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

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