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result(s) for
"Carlson, Joshua"
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Eye-size effects in the dot-probe task: Greater sclera exposure predicts delayed disengagement from fearful faces
2023
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.
Journal Article
The stability and reliability of attentional bias measures in the dot-probe task: Evidence from both traditional mean bias scores and trial-level bias scores
2020
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.
Journal Article
Changing how you look at climate change: attention bias modification increases attention to climate change
by
Voltz, Madeline
,
Carlson, Joshua M
,
Foley, John
in
Air pollution
,
Anthropogenic climate changes
,
Anthropogenic factors
2022
Mitigating the negative impacts of anthropogenic climate change is among the most serious and pressing challenges facing the global community. Despite the severity of the issue, there seems to be a lack of attention paid to climate change in our daily lives. Yet, climate change-related information can capture observers’ attention, and when attention is drawn to a particular environmental risk, the perceived severity of this attended risk is enhanced. The question then is whether attention to climate change-related information can be modified or enhanced. Here, we report the results of two experiments using single-session attention bias modification training procedures designed to increase attentional focus on climate change-related information. In Experiment 1, attention training to emotionally positive images of climate change (e.g., potential solutions such as windmills and solar panels) increased attention to these images, but not emotionally negative images of climate change (e.g., air pollution, natural disasters, and melting ice). In Experiment 2, this effect was replicated. In addition, Experiment 2 revealed that training to emotionally negative images of climate change increased attention to negative images of climate change, and there was a trend for this enhanced attention to generalize to positive images of climate change. Furthermore, attention training towards negative images of climate change enhanced self-reported levels of concern about climate change. Collectively, our results suggest that attention training can increase the allocation of attention to climate change-related information and, under certain training conditions, concern for climate change increases.
Journal Article
Reward dysfunction in major depression: Multimodal neuroimaging evidence for refining the melancholic phenotype
2014
Reward dysfunction is thought to play a core role in the pathophysiology of major depressive disorder (MDD). Event-related potential (ERP) and functional magnetic resonance imaging (fMRI) studies have identified reward processing deficits in MDD, but these methods have yet to be applied together in a single MDD sample. We utilized multimodal neuroimaging evidence to examine reward dysfunction in MDD. Further, we explored how neurobiological reward dysfunction would map onto subtypes of MDD. The feedback negativity (FN), an ERP index of reward evaluation, was recorded in 34 unmedicated depressed individuals and 42 never-depressed controls during a laboratory gambling task. Ventral striatal (VS) activation to reward was recorded in a separate fMRI session, using an identical task, among a subgroup of 24 depressed individuals and a comparison group of 18 non-depressed controls. FN amplitude was blunted in MDD. This effect was driven by a MDD subgroup characterized by impaired mood reactivity to positive events, a core feature of melancholic MDD. A similar pattern was observed for VS activation, which was also blunted among the MDD subgroup with impaired mood reactivity. Neither FN amplitude nor VS activation was related to the full, DSM-defined melancholic or atypical MDD subtypes. Across the MDD sample, FN amplitude and VS activation were correlated, indicating convergence across methods. These results indicate that not all MDD is characterized by reward dysfunction, and that there is meaningful heterogeneity in reward processing within MDD. The current study offers neurobiological evidence that impaired mood reactivity is a key phenotypic distinction for subtyping MDD, and further suggests that the existing melancholic phenotype may require further refinement.
•We empirically link fMRI/ERP measures of abnormal reward processing in depression.•Reward dysfunction was specific to depressed subjects with impaired mood reactivity.•The feedback negativity (FN) ERP and ventral striatal (VS) activation were blunted.•Reward dysfunction was not explained by the full, DSM-defined depression subtypes.•VS activation and FN amplitude were positively correlated in the depressed group.
Journal Article
The NIRS Analysis Package: Noise Reduction and Statistical Inference
2011
Near infrared spectroscopy (NIRS) is a non-invasive optical imaging technique that can be used to measure cortical hemodynamic responses to specific stimuli or tasks. While analyses of NIRS data are normally adapted from established fMRI techniques, there are nevertheless substantial differences between the two modalities. Here, we investigate the impact of NIRS-specific noise; e.g., systemic (physiological), motion-related artifacts, and serial autocorrelations, upon the validity of statistical inference within the framework of the general linear model. We present a comprehensive framework for noise reduction and statistical inference, which is custom-tailored to the noise characteristics of NIRS. These methods have been implemented in a public domain Matlab toolbox, the NIRS Analysis Package (NAP). Finally, we validate NAP using both simulated and actual data, showing marked improvement in the detection power and reliability of NIRS.
Journal Article
Increased attention to climate change mitigation approaches leads to lower levels of climate anxiety
Climate change is a significant threat to both ecosystems and human mental health. Rising awareness of the threats posed by climate change is linked to increased psychological distress, or climate anxiety. While climate anxiety is an adaptive response promoting pro-environmental engagement, heightened and persistent anxiety can impair daily functioning. Traditional anxiety treatments, which target irrational fears, may be inadequate for addressing the rational concerns underlying climate anxiety. Recent research suggests that involvement in collective climate change mitigation efforts may alleviate distress while fostering adaptive engagement. This report investigated whether attention training directed at climate mitigation images reduces climate anxiety. Participants were randomly assigned to attention training or control groups and completed a and post-training assessment of climate anxiety. Results showed significantly lower post-intervention climate anxiety scores in the attention training group compared to the control group—supporting the hypothesis that increased attention to mitigation approaches can reduce climate anxiety. These findings suggest that interventions emphasizing mitigation-focused engagement could provide a novel, proactive approach to managing climate anxiety. Future research should explore long-term outcomes, generalizability to clinical populations, and integration of mitigation-focused strategies in broader mental health interventions.
Journal Article
Neither chimpanzee nor human, Ardipithecus reveals the surprising ancestry of both
2015
Australopithecus fossils were regularly interpreted during the late 20th century in a framework that used living African apes, especially chimpanzees, as proxies for the immediate ancestors of the human clade. Such projection is now largely nullified by the discovery of Ardipithecus. In the context of accumulating evidence from genetics, developmental biology, anatomy, ecology, biogeography, and geology, Ardipithecus alters perspectives on how our earliest hominid ancestors—and our closest living relatives—evolved.
Journal Article
Ventral striatal and medial prefrontal BOLD activation is correlated with reward-related electrocortical activity: A combined ERP and fMRI study
2011
Functional magnetic resonance imaging (fMRI) research suggests that the ventral striatum (VS)/nucleus accumbens, medial prefrontal cortex (mPFC), and broader mesocorticolimbic dopamine system mediate aspects of reward processing from expectation of reward to pleasantness experienced upon reward attainment. In parallel, research utilizing event-related potentials (ERP) indicates that the feedback negativity (FN) is sensitive to reward vs. non-reward feedback and outcome expectation. The FN has been source localized to the mPFC and dorsal striatum, and converging evidence suggests that the FN reflects reward processing in the mesocorticolimbic system. However, the extent to which ERP and fMRI measures of reward processing are correlated has yet to be explored within the same individuals. The primary aim of the current study was to examine the convergence between fMRI (i.e., VS and mPFC) and ERP (i.e., FN) measures of reward processing in forty-two participants who completed counterbalanced fMRI and ERP sessions while performing the same monetary gambling task. For the Win>Loss comparison, fMRI activation in the mesocorticolimbic reward circuit including the VS and mPFC was positively correlated with the FN. Here, we demonstrate that monetary gains activate the VS, mPFC, caudate, amygdala, and orbital frontal cortex, enhance the FN ERP component within 300ms post feedback, and that these measures are related. Thus, fMRI and ERP measures provide complementary information about mesocorticolimbic activity during reward processing, which may be useful in assessing pathological reward sensitivity.
► We empirically link fMRI and ERP measures of reward processing in a single sample. ► The amplitude of the feedback negativity (FN) ERP was enhanced by monetary rewards. ► The ventral striatum (VS) and medial prefrontal cortex (mPFC) were activated by rewards. ► Variability in VS and mPFC BOLD was positively correlated with FN amplitude.
Journal Article
Attentional bias to threat and gray matter volume morphology in high anxious individuals
2022
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.
Journal Article
Sex Differences in Anxiety: An Investigation of the Moderating Role of Sex in Performance Monitoring and Attentional Bias to Threat in High Trait Anxious Individuals
by
Fang, Lin
,
Carlson, Joshua M.
,
Strand, Natalie
in
Anxiety
,
Anxiety disorders
,
attention bias for threat
2021
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.
Journal Article