reliability and are therefore unsuitable for capturing individual differences in attentional bias to climate change information.

9.
J Affect Disord Rep ; 102022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36684713

RESUMO

Background: Attention bias variability is thought to measure fluctuations in attention towards and away from threat-related information and is elevated in affective disorders. However, recent evidence suggests that attention bias variability may quantify general reaction time variability rather than attention bias behavior per se. Methods: The current study calculated "attention bias variability" from two conceptually unrelated cognitive tasks: the dot-probe task (measuring attentional bias) and the arrow flanker task (measuring cognitive control). Results: Attention bias variability measures were correlated across these unrelated tasks. Yet, when general reaction time variability was controlled, attention bias variability across tasks was no longer correlated. In addition, the reliability of attention bias variability measures decreased when controlling for general reaction time variability. Finally, although attention bias variability calculated from the dot-probe task initially correlated with anxious symptoms, this association was no longer significant when controlling for general reaction time variability. Limitations: Our sample was comprised of high trait anxious individuals. Replication in clinical samples is warranted. Conclusions: These findings collectively provide strong empirical evidence that attention bias variability is not a valid measure of attention-related behavior, but reflective of general reaction time variability more broadly.

10.
Proc Natl Acad Sci U S A ; 118(50)2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34873047

RESUMO

The Halibee member of the Upper Dawaitoli Formation of Ethiopia's Middle Awash study area features a wealth of Middle and Later Stone Age (MSA and LSA) paleoanthropological resources in a succession of Pleistocene sediments. We introduce these artifacts and fossils, and determine their chronostratigraphic placement via a combination of established radioisotopic methods and a recently developed dating method applied to ostrich eggshell (OES). We apply the recently developed 230Th/U burial dating of OES to bridge the temporal gap between radiocarbon (14C) and 40Ar/39Ar ages for the MSA and provide 14C ages to constrain the younger LSA archaeology and fauna to ∼24 to 21.4 ka. Paired 14C and 230Th/U burial ages of OES agree at ∼31 ka for an older LSA locality, validating the newer method, and in turn supporting its application to stratigraphically underlying MSA occurrences previously constrained only by a maximum 40Ar/39Ar age. Associated fauna, flora, and Homo sapiens fossils are thereby now fixed between 106 ± 20 ka and 96.4 ± 1.6 ka (all errors 2σ). Additional 40Ar/39 results on an underlying tuff refine its age to 158.1 ± 11.0 ka, providing a more precise minimum age for MSA lithic artifacts, fauna, and H. sapiens fossils recovered ∼9 m below it. These results demonstrate how chronological control can be obtained in tectonically active and stratigraphically complex settings to precisely calibrate crucial evidence of technological, environmental, and evolutionary changes during the African Middle and Late Pleistocene.

11.
Front Hum Neurosci ; 15: 627589, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093149

RESUMO

Anxiety disorders are more predominant in women than men, however there is a lack of understanding as to what neurocognitive mechanisms drive this sex difference. Recent investigation has found a potential moderating role of sex in the relationship between anxiety and the error related negativity (ERN)-a component of error-monitoring that is prevalent in high anxiety individuals-such that females display a positive relationship between anxiety/worry and ERN amplitude. We strove to further explore the influence of sex on the relationship between trait anxiety and performance monitoring, specifically with ERN, as well as extend this work to include another hallmark of anxiety, attentional bias to threat. To meet this end, participants performed the flanker and dot-probe tasks, respectively. We did not find a significant difference in the relationship between attention bias scores and anxiety for female vs. males participants. Furthermore, ΔERN amplitudes were greater in males compared to females, and males had more positive CRN amplitudes than females. There were no significant associations between ERN or ΔERN with anxiety in both male and female participants. However, there was a significant relationship between CRN amplitudes and trait anxiety in male but not female participants. Given these results, the effect of sex on the relationship between components of performance monitoring-namely the CRN and ERN-and anxiety may be more nuanced than the current understanding. Our study was limited to detecting medium to large sized moderation effects. Our findings may be important for future meta-analysis on sex differences in anxiety.

12.
Int J Psychophysiol ; 165: 84-91, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33892017

RESUMO

Attending toward fearful faces and other threatening stimuli increase the chance of survival. The dot-probe task is a commonly used measure of spatial attention. Event-related potentials (ERPs) have been found to be a reliable measure of attentional bias. The dot-probe literature suggests that posterior contralateral N170 amplitudes are more enhanced by fearful faces compared to ipsilateral amplitudes. However, ERP methods remove non-phase locked frequencies, which provides additional information about neural activity. Specifically, theta oscillations (5-7 Hz) have been linked to attentional processing. The purpose of this study was to examine the relationship between posterior contralateral theta oscillations and N170 amplitudes in the dot-probe task. A modified dot-probe task was used with fear and neutral facial expressions and EEG data was recorded from 33 electrodes. The ERP and time-frequency data were extracted from the P7 and P8 electrodes (left and right occipitotemporal regions). This study found enhanced N170 amplitude and theta oscillations in the electrodes posterior contralateral to the fearful face. Contralateral N170 amplitudes and theta oscillations were related such that greater N170 amplitudes were associated with greater theta oscillations. The results indicated that increased contralateral N170 and theta oscillations are related to each other and underlie attentional bias to fearful faces.


Assuntos
Viés de Atenção , Eletroencefalografia , Potenciais Evocados , Expressão Facial , Medo , Humanos , Couro Cabeludo
13.
J Community Psychol ; 49(7): 2441-2453, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33899228

RESUMO

People experiencing homelessness are at risk for coronavirus disease 2019 (COVID-19) and may experience barriers to hand hygiene, a primary recommendation for COVID-19 prevention. We conducted in-depth interviews with 51 people experiencing sheltered and unsheltered homelessness in Atlanta, Georgia during May 2020 to August 2020 to (1) describe challenges and opportunities related to hand hygiene and (2) assess hand hygiene communication preferences. The primary hand hygiene barrier reported was limited access to facilities and supplies, which has disproportionately impacted people experiencing unsheltered homelessness. This lack of access has reportedly been exacerbated during COVID-19 by the closure of public facilities and businesses. Increased access to housing and employment were identified as long-term solutions to improving hand hygiene. Overall, participants expressed a preference for access to facilities and supplies over hand hygiene communication materials.


Assuntos
COVID-19/epidemiologia , COVID-19/prevenção & controle , Higiene das Mãos , Pessoas Mal Alojadas , Adulto , Idoso , Feminino , Georgia/epidemiologia , Comunicação em Saúde , Humanos , Masculino , Pessoa de Meia-Idade
14.
Psychophysiology ; 58(6): e13801, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33682161

RESUMO

Attention bias modification (ABM) was initially developed with the goal of reducing attentional bias to threat-and subsequently anxious symptoms-in individuals with heightened anxiety. Although controversial, ABM appears to be generally effective in achieving this goal. Yet, the primary outcome measure of ABM (i.e., the reaction time-based differences score) has poor reliability and temporal resolution, which limits the inferences that can be drawn. In contrast, event-related potentials (ERPs) have superior reliability as well as temporal resolution and may therefore be better outcome measures of ABM. In this review, I systematically assess the research using ERPs as outcome measures in ABM protocols. I focus on the extent to which the ERPs modified by ABM represent earlier or later stages of information processing. In addition, I explore the extent to which ABM produces near and/or far transfer of learning effects on ERP measures. The reviewed literature suggests that ERPs are promising outcome measures of ABM. ABM modulates the effects of affective stimuli on posterior visually evoked ERPs (i.e., P1) as well as ERPs at anterior electrodes (i.e., P2, N2, and ERN). Based on the state of the field, several directions for future research are identified.


Assuntos
Viés de Atenção/fisiologia , Potenciais Evocados/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Ansiedade/psicologia , Humanos , Tempo de Reação , Reprodutibilidade dos Testes
15.
Psychophysiology ; 58(5): e13794, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33624288

RESUMO

The error-related negativity (ERN) is a response-locked event-related potential, occurring approximately 50 ms following an erroneous response at frontocentral electrode sites. Source localization and functional magnetic resonance imaging (fMRI) research indicate that the ERN is likely generated by activity in the dorsal anterior cingulate cortex (dACC). The dACC is thought to be a part of a broader network of brain regions that collectively comprise an error monitoring network. However, little is known about how intrinsic connectivity within the dACC-based error monitoring network contributes to variability in ERN amplitude. The purpose of this study was to assess the relationship between dACC functional connectivity and ERN amplitude. In a sample of highly trait anxious individuals, the ERN was elicited in a flanker task and functional connectivity was assessed in a 10-min resting-state fMRI scan. Results suggest that the strength of dACC seeded functional connectivity with the supplementary motor area is correlated with the ΔERN (i.e., incorrect-correct responses) amplitude such that greater ΔERN amplitude was accompanied by greater functional coupling between these regions. In sum, ERN amplitude appears to be related to the strength of functional connectivity between error monitoring and motor control regions of the brain.


Assuntos
Giro do Cíngulo/diagnóstico por imagem , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Eletroencefalografia , Feminino , Neuroimagem Funcional , Giro do Cíngulo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais , Adulto Jovem
16.
J Manag Care Spec Pharm ; 27(1): 95-104, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33377442

RESUMO

Results of randomized controlled trials (RCTs) provide valuable comparisons of 2 or more interventions to inform health care decision making; however, many more comparisons are required than available time and resources to conduct them. Moreover, RCTs have limited generalizability. Comparative effectiveness research (CER) using real-world evidence (RWE) can increase generalizability and is important for decision making, but use of nonrandomized designs makes their evaluation challenging. Several tools are available to assist. In this study, we comparatively characterize 5 tools used to evaluate RWE studies in the context of making health care adoption decision making: (1) Good Research for Comparative Effectiveness (GRACE) Checklist, (2) IMI GetReal RWE Navigator (Navigator), (3) Center for Medical Technology Policy (CMTP) RWE Decoder, (4) CER Collaborative tool, and (5) Real World Evidence Assessments and Needs Guidance (REAdi) tool. We describe each and then compare their features along 8 domains: (1) objective/user/context, (2) development/scope, (3) platform/presentation, (4) user design, (5) study-level internal/external validity of evidence, (6) summarizing body of evidence, (7) assisting in decision making, and (8) sharing results/making improvements. Our summary suggests that the GRACE Checklist aids stakeholders in evaluation of the quality and applicability of individual CER studies. Navigator is a collection of educational resources to guide demonstration of effectiveness, a guidance tool to support development of medicines, and a directory of authoritative resources for RWE. The CMTP RWE Decoder aids in the assessment of relevance and rigor of RWE. The CER Collaborative tool aids in the assessment of credibility and relevance. The REAdi tool aids in refinement of the research question, study retrieval, quality assessment, grading the body of evidence, and prompts with questions to facilitate coverage decisions. All tools specify a framework, were designed with stakeholder input, assess internal validity, are available online, and are easy to use. They vary in their complexity and comprehensiveness. The RWE Decoder, CER Collaborative tool, and REAdi tool synthesize evidence and were specifically designed to aid formulary decision making. This study adds clarity on what the tools provide so that the user can determine which best fits a given purpose. DISCLOSURES: This work was supported by the Health Tech Fund, which was provided to the University of Washington School of Pharmacy by its Corporate Advisory Board. This consortium of pharmaceutical and biotech companies supports the research program of the University of Washington School of Pharmacy across the competitive space. The sponsors seeded the idea for the project and contributed to study design and improvement. The authors had full control of all content development, manuscript drafting, and submission for publication. The REAdi tool was developed by the authors. Chen, Bansal, Barthold, Carlson, Veenstra, Basu, Devine, Yun, Ta, and Beal were supported by a training grant from the University of Washington-Allergan Fellowship, unrelated to this work. Basu reports personal fees from Salutis Consulting, unrelated to this work. Graff is an employee of the National Pharmaceutical Council, which was a partner in the development of the CER Collaborative and funding partner for the CMTP RWE Decoder and the GRACE Checklist. A previous version of this work was presented as an invited workshop at AMCP Nexus 2018; October 22-25, 2018; Orlando, FL.


Assuntos
Técnicas de Apoio para a Decisão , Composição de Medicamentos/economia , Preparações Farmacêuticas/economia , Pesquisa Comparativa da Efetividade , Humanos
17.
Int J Psychophysiol ; 156: 10-17, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32679221

RESUMO

Positive affect is linked to greater mental and physiological well-being. Conversely, negative affect is linked to depressive symptoms such as anhedonia. Relative biases in attention to positive or negative emotional information are thought to underlie individual difference in positive and negative affective traits, respectively. Attention bias modification (ABM) increases positive affect by training attention away from negative, or toward positive, stimuli. ABM training to reduce bias to negative information modulates electrocortical activity (i.e., P2, N2, & P3 ERP amplitudes), and this effect is moderated by participant sex. The extent to which ABM training to positive stimuli alters electrocortical activity and the extent to which such changes are moderated by participant sex is unknown. Here, participants completed attend positive ABM (or control) training followed by assessments of attentional bias, mood, and reward-related electrocortical activity. The results provide evidence of greater attentional bias to positive information following ABM. Transfer of these training effects to electrocortical measures was found for the P2 ERP component and moderated by participant sex. Females displayed a larger P2 amplitude for positive outcomes following ABM training. The reward positivity (RewP) and P3 ERPs were not directly affected by training, but the relationship between ERPs was linked to training such that following ABM training, the P2 and RewP components were strongly correlated, while following control training, the P3 and RewP were moderately correlated. Thus, ABM training to positive information enhanced electrocortical measures of reward processing in females and increased the relationship between reward-related ERPs.


Assuntos
Viés de Atenção , Afeto , Viés , Emoções , Feminino , Humanos , Recompensa
18.
Int J Psychophysiol ; 151: 94-102, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32105760

RESUMO

Understanding how emotional stimuli across auditory and visual sensory domains interact and influence multimodal attentional mechanisms is important to understanding how humans prioritize and isolate emotionally-laden stimuli in a continual stream of sensory information that occurs in everyday life. While multimodal emotional human-relevant stimuli have been used in the past, this study is one of the first to look at how human-generated threat-related sounds (e.g., screams) interact with human-generated visual cues of threat (fearful facial expressions) to determine whether these converging sources of threat are represented by either combined or isolated enhancements of visual attention as measured with event-related potential (ERP) components related to attention: the N170, N2, and N2pc. Using the dot-probe task, this study demonstrates that converging sources of multimodal audiovisual threat interact to modulate the N170 ERP component such that auditory distress signals widen the spotlight of attention beyond the contralateral enhancement elicited by the fearful face cue. Multimodal facilitation was neither observed on the N2pc nor the anterior N2. Rather, separate unimodal effects were observed on these ERP components.


Assuntos
Viés de Atenção/fisiologia , Percepção Auditiva/fisiologia , Potenciais Evocados/fisiologia , Reconhecimento Facial/fisiologia , Medo/fisiologia , Percepção Social , Adolescente , Sinais (Psicologia) , Eletroencefalografia , Expressão Facial , Feminino , Humanos , Masculino , Angústia Psicológica , Adulto Jovem
19.
Brain Inj ; 34(3): 363-368, 2020 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-32050803

RESUMO

Primary Objective: Symptoms following concussion commonly include deficits in attentional processing and elevated anxiety. Prioritized allocation of attentional resources to threat-related information is referred to as attentional bias to threat, which is a cardinal symptom - and in some cases a causal factor in the development - of anxiety. Here, we aimed to assess two possibilities regarding the relationship between attentional bias and anxiety in the post-concussive phase of sport-related concussion: (1) attentional bias mediates the relationship between concussion and anxiety or (2) attentional bias and concussion are uniquely associated with anxiety.Research Design: A cross-sectional between-groups design was used to assess differences in anxiety and attentional bias to threat between collegiate athletes with a recent sport-related concussion and a matched control group.Methods and Procedures: Forty-two collegiate athletes, 21 with a sport-related concussion and 21 matched controls, completed the dot-probe task of attentional bias and an anxiety questionnaire.Main Outcomes and Results: Anxiety, but not attentional bias, is elevated in concussion. Additionally, concussion and attentional bias to threat appear to be uniquely associated with anxiety symptoms.Conclusions: Unique treatment/rehabilitation strategies should be considered for individuals with elevated anxiety following concussion.


Assuntos
Ansiedade/etiologia , Traumatismos em Atletas/complicações , Viés de Atenção , Concussão Encefálica/complicações , Esportes , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Adulto Jovem
20.
Motiv Emot ; 44(5): 657-669, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33551518

RESUMO

A new method of calculating attentional bias from the dot-probe task measures fluctuations in bias towards and away from emotional stimuli over time using trial level bias score metrics. We assessed the stability and reliability of traditional attentional bias scores and trial level bias score measures of attentional bias across time in two five-block dot-probe task experiments in non-clinical samples. In experiments 1 and 2, both traditional attentional bias scores and trial level bias score measures of attentional bias did not habituate/decrease across time. In general, trial level bias score metrics (i.e., attention bias variability as well as the mean biases toward and away from threat) were more reliable than the traditional attention bias measure. This pattern was observed across both experiments. The traditional bias score, however, did improve in reliability in the later blocks of the fearful face dot-probe task. Although trial level bias score measures did not habituate and were more reliable across blocks, these measures did not correlate with state or trait anxiety. On the other hand, trial level bias score measures were strongly correlated with general reaction time variability-and after controlling for this effect no longer superior in reliability in comparison to the traditional attention bias measure. We conclude that general response variability should be removed from trial level bias score measures to ensure that they truly reflect attention bias variability.

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