38 research outputs found
BOLD Signal Variability Patterns in Neural Correlates of Reflection and Brooding Components of Rumination
Researchers have established that rumination is a debilitating symptom that positively correlates with symptoms of depression. Rumination involves self-focused attention, often negative, as a means of coping with a depressed mood or sadness. The Ruminative Responses Scale (RRS) is a tool used to measure rumination severity that includes two subsets of rumination: brooding and reflection. Brooding rumination is related to passive and judgmental thoughts about one’s circumstances and is therefore associated with higher levels of past and current depression. Although brooding is thought to be a maladaptive response to feelings of depression, past studies suggest that the reflection subtype may act in an adaptive way as it is a problem-solving mechanism and has shown to lead to a decrease in depression duration. The present study seeks to identify brain mechanisms associated with rumination and brooding subtypes to explore why some people exhibit one over the other. Specifically, this study will examine the blood-oxygen level dependent signal variability (BOLD-SV) patterns within brain regions thought to be associated with rumination subtypes in relation to depression, which has yet to be analyzed in the literature. A sample of 79 women were recruited to complete a resting-state fMRI scan, RRS, and a depression symptom measure. The first aim of this study was to identify BOLD-SV differences between regions of interest (ROIs) implicated in reflection and brooding, and we hypothesized that (1) reflection and brooding subtypes will show distinct correlations with BOLD-SV in neural ROIs implicated in rumination. The second aim of this study was to determine whether there are differences in BOLD-SV of the neural regions associated with reflection and brooding based on depression history. Consistent with this aim, we predicted that there would be (1) lower BOLD-SV in ROIs associated with brooding for the currently-depressed group and (2) higher BOLD-SV in ROIs associated with reflection for both the past depression and no depression group. In accordance with the first aim, this study found a significant effect of rumination subtype on BOLD-SV in the dlPFC, (F3,75 = 4.86, p = .005). Specifically, greater levels of brooding were associated with lower BOLD-SV in the dlPFC, (t(78) = -2.612, p = .01). In support of our first hypothesis under our second aim, significantly reduced BOLD-SV was found in the dlPFC for the currently-depressed group as compared with the no depression group (t(63) = -2.436, p = .018). This study discusses the implications of these results and suggests directions for future studies to strengthen the findings of this foundational research
Damage to Association Fiber Tracts Impairs Recognition of the Facial Expression of Emotion
An array of cortical and subcortical structures have been implicated in the recognition of emotion from facial expressions. It remains unknown how these regions communicate as parts of a system to achieve recognition, but white matter tracts are likely critical to this process. We hypothesized that (1) damage to white matter tracts would be associated with recognition impairment and (2) the degree of disconnection of association fiber tracts [inferior longitudinal fasciculus (ILF) and/or inferior fronto-occipital fasciculus (IFOF)] connecting the visual cortex with emotion-related regions would negatively correlate with recognition performance. One hundred three patients with focal, stable brain lesions mapped onto a reference brain were tested on their recognition of six basic emotional facial expressions. Association fiber tracts from a probabilistic atlas were coregistered to the reference brain. Parameters estimating disconnection were entered in a general linear model to predict emotion recognition impairments, accounting for lesion size and cortical damage. Damage associated with the right IFOF significantly predicted an overall facial emotion recognition impairment and specific impairments for sadness, anger, and fear. One subject had a pure white matter lesion in the location of the right IFOF and ILF. He presented specific, unequivocal emotion recognition impairments. Additional analysis suggested that impairment in fear recognition can result from damage to the IFOF and not the amygdala. Our findings demonstrate the key role of white matter association tracts in the recognition of the facial expression of emotion and identify specific tracts that may be most critical
Chronic Stress in Relation to Locus of Control
Stress is prominent in everyone’s lives, and if the right precautions are not taken, stress can become chronic and harmful to an individual’s health (Schmitz, Neumann, & Oppermann, 2000). To prevent chronic stress, researchers seek to find out important factors that lead to chronic stress. One of the most prominent factors leading to chronic stress is locus of control (LOC), or how much control people feel they have over situations (Cummins, 1988). People can endorse an internal locus of control which means individual attributes events occurring in their life to their own behavior, or an external, which one would consider an outside force responsible for an event that occurred in their life (Bollini, Walker, Hamann, & Kestler, 2004). There are mixed results in the literature regarding different forms of stress and locus of control. Some results indicate that external locus of control is related to higher stress levels (Schmitz et al. 2000), some results indicate that a more internal locus of control is related to higher stress (Cummins, 1988), while others found no significant relationship (Bollini et al. 2004). For this experiment, researchers wanted to examine the relationship between type of locus of control and amount of chronic stress. It was predicted that greater external locus of control would be associated with increased chronic stress. In the present study, UMSL students (n=81) completed the Life Stressors Checklist to measure amount of stress exposure, as well as the Locus of Control Scale to measure if participants had more internal or external locus of control. We found that LOC was not correlated with levels of chronic stress (F(1,79)=0.049, p\u3e0.05). Although a significant relationship was not found, it is still important that individuals learn to manage stress, because stress presents itself similarly, no matter which perception of control an individual possesses (Bollini et al. 2004)
Stress, Resilience, and Impulsivity
Stress is a phenomenon that everyone will experience. Stress that is unmanageable can become chronic, which is linked to various negative psychological effects (Le Fevre, Matheny, & Kolt, 2003). Although stress research often focuses on the negative long-term effects, there are times where individuals develop a trait known as resilience. Resilient individuals eventually learn how to buffer the negative effects of stress (Cicchetti, 2010), and researchers have begun investigating the positive effects of resilience on stress (Cicchetti, 2010; Kermott, Johnson, Sood, R., Jenkins, & Sood, A., 2019). Currently, few studies have been conducted to identify any additional traits that may impact the relationship between stress and resilience. However, there is some evidence that impulsivity may be a prevalent trait that affects the dynamic between stress and resilience. Typically, stressed individuals exhibit higher levels of impulsivity (Moustafa, Tindle, Frydecka, & Misiak, 2017). In turn, this may affect one’s level of resilience. The present study aims to focus on the relationship between stress (current and chronic) and resilience, as well as the moderating effect of impulsivity on that relationship. It was predicted that there would be a relationship between stress and resilience and that impulsivity would have a moderating effect on the relationship. UMSL students (n=81) completed various questionnaires to determine their stress, resilience, and impulsivity levels. We found that chronic stress was not a significant predictor of resilience (R2 = .52, F(1,79) = .40, p \u3e .05), but that current stress was a significant predictor (R2= .15, F(1,79) = 13.4, p \u3c .001). For this presentation, we decided to only run one moderation with the significant results. We found that impulsivity was not a significant moderator between current stress and resilience (B = -.02, p \u3e .05). Although we did not find a significant relationship within the moderation, there is still some value in investigating traits that influence stress and resilience. Understanding potential factors that may impact resilience may help researchers identify appropriate methods for increasing resilience in vulnerable populations
The Relationship Between Self-Focus and Anxiety
Researchers have linked self-focus with multiple psychological disorders and forms of maladaptive cognition, such as anxiety and depression. Throughout their lifetime, around 33% of U.S. adults suffer from an anxiety disorder, making it the most prevalent mental illness in the country. Anxiety symptoms often co-occur with depressive symptoms, therefore depression and anxiety are often consolidated together in research scenarios. Past studies have shown a positive correlation between negative self-focus and depressive symptoms. However, with anxiety prevalence on the rise, it is worthy of attention independent from depression. This study will look at the relationship between anxiety and negative self-focus. Previous research has shown that anxiety is correlated with higher reports of self-focus, and more severe levels of anxiety are related to negative self-focus specifically. The present study examines self-focused responses on a language task in relation to anxiety. Additionally, this study will consider whether depression mediates the relationship between anxiety and negative self-focus, which has yet to be analyzed in the literature. The Sentence Completion Task (SCT) is an open-ended language task that typically provides participants with beginnings of sentences, known as stems , and participants then complete the sentences in ways that are meaningful to them. Responses to the SCT are coded for focus (e.g.. self, other, both, or neither) and valence (positive, negative, or neutral). A sample of 188 college students were recruited to complete the SCT and the Beck Anxiety Inventory (BAI). This study predicted that (1) a positive correlation exists between anxiety symptoms and amount of self-focus, (2) negative self-focus is related to higher anxiety levels, and (3) there will be a strong correlation between anxiety and negative self-focus once depression is controlled for. Interestingly, our results showed that anxiety did not correlate with self-focus (r(155)=.121, p=.130) or negative self-focus (r(155)=.071, p=.375), which does not support findings from previous studies. Since the results from our first two hypotheses were not significant, we did not test the correlation between anxiety and negative self-focus while controlling for depression. This study discusses possible reasons behind the non-significant findings, and suggests that future research could evaluate if anxiety has a strong relationship with external-focused attention
The Dimensional Relationship Between Age of First Traumatic Exposure and Perceptions of Control: A Pilot Study
An earlier age of onset of trauma (before 16 years old) has been associated with greater psychological impairments, such as increased risk of psychopathology and greater psychological distress in adulthood (Kaplow & Widom, 2007; Mueller et al., 2010; Teicher et al., 2009). Furthermore, trauma exposure has been linked to deficits in control (Fraizer, 2003; Ataria, 2015). However, the association between age of first trauma and perception of control are unclear. The present study aimed to define the relationship between age of first trauma and perception of control, or self-agency. Self-agency is defined as the sense of control of one’s actions and/or thoughts (Gallagher, 2000). Participants (n = 14, Mage = 24.00 ± 9.54; Male = 2) first completed online questionnaires which examined exposure to traumatic and stressful events (e.g. jail time, neglect, and natural disasters) and measures relating to psychopathologies (i.e. depression, anxiety, and posttraumatic stress disorder (PTSD)). Participants then completed a computer based Self-agency Judgement Task, where they were asked to rate their perceived control after moving a box on the computer in various noise conditions (0%, 30%, 75%, 90%, 100%). Preliminary results show that there were statistically significant differences between age of trauma and agency ratings, such that earlier age of trauma predicted lower ratings of average control within all five conditions, t(12) = -2.30, p = .040. Interestingly, earlier age of trauma did not predict depression (t(12) = -1.06, p = .311), anxiety (t(12) = -1.06, p = .312), or PTSD psychopathology scores (t(12) = -0.02, p = .981). As data collection is ongoing, we will continue to examine the relationship between age of first trauma and perceptions of control, and its relationship to psychological disorders
The Relationship Between Resilience, Stress & PTSD
Post-traumatic stress disorder (PTSD) is characterized by intrusive thoughts or memories of the traumatic event that hinder daily life activities of individuals with a PTSD diagnosis. Stress exposure has further been shown to exacerbate PTSD symptoms. Given that resilience has been shown to buffer levels of stress, the current study investigated whether resilience may moderate the relationship between stress and PTSD symptoms. Eighty-one participants over the age of 18 were recruited from the University of Missouri-Saint Louis and St. Louis community. Participants completed 3 self-report measures of resilience, exposure to stressful life events (e.g., Have you ever been in a car accident before?), and PTSD symptoms. In support our first hypothesis, we found that stress exposure was associated with greater PTSD symptoms (b = 2.08, t(77) = 5.02, p \u3c .001). However, resilience did not moderate the relationship between stress exposure and PTSD symptoms (B = -0.01, p = .68). Future studies may examine the influence of medications on PTSD, chronic stress, and resilience
The Influence of Anhedonic Symptom Severity on dmPFC Connectivity in PTSD
This study examined resting state functional connectivity (rsFC) of the dorsal medial prefrontal cortex ( dmPFC ) as a function of anhedonia in individuals with posttraumatic stress disorder (PTSD). Results showed that anhedonia positively correlated with hyperconnectivity between the dmPFC and the left retrosplenial cortex. These findings support that anhedonia is associated with increased rsFC within the default mode network (DMN) for PTSD
Altered Resting-State Functional Connectivity in Cortical Networks in Psychopathy
Psychopathy is a personality disorder characterized by callous antisocial behavior and criminal recidivism. Here we examine whether psychopathy is associated with alterations in functional connectivity in three large-scale cortical networks. Using fMRI in 142 adult male prison inmates, we computed resting-state functional connectivity using seeds from the default mode network, frontoparietal network, and cingulo-opercular network. To determine the specificity of our findings to these cortical networks, we also calculated functional connectivity using seeds from two comparison primary sensory networks: visual and auditory networks. Regression analyses related network connectivity to overall psychopathy scores and to subscores for the “factors” and “facets” of psychopathy: Factor 1, interpersonal/affective traits; Factor 2, lifestyle/antisocial traits; Facet 1, interpersonal; Facet 2, affective; Facet 3, lifestyle; Facet 4, antisocial. Overall psychopathy severity was associated with reduced functional connectivity between lateral parietal cortex and dorsal anterior cingulate cortex. The two factor scores exhibited contrasting relationships with functional connectivity: Factor 1 scores were associated with reduced functional connectivity in the three cortical networks, whereas Factor 2 scores were associated with heightened connectivity in the same networks. This dissociation was evident particularly in the functional connectivity between anterior insula and dorsal anterior cingulate cortex. The facet scores also demonstrated distinct patterns of connectivity. We found no associations between psychopathy scores and functional connectivity within visual or auditory networks. These findings provide novel evidence on the neural correlates of psychopathy and suggest that connectivity between cortical association hubs, such as the dorsal anterior cingulate cortex, may be a neurobiological marker of the disorder
Damage to the default mode network disrupts autobiographical memory retrieval
International audienceFunctional neuroimaging studies have implicated the default mode network (DMN) in autobiographical memory (AM). Convergent evidence from a lesion approach would help clarify the role of the DMN in AM. In this study, we used a voxelwise lesion-deficit approach to test the hypothesis that regions of the DMN are necessary for AM. We also explored whether the neural correlates of semantic AM (SAM) and episodic AM (EAM) were overlapping or distinct. Using the Iowa Autobiographical Memory Questionnaire, we tested AM retrieval in 92 patients with focal, stable brain lesions. In support of our hypothesis, damage to regions within the DMN (medial prefrontal cortex, mPFC; posterior cingulate cortex, PCC; inferior parietal lobule, IPL; medial temporal lobe, MTL) was associated with AM impairments. Within areas of effective lesion coverage, the neural correlates of SAM and EAM were largely distinct, with limited areas of overlap in right IPL. Whereas SAM deficits were associated with left mPFC and MTL damage, EAM deficits were associated with right mPFC and MTL damage. These results provide novel neuropsychological evidence for the necessary role of parts of the DMN in AM. More broadly, the findings shed new light on how the DMN participates in self-referential processing