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1.
PeerJ ; 12: e17262, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737738

RESUMO

Although exposure-based therapy has been found to be effective at alleviating symptoms of social anxiety disorder, it often does not lead to full remission, and relapse after treatment is common. Exposure therapy is based on theoretical principles of extinction of conditioned fear responses. However, there are inconsistencies in findings across experiments that have investigated the effect of social anxiety on threat conditioning and extinction processes. This systematic review and meta-analysis aimed to examine whether elevated levels of social anxiety are associated with abnormalities in threat conditioning and extinction processes. A second aim was to examine the sensitivity of various study designs and characteristics to detect social anxiety-related differences in threat conditioning and extinction. A systematic search was conducted, which identified twenty-three experiments for inclusion in the review. The findings did not demonstrate compelling evidence that high levels of social anxiety are associated with atypical threat conditioning or extinction. Further, when systematically examining the data, there was no convincing support that the use of a particular psychophysiological measure, subjective rating, or experimental parameter yields more consistent associations between social anxiety and conditioning processes during threat acquisition or extinction. Meta-analyses demonstrated that during threat extinction, the use of anxiety ratings as a dependent variable, socially relevant unconditioned stimuli, and a higher reinforcement schedule produced more detectable effects of social anxiety on compromised extinction processes compared to any other dependent variable (subjective or physiological) or experimental parameter. Overall, the results of this study suggest that social anxiety is not reliably related to deficits in conditioning and extinction processes in the context of laboratory-based Pavlovian conditioning paradigms.


Assuntos
Extinção Psicológica , Medo , Fobia Social , Humanos , Medo/psicologia , Fobia Social/psicologia , Ansiedade/psicologia , Condicionamento Clássico
2.
Front Neurosci ; 17: 1070413, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816136

RESUMO

Quality control is a critical step in the processing and analysis of functional magnetic resonance imaging data. Its purpose is to remove problematic data that could otherwise lead to downstream errors in the analysis and reporting of results. The manual inspection of data can be a laborious and error-prone process that is susceptible to human error. The development of automated tools aims to mitigate these issues. One such tool is pyfMRIqc, which we previously developed as a user-friendly method for assessing data quality. Yet, these methods still generate output that requires subjective interpretations about whether the quality of a given dataset meets an acceptable standard for further analysis. Here we present a quality control protocol using pyfMRIqc and assess the inter-rater reliability of four independent raters using this protocol for data from the fMRI Open QC project (https://osf.io/qaesm/). Data were classified by raters as either "include," "uncertain," or "exclude." There was moderate to substantial agreement between raters for "include" and "exclude," but little to no agreement for "uncertain." In most cases only a single rater used the "uncertain" classification for a given participant's data, with the remaining raters showing agreement for "include"/"exclude" decisions in all but one case. We suggest several approaches to increase rater agreement and reduce disagreement for "uncertain" cases, aiding classification consistency.

3.
Autism ; 25(6): 1615-1626, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33706553

RESUMO

LAY ABSTRACT: One behaviour often observed in individuals with autism is that they tend to look less towards social stimuli relative to neurotypical individuals. For instance, many eye-tracking studies have shown that individuals with autism will look less towards people and more towards objects in scenes. However, we currently know very little about how these behaviours change over time. Tracking these moment-to-moment changes in looking behaviour in individuals with autism can more clearly illustrate how they respond to social stimuli. In this study, adults with and without autism were presented with displays of social and non-social stimuli, while looking behaviours were measured by eye-tracking. We found large differences in how the two groups looked towards social stimuli over time. Neurotypical individuals initially showed a high probability of looking towards social stimuli, then a decline in probability, and a subsequent increase in probability after prolonged viewing. By contrast, individuals with autism showed an initial increase in probability, followed by a continuous decline in probability that did not recover. This pattern of results may indicate that individuals with autism exhibit reduced responsivity to the reward value of social stimuli. Moreover, our data suggest that exploring the temporal nature of gaze behaviours can lead to more precise explanatory theories of attention in autism.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Adulto , Atenção , Fixação Ocular , Humanos , Probabilidade
4.
Autism Res ; 14(2): 289-300, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32686920

RESUMO

Behavioral studies indicate that autistic traits predict reduced gaze toward social stimuli. Moreover, experiments that require participants to make an explicit choice between stimuli indicate reduced preferences for social stimuli in individuals with high autistic traits. These observations, in combination, fit with the idea that gaze is actively involved in the formation of choices-gaze toward a stimulus increases the likelihood of its subsequent selection. Although these aspects of gaze and choice behavior have been well characterized separately, it remains unclear how autistic traits affect the relationship between gaze and socially relevant choices. In a choice-based eye-tracking paradigm, we observed that autistic traits predict less frequent and delayed selection of social stimuli. Critically, eye tracking revealed novel phenomena underlying these choice behaviors: first, the relationship between gaze and choice behavior was weaker in individuals with high autistic traits-an increase in gaze to a stimulus was associated with a smaller increase in choice probability. Second, time-series analyses revealed that gaze became predictive of choice behaviors at longer latencies in observers with high autistic traits. This dissociation between gaze and choice in individuals with high autistic traits may reflect wider atypicalities in value coding. Such atypicalities may predict the development of atypical social behaviors associated with the autism phenotype. LAY SUMMARY: When presented with multiple stimuli to choose from, we tend to look more toward the stimuli we later choose. Here, we found that this relationship between looking and choosing was reduced in individuals with high autistic traits. These data indicate that autistic traits may be associated with atypical processing of value, which may contribute to the reduced preferences for social stimuli exhibited by individuals with autism.


Assuntos
Transtorno Autístico , Transtorno Autístico/complicações , Fixação Ocular , Humanos , Comportamento Social
5.
Neurosci Biobehav Rev ; 119: 376-395, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33069686

RESUMO

Social motivation accounts of autism spectrum disorder (ASD) posit that individuals with ASD find social stimuli less rewarding than neurotypical (NT) individuals. Behaviorally, this is proposed to manifest in reduced social orienting (individuals with ASD direct less attention towards social stimuli) and reduced social seeking (individuals with ASD invest less effort to receive social stimuli). In two meta-analyses, involving data from over 6000 participants, we review the available behavioral studies that assess social orienting and social seeking behaviors in ASD. We found robust evidence for reduced social orienting in ASD, across a range of paradigms, demographic variables and stimulus contexts. The most robust predictor of this effect was interactive content - effects were larger when the stimulus involved an interaction between people. By contrast, the evidence for reduced social seeking indicated weaker evidence for group differences, observed only under specific experimental conditions. The insights gained from this meta-analysis can inform design of relevant task measures for social reward responsivity and promote directions for further study on the ASD phenotype.


Assuntos
Transtorno do Espectro Autista , Atenção , Humanos , Motivação , Recompensa , Comportamento Social
6.
J Exp Psychol Hum Percept Perform ; 45(6): 790-802, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30998068

RESUMO

The visual probe (VP) paradigm provides evidence that emotional stimuli attract attention. Such effects have been reported even when stimuli are presented outside of awareness. These findings have shaped the idea that humans possess a processing pathway that detects evolutionarily significant signals independently of awareness. Here, we addressed 2 unresolved questions: First, if emotional stimuli attract attention, is this driven by their affective content, or by low-level image properties (e.g., luminance contrast)? Second, does attentional capture occur under conditions of genuine unawareness? We found that observers preferentially allocated attention to emotional faces under aware viewing conditions. However, this effect was best explained by low-level stimulus properties, rather than emotional content. When stimuli were presented outside of awareness (via continuous flash suppression or masking), we found no evidence that attention was directed toward emotional face stimuli. Finally, observer's awareness of the stimuli (assessed by d') predicted attentional cuing. Our data challenge existing literature: First, we cast doubt on the notion of preferential attention to emotional stimuli in the absence of awareness. Second, we question whether effects revealed by the VP paradigm genuinely reflect emotion-sensitive processes, instead suggesting they can be more parsimoniously explained by low-level variability between stimuli. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Atenção/fisiologia , Conscientização/fisiologia , Emoções/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Percepção Social , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
8.
Neurosci Biobehav Rev ; 96: 290-301, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30355521

RESUMO

The motion aftereffect (MAE) provides a behavioural probe into the mechanisms underlying motion perception, and has been used to study the effects of attention on motion processing. Visual attention can enhance detection and discrimination of selected visual signals. However, the relationship between attention and motion processing remains contentious: not all studies find that attention increases MAEs. Our meta-analysis reveals several factors that explain superficially discrepant findings. Across studies (37 independent samples, 76 effects) motion adaptation was significantly and substantially enhanced by attention (Cohen's d = 1.12, p < .0001). The effect more than doubled when adapting to translating (vs. expanding or rotating) motion. Other factors affecting the attention-MAE relationship included stimulus size, eccentricity and speed. By considering these behavioural analyses alongside neurophysiological work, we conclude that feature-based (rather than spatial, or object-based) attention is the biggest driver of sensory adaptation. Comparisons between naïve and non-naïve observers, different response paradigms, and assessment of 'file-drawer effects' indicate that neither response bias nor publication bias are likely to have significantly inflated the estimated effect of attention.


Assuntos
Adaptação Psicológica , Atenção , Percepção de Movimento , Adaptação Fisiológica , Animais , Humanos , Psicofísica
9.
Proc Biol Sci ; 285(1893): 20181716, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30963898

RESUMO

Individuals with low empathy often show reduced attention towards social stimuli. A limitation of this literature is the lack of empirical work that has explicitly characterized how this relationship manifests itself over time. We investigate this issue by analysing data from two large eye-tracking datasets (total n = 176). Via growth-curve analysis, we demonstrate that self-reported empathy (as measured by the empathy quotient-EQ) predicts the temporal evolution of gaze behaviour under conditions where social and non-social stimuli compete for attention. In both datasets, we found that EQ not only predicted a global increase in social attention, but predicted a different temporal profile of social attention. Specifically, we detected a reliable effect of empathy on gaze towards social images after prolonged viewing. An analysis of switch latencies revealed that low-EQ observers switched gaze away from an initially fixated social image more frequently and at earlier latencies than high-EQ observers. Our analyses demonstrate that modelling these temporal components of gaze signals may reveal useful behavioural phenotypes. The explanatory power of this approach may provide enhanced biomarkers for conditions marked by deficits in empathy-related processes.


Assuntos
Atenção , Empatia , Relações Interpessoais , Adulto , Feminino , Humanos , Masculino , Autorrelato , Adulto Jovem
10.
Psychol Bull ; 142(9): 934-968, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27123863

RESUMO

Given capacity limits, only a subset of stimuli give rise to a conscious percept. Neurocognitive models suggest that humans have evolved mechanisms that operate without awareness and prioritize threatening stimuli over neutral stimuli in subsequent perception. In this meta-analysis, we review evidence for this 'standard hypothesis' emanating from 3 widely used, but rather different experimental paradigms that have been used to manipulate awareness. We found a small pooled threat-bias effect in the masked visual probe paradigm, a medium effect in the binocular rivalry paradigm and highly inconsistent effects in the breaking continuous flash suppression paradigm. Substantial heterogeneity was explained by the stimulus type: the only threat stimuli that were robustly prioritized across all 3 paradigms were fearful faces. Meta regression revealed that anxiety may modulate threat-biases, but only under specific presentation conditions. We also found that insufficiently rigorous awareness measures, inadequate control of response biases and low level confounds may undermine claims of genuine unconscious threat processing. Considering the data together, we suggest that uncritical acceptance of the standard hypothesis is premature: current behavioral evidence for threat-sensitive visual processing that operates without awareness is weak. (PsycINFO Database Record


Assuntos
Conscientização , Medo , Inconsciente Psicológico , Percepção Visual , Ansiedade , Viés , Expressão Facial , Reconhecimento Facial , Humanos
11.
J Exp Psychol Hum Percept Perform ; 41(6): 1748-57, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26280260

RESUMO

Only a subset of visual signals give rise to a conscious percept. Threat signals, such as fearful faces, are particularly salient to human vision. Research suggests that fearful faces are evaluated without awareness and preferentially promoted to conscious perception. This agrees with evolutionary theories that posit a dedicated pathway specialized in processing threat-relevant signals. We propose an alternative explanation for this "fear advantage." Using psychophysical data from continuous flash suppression (CFS) and masking experiments, we demonstrate that awareness of facial expressions is predicted by effective contrast: the relationship between their Fourier spectrum and the contrast sensitivity function. Fearful faces have higher effective contrast than neutral expressions and this, not threat content, predicts their enhanced access to awareness. Importantly, our findings do not support the existence of a specialized mechanism that promotes threatening stimuli to awareness. Rather, our data suggest that evolutionary or learned adaptations have molded the fearful expression to exploit our general-purpose sensory mechanisms.


Assuntos
Conscientização/fisiologia , Expressão Facial , Medo , Comportamento Social , Percepção Visual/fisiologia , Feminino , Humanos , Masculino
12.
Neurosci Biobehav Rev ; 57: 46-62, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26232699

RESUMO

BACKGROUND: Transcranial direct current stimulation (tDCS) is a potential alternative treatment option for major depressive episodes (MDE). OBJECTIVES: We address the efficacy and safety of tDCS in MDE. METHODS: The outcome measures were Hedges' g for continuous depression ratings, and categorical response and remission rates. RESULTS: A random effects model indicated that tDCS was superior to sham tDCS (k=11, N=393, g=0.30, 95% CI=[0.04, 0.57], p=0.027). Adjunctive antidepressant medication and cognitive control training negatively impacted on the treatment effect. The pooled log odds ratios (LOR) for response and remission were positive, but statistically non-significant (response: k=9, LOR=0.36, 95% CI[-0.16, 0.88], p=0.176, remission: k=9, LOR=0.25, 95% CI [-0.42, 0.91], p=0.468). We estimated that for a study to detect the pooled continuous effect (g=0.30) at 80% power (alpha=0.05), a total N of at least 346 would be required (with the total N required to detect the upper and lower bound being 49 and 12,693, respectively). CONCLUSIONS: tDCS may be efficacious for treatment of MDE. The data do not support the use of tDCS in treatment-resistant depression, or as an add-on augmentation treatment. Larger studies over longer treatment periods are needed.


Assuntos
Transtorno Depressivo Maior/terapia , Avaliação de Resultados em Cuidados de Saúde/métodos , Estimulação Transcraniana por Corrente Contínua/métodos , Humanos , Estimulação Transcraniana por Corrente Contínua/efeitos adversos
13.
J Exp Psychol Hum Percept Perform ; 41(3): 798-806, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25867508

RESUMO

The rapid detection and evaluation of threat is of fundamental importance for survival. Theories suggest that this evolutionary pressure has driven functional adaptations in a specialized visual pathway that evaluates threat independently of conscious awareness. This is supported by evidence that threat-relevant stimuli rendered invisible by backward masking can induce physiological fear responses and modulate spatial attention. The validity of these findings has since been questioned by research using stringent, objective measures of awareness. Here, we use a modified continuous flash suppression paradigm to ask whether threatening images induce adaptive changes in autonomic arousal, attention, or perception when presented outside of awareness. In trials where stimuli broke suppression to become visible, threatening stimuli induced a significantly larger skin conductance response than nonthreatening stimuli and attracted spatial attention over scrambled images. However, these effects were eliminated in trials where observers were unaware of the stimuli. In addition, concurrent behavioral data provided no evidence that threatening images gained prioritized access to awareness. Taken together, our data suggest that the evaluation and spatial detection of visual threat are predicted by awareness.


Assuntos
Nível de Alerta , Atenção , Conscientização , Medo , Percepção Visual , Nível de Alerta/fisiologia , Atenção/fisiologia , Conscientização/fisiologia , Medo/psicologia , Feminino , Resposta Galvânica da Pele/fisiologia , Humanos , Masculino , Estimulação Luminosa
14.
Emotion ; 13(3): 537-44, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23398580

RESUMO

Threat-relevant stimuli such as fear faces are prioritized by the human visual system. Recent research suggests that this prioritization begins during unconscious processing: A specialized (possibly subcortical) pathway evaluates the threat relevance of visual input, resulting in preferential access to awareness for threat stimuli. Our data challenge this claim. We used a continuous flash suppression (CFS) paradigm to present emotional face stimuli outside of awareness. It has been shown using CFS that salient (e.g., high contrast) and recognizable stimuli (faces, words) become visible more quickly than less salient or less recognizable stimuli. We found that although fearful faces emerge from suppression faster than other faces, this was wholly explained by their low-level visual properties, rather than their emotional content. We conclude that, in the competition for visual awareness, the visual system prefers and promotes unconscious stimuli that are more "face-like," but the emotional content of a face has no effect on stimulus salience.


Assuntos
Conscientização/fisiologia , Emoções/fisiologia , Expressão Facial , Percepção Social , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
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