Worrying and rumination are both associated with reduced cognitive control.

Persistent negative thought is a hallmark feature of both major depressive disorder and generalized anxiety disorder. Despite its clinical significance, little is known about the underlying mechanisms of persistent negative thought. Recent studies suggest that reduced cognitive control might be an explanatory factor. We investigated the association between persistent negative thought and switching between internal representations in working memory, using the internal shift task (IST). The IST was administered to a group of undergraduates, classified as high-ruminators versus low-ruminators, or high-worriers versus low-worriers. Results showed that high-ruminators and high-worriers have more difficulties to switch between internal representations in working memory as opposed to low-ruminators and low-worriers. Importantly, results were only significant when the negative stimuli used in the IST reflected personally relevant worry themes for the participants. The results of this study indicate that rumination and worrying are both associated with reduced cognitive control for verbal information that is personally relevant.

Depressive symptoms and cognitive control in a mixed antisaccade task: specific effects of depressive rumination.

Growing empirical evidence suggests that cognitive and affective problems in depression may be a reflection of cognitive control impairments. However, to date, the nature of such impairments is still poorly understood and further investigation of this topic is required to advance current knowledge on the underlying vulnerability factors for depression. Using a mixed antisaccade paradigm, the present study examined if depressive symptoms in general, and more specifically rumination, are related to impairments in cognitive control functions such as inhibition and switching. The results on antisaccade latency and error rates indicated that depressive symptoms in general were not related to impairments in inhibition and switching. However, rumination was associated with impaired inhibition such that high, compared to low, ruminators had slower antisaccade latencies. No group differences were observed on antisaccade error rates. Implications for understanding the underlying vulnerability factors for the development of depressive symptoms are discussed.

Rumination is characterized by valence-specific impairments in switching of attention.

The ability to flexibly switch attention between emotional and non-emotional information in working memory is considered important in stress-resilience and is impaired in mood disorders. A recent theory claims that this component of attention is specifically related to ruminative thought. To further investigate this claim we report two new experiments using the internal shift task (IST). In Experiment 1 (N=27) we examined the stability of switching ability measured using the IST through examination of internal consistency (stability within the task) and test-retest-reliability (stability over time) over two weeks. Results indicate relatively high stability of switching ability measured with the IST. In Experiment 2 the IST was administered to a pre-selected undergraduate sample of high (N=20) and low ruminators (N=20). The main findings were that rumination was related to attentional switching impairments, specifically in the context of emotional information. The switching impairments were most pronounced when negative information was held in working memory. The attentional switching impairments were most strongly related to the depressive brooding component of rumination. The results of this study lend further support to the proposed link between rumination and switching abilities.

Rumination mediates the relationship between impaired cognitive control for emotional information and depressive symptoms: A prospective study in remitted depressed adults.

Impaired cognitive control may be an important vulnerability factor for depression. Moreover, impairments in cognitive control have been proposed as a crucial process underlying ruminative thinking. The present study investigates the influence of impaired cognitive control for emotional information on rumination and depressive symptoms in a prospective design with a 1 year follow up in a clinical sample. Thirty remitted depressed adults completed the Internal Shift Task (IST), a measure of cognitive control of emotional information, at baseline. Moreover, questionnaires measuring rumination (RRS) and depressive symptoms (BDI-II) were administered. One year later participants were contacted again and asked to complete the BDI-II and RRS. Mediation analyses showed a significant influence of impaired cognitive control for emotional information at baseline on depressive symptoms one year later, which was fully mediated by rumination. These findings underscore the importance of cognitive control abilities as a process underlying rumination and as a vulnerability factor for depression. They can stimulate translational research to improve the effectiveness of interventions that aim to decrease vulnerability by targeting cognitive control.

Internal cognitive control in clinical depression: general but no emotion-specific impairments.

Prior research has suggested that depression is characterized by impaired cognitive control. The present study sought to investigate internal cognitive control impairments related to emotional information and task settings in clinical depression (MDD, major depressive disorder). Internal cognitive control was operationalized as switching between internally held mental representations that required continuous updating in working memory and measured with the Internal Shift Task (IST). The results showed that MDD individuals were characterized by a general switching impairment. This switching impairment was neither influenced by the task-relevance of emotional information, nor influenced by the valence of the faces within the emotion condition. The impairment in cognitive control reflected in general switching impairments was related to rumination, a specific cognitive symptom and important risk factor of depression. The results of this study offer new insights into the relationship between depression and impaired cognitive control with potential clinical implications, informing treatment and prevention programmes.

Cognitive control moderates the association between stress and rumination.

BACKGROUND AND OBJECTIVES: A prospective design was used to examine whether inter-individual differences in cognitive control ability, for non-emotional and emotional material, play a moderating role in the association between the occurrence of a stressful event and the tendency to ruminate. METHODS: At baseline, the Internal Switch Task (IST) was administered in an undergraduate sample to measure the ability to switch attention between items held in working memory. Six weeks after baseline, self-report questionnaires were administered at 4 fixed moments during their first examination period at university, measuring stressors, rumination and depressive symptoms. RESULTS: Results revealed that impaired cognitive control, reflected in larger switch costs, moderated the association between stress and increased rumination. Interestingly, a larger switch cost when processing emotional material was specifically associated with increased depressive brooding in response to stress. No effects with reflective pondering were observed. CONCLUSIONS: Implications for understanding the underlying mechanisms of rumination are discussed.

Understanding depressive rumination from a cognitive science perspective: the impaired disengagement hypothesis.

Persisting negative thoughts are considered a hallmark of depression. Recent information-processing approaches have begun to uncover underlying mechanisms of depressive rumination. Despite marked advances in this area, there is a lack of integration between psychopathology and cognitive (neuro) science research. We propose the 'impaired disengagement' hypothesis as a unifying framework between both approaches. The core tenet of our model is that prolonged processing of self-referent material is due to impaired attentional disengagement from negative self-referent information. We discuss empirical evidence for this framework and outline future ways in which the causal predictions of this model can be tested. The proposed framework can account for effectiveness of various treatments for depression and may aid in devising new interventions to target depressive cognition.

Mood-congruent attention and memory bias in dysphoria: Exploring the coherence among information-processing biases.

Recent studies indicate that depression is characterized by mood-congruent attention bias at later stages of information-processing. Moreover, depression has been associated with enhanced recall of negative information. The present study tested the coherence between attention and memory bias in dysphoria. Stable dysphoric (n = 41) and non-dysphoric (n = 41) undergraduates first performed a spatial cueing task that included negative, positive, and neutral words. Words were presented for 250 ms under conditions that allowed or prevented elaborate processing. Memory for the words presented in the cueing task was tested using incidental free recall. Dysphoric individuals exhibited an attention bias for negative words in the condition that allowed elaborate processing, with the attention bias for negative words predicting free recall of negative words. Results demonstrate the coherence of attention and memory bias in dysphoric individuals and provide suggestions on the influence of attention bias on further processing of negative material.