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The anticipation of control over aversive events in life is relevant for our mental health. Insights on the underlying neural mechanisms remain limited. We developed a new functional magnetic resonance imaging (fMRI) task that uses auditory stimuli to explore the neural correlates of (1) the anticipation of control over aversion and (2) the processing of aversion. In a sample of 25 healthy adults, we observed increased neural activation in the medial prefrontal cortex (ventromedial prefrontal cortex and rostral anterior cingulate cortex), other brain areas relevant for reward anticipation (ventral striatum, brainstem [ventral tegmental area], midcingulate cortex), and the posterior cingulate cortex when they anticipated control over aversion compared with anticipating no control (1). The processing of aversive sounds compared to neutral sounds (2) was associated with increased neural activation in the bilateral posterior insula. Our findings provide evidence for the important role of medial prefrontal regions in control anticipation and highlight the relevance of conceiving the neural mechanisms involved within a reward‐based framework. [ABSTRACT FROM AUTHOR]

Increased amygdala reactivity might lead to negative bias during emotional processing that can be reversed by antidepressant drug treatment. However, little is known on how N-methyl- d-aspartate (NMDA) receptor antagonism with ketamine as a novel antidepressant drug target might modulate amygdala reactivity to emotional stimulation. Using functional magnetic resonance imaging (fMRI) and resting-state fMRI (rsfMRI), we assessed amygdalo-hippocampal reactivity at baseline and during pharmacological stimulation with ketamine (intravenous bolus of 0.12 mg/kg, followed by a continuous infusion of 0.25 mg/kg/h) in 23 healthy subjects that were presented with stimuli from the International Affective Picture System (IAPS). We found that ketamine reduced neural reactivity in the bilateral amygdalo-hippocampal complex during emotional stimulation. Reduced amygdala reactivity to negative pictures was correlated to resting-state connectivity to the pregenual anterior cingulate cortex. Interestingly, subjects experienced intensity of psychedelic alterations of consciousness during ketamine infusion predicted the reduction in neural responsivity to negative but not to positive or neutral stimuli. Our findings suggest that the pharmacological modulation of glutamate-responsive cerebral circuits, which is associated with a shift in emotional bias and a reduction of amygdalo-hippocampal reactivity to emotional stimuli, represents an early biomechanism to restore parts of the disrupted neurobehavioral homeostasis in MDD patients. Hum Brain Mapp 37:1941-1952, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Patients with major depressive disorder (MDD) often show a tendency to strongly introspect and reflect upon their self, which has been described as increased self-focus. Although subcortical-cortical midline structures have been associated with reflection and introspection of oneself in healthy subjects, the neural correlates of the abnormally increased attribution of negative emotions to oneself, i.e. negative self-attribution, as hallmark of the increased self-focus in MDD remain unclear. The aim of the study was, therefore, to investigate the neural correlates during judgment of self-relatedness of positive and negative emotional stimuli thereby testing for emotional self-attribution. Using fMRI, we investigated 27 acute MDD patients and compared them with 25 healthy subjects employing a paradigm that focused on judgment of self-relatedness when compared with mere perception of the very same emotional stimuli. Behaviourally, patients with MDD showed significantly higher degrees of self-relatedness of specifically negative emotional stimuli when compared with healthy subjects. Neurally, patients with MDD showed significantly lower signal intensities in various subcortical and cortical midline regions like the dorsomedial prefrontal cortex (DMPFC), supragenual anterior cingulate cortex, precuneus, ventral striatum (VS), and the dorsomedial thalamus (DMT). Signal changes in the DMPFC correlated with depression severity and hopelessness whereas those in the VS and the DMT were related to judgment of self-relatedness of negative emotional stimuli. In conclusion, we present first evidence that the abnormally increased negative self-attribution as hallmark of the increased self-focus in MDD might be mediated by altered neural activity in subcortical-cortical midline structures. Hum Brain Mapp, 2009. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Damasio proposes in his somatic marker theory that not only cognitive but also affective components are critical for decision making. Since affective judgment requires an interplay between affective and cognitive components, it might be considered a key process in decision making that has been linked to neural activity in ventromedial prefrontal cortex (VMPFC). Using functional magnetic resonance imaging (fMRI), we examined the relationship between VMPFC, emotionally (unexpected)- and cognitively (expected)-accentuated affective judgment, and beneficial decision making (Iowa Gambling Task; IGT) in healthy subjects. Neuronal activity in the VMPFC during unexpected affective judgment significantly correlated with both global and final performance in the IGT task. These findings suggest that the degree to which subjects recruit the VMPFC during affective judgment is related to beneficial performance in decision making in gambling. Hum Brain Mapp 2006. © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]