Disrupted prefrontal functional connectivity during post-stress adaption in high ruminators

Abstract

Rumination is a perseverative thinking style that is associated with adverse mental and physical health. Stressful situations have been considered as a trigger for this kind of thinking. Until today, there are mixed findings with respect to the relations of functional connectivity (FC) and rumination. The study at hand aimed to investigate, in how far high and low ruminators would show elevated levels of state rumination after a stress induction and if these changes would show corresponding changes in FC in the cognitive control network (CCN) and dorsal attention network (DAN). 23 high and 22 low trait ruminators underwent resting-state measurements before and after a stress induction with the Trier Social Stress Test (TSST). Changes in rsFC through the TSST were measured with functional near-infrared spectroscopy within and between regions of the CCN. Stress successfully induced state rumination in both groups but stronger in the high trait ruminators. High trait ruminators showed elevated FC within the CCN at baseline, but attenuated increase in FC following the TSST. Increases in FC correlated negatively with state rumination. A lack of FC reactivity within the CCN in high ruminators might reflect reduced network integration between brain regions necessary for emotion regulation and cognitive control.

Neural correlates of mindful emotion regulation in high and low ruminators

“…Importantly, the factor of habitual rumination showed no significant effect, neither in the instruction paradigm nor in the emotion regulation task. In previous investigations using clinical analogue samples, we found encouraging effects in high habitual ruminators, despite the non-clinical groupings 27,62 . In general, it must be noted that reactivity in negative emotion and state rumination were rather low.…”

“…Furthermore, state rumination did not increase during the emotion regulation task in high ruminators, which emphasizes the use of subjectively relevant emotional situations for the induction of state rumination 27,62 . Indeed, in subjectively relevant stress paradigms like those used by our group, the reactive negative emotion and state rumination were much higher than in the current study.…”

“…Cortical activation was measured with a continuous wave, multichannel NIRS system (ETG-4000 Optical Topography System; Hitachi Medical Co., Japan) with a temporal resolution of 10 Hz. The same probeset placement was used as in previous studies of our group on the CCN in rumination 27 , 62 , 69 . It consisted of two frontal and one parietal probeset positioned on an Easycap with sponge rings for additional fixation.…”

“…High ruminators were defined by an RRS mean score higher than 2.25 (percentile > 65), low ruminators by a score lower than 1.8 (percentile < 34). Cut-off criteria were defined as in previous studies in our group 62 , based on comparisons between depressed patients and non-clinical controls 26 (see Supplemental Material Fig. S1).…”

Neuronal correlates of spider phobia in a combined fNIRS-EEG study

“…fNIRS data was assessed as described in previous studies of our group 26 , 43 – 45 . Oxygenated (O 2 Hb) and deoxygenated (HHb) hemoglobin levels (concentration changes) were assessed with a continuous wave, multichannel fNIRS system (ETG-4000 Optical Topography System; Hitachi Medical Co., Japan) with a temporal resolution of 10 Hz.…”