No evidence from a negative mood induction fMRI task for frontal functional asymmetry as a suitable neurofeedback target.

Frontal functional asymmetry (FA) has been proposed as a potential target for neurofeedback (NFB) training for mental disorders but most FA NFB studies used electroencephalography while the investigations of FA NFB in functional magnetic resonance imaging (fMRI) are rather limited. In this study, we aimed at identifying functional asymmetry effects in fMRI and exploring its potential as a target for fMRI NFB studies by re-analyzing an existing data set containing a resting state measurement and a sad mood induction task of n = 30 participants with remitted major depressive disorder and n = 30 matched healthy controls. We applied low-frequency fluctuations (ALFF), fractional ALFF, and regional homogeneity and estimated functional asymmetry in both a voxel-wise and regional manner. We assessed functional asymmetry during rest and negative mood induction as well as functional asymmetry changes between the phases, and associated the induced mood change with the change in functional asymmetry. Analyses were conducted within as well as between groups. Despite extensive analyses, we identified only very limited effects. While some tests showed nominal significance, our results did not contain any clear identifiable patterns of effects that would be expected if a true underlying effect would be present. In conclusion, we do not find evidence for FA effects related to negative mood in fMRI, which questions the usefulness of FA measures for real-time fMRI neurofeedback as a treatment approach for affective disorders.

Effects of Rumination and Mindful Self-Focus Inductions During Daily Life in Patients With Remitted Depression: An Experimental Ambulatory Assessment Study.

Rumination has been proposed as an important risk factor for depression, whereas mindful attention is considered a protective form of self-focusing. Experimental studies have demonstrated differential effects of these modes when induced in the lab. However, their impact on daily life processes is poorly understood, particularly in individuals vulnerable to depressive relapses. The aim of our study was to examine short- and longer-term effects of repeated brief rumination and mindful self-focus inductions during daily life on momentary mood, cognitions, and cortisol in patients with remitted depression (rMDD) as well as in healthy individuals, and to identify their potential differential effects in these groups. The study involved repeated short ambulatory inductions of a ruminative or a mindful self-focus during daily life with additional assessments of momentary mood, rumination, self-acceptance, and cortisol over 4 consecutive days in a sample of patients with rMDD (n = 32, ≥2 lifetime episodes, age 19-55 years) and matched healthy controls (n = 32, age 21-54 years). Multilevel models revealed differential immediate effects of the two induction modes on all momentary mood and cognitive outcomes (all p's < .001), but not on cortisol. Detrimental effects of rumination over mindful self-focus inductions were particularly strong for cognitions in the patient group. Longer-term effects of the inductions over the day were lacking. This study underlines immediate deteriorating effects of an induced ruminative compared to a mindful self-focus on momentary mood and cognitions during daily life in patients with rMDD and in healthy individuals. The observed stronger rumination-related reactivity in patients suggests heightened cognitive vulnerability. Understanding rumination- and mindfulness-based mechanisms of action in real-life settings can help to establish mechanism-based treatment options for relapse prevention in depression.

Just a very expensive breathing training? Risk of respiratory artefacts in functional connectivity-based real-time fMRI neurofeedback.

Real-time functional magnetic resonance imaging neurofeedback (rtfMRI NFB) is a promising method for targeted regulation of pathological brain processes in mental disorders. But most NFB approaches so far have used relatively restricted regional activation as a target, which might not address the complexity of the underlying network changes. Aiming towards advancing novel treatment tools for disorders like schizophrenia, we developed a large-scale network functional connectivity-based rtfMRI NFB approach targeting dorsolateral prefrontal cortex and anterior cingulate cortex connectivity with the striatum. In a double-blind randomized yoke-controlled single-session feasibility study with N â€‹= â€‹38 healthy controls, we identified strong associations between our connectivity estimates and physiological parameters reflecting the rate and regularity of breathing. These undesired artefacts are especially detrimental in rtfMRI NFB, where the same data serves as an online feedback signal and offline analysis target. To evaluate ways to control for the identified respiratory artefacts, we compared model-based physiological nuisance regression and global signal regression (GSR) and found that GSR was the most effective method in our data. Our results strongly emphasize the need to control for physiological artefacts in connectivity-based rtfMRI NFB approaches and suggest that GSR might be a useful method for online data correction for respiratory artefacts.

Mindfulness-based focused attention training versus progressive muscle relaxation in remitted depressed patients: Effects on salivary cortisol and associations with subjective improvements in daily life.

Major Depression is a stress-related disorder characterized by altered hypothalamic-pituitary-adrenal axis function. Mindfulness-based interventions have shown to improve subjective parameters of stress and to reduce relapse rates in depressed patients. However, research on their effects on diurnal patterns of cortisol and associations with subjective outcomes is lacking. The present Ambulatory Assessment study investigated possible changes in daily rhythm cortisol parameters (cortisol awakening response (CAR), daily slope, total cortisol) in currently remitted individuals with recurrent depression who were randomized to a four-week mindfulness-based focused attention training (MBAT, n = 39) or a progressive muscle relaxation training (PMR, n = 39). A second aim was to investigate whether changes in cortisol were linked to improvements in affective and cognitive daily life states. On three weekdays before and after the intervention, seven saliva cortisol samples per day were collected. For analysis, multilevel models were applied. Results revealed no group-specific or general change in CAR and daily slopes from pre- to postintervention. In contrast, total cortisol increased across groups, which was however moderated by group and subjective improvement status. While cortisol increased irrespective of subjective improvement in PMR participants, MBAT participants with larger reductions in negative affect and rumination maintained their initial cortisol levels, whereas those with lower improvement paralleled the PMR group. Thereby, MBAT appeared to buffer an increase in overall cortisol secretion over time, but only in patients showing marked improvements in those affective and cognitive states that constitute core elements for depressive relapses in the vulnerability model of mindfulness-based cognitive therapy.

Induced ruminative and mindful attention in everyday life: an experimental ambulatory assessment study.

BACKGROUND AND OBJECTIVES: Rumination has been proposed as a risk factor for depression, while mindful attention might be protective. Differential effects of these attention foci have so far only been examined in the laboratory. Therefore, we conducted an experimental ambulatory assessment study using ruminative and mindful attention inductions in everyday life to examine their effects in a natural context. METHODS: Fifty young adults carried palmtops over three weekdays (rumination induction day, mindful attention induction day, noninduction day; randomized cross-over design). Ten times a day, participants rated ruminative self-focus and mood. On the induction days, they were additionally subjected to 3-min inductions of ruminative or mindful attention at each assessment. RESULTS: The two induction modes exhibited differential immediate effects on ruminative self-focus and mood. While induced rumination immediately deteriorated valence and calmness, induced mindful attention specifically enhanced calmness. Depressive symptoms did not moderate these effects. While overall longer term effects of the inductions were missing, the mindful attention day was associated with slightly increasing positive valence over the day. LIMITATIONS: The results need to be replicated in high-risk and patient samples to demonstrate the clinical significance of identified effects. CONCLUSIONS: Results confirm the emotional relevance of rumination and mindful attention in real world settings. Future work may test whether adaptive attention-focusing instructions delivered in daily life can support clinical interventions.