Reduced subgenual cingulate-dorsolateral prefrontal connectivity as an electrophysiological marker for depression.

Major Depressive Disorder (MDD) is a widespread mental illness that causes considerable suffering, and neuroimaging studies are trying to reduce this burden by developing biomarkers that can facilitate detection. Prior fMRI- and neurostimulation studies suggest that aberrant subgenual Anterior Cingulate (sgACC)-dorsolateral Prefrontal Cortex (DLPFC) functional connectivity is consistently present within MDD. Combining the need for reliable depression markers with the electroencephalogram's (EEG) high clinical utility, we investigated whether aberrant EEG sgACC-DLPFC functional connectivity could serve as a marker for depression.

Auricular transcutaneous vagus nerve stimulation modulates the heart-evoked potential.

Background: There is active interest in biomarker discovery for transcutaneous auricular vagus nerve stimulation (taVNS). However, greater understanding of the neurobiological mechanisms is needed to identify candidate markers. Accumulating evidence suggests that taVNS influences activity in solitary and parabrachial nuclei, the primary brainstem relays for the transmission of visceral sensory afferents to the insula.

Electrophysiological scarring in remitted depressed patients: Elevated EEG functional connectivity between the posterior cingulate cortex and the subgenual prefrontal cortex as a neural marker for rumination.

Introduction: Prior resting state fMRI studies have revealed that elevated connectivity between the default mode network (DMN) and subgenual prefrontal cortex (sgPFC) connectivity may underly maladaptive rumination, which is a major risk factor for depression. To further evaluate such relationship, we investigated whether posterior regions of the DMN, showed elevated connectivity with the sgPFC in remitted depressed patients (rMDD) and whether this connectivity was related to maladaptive rumination.

Methods: We examined whether rMDD (N = 20) had elevated EEG posterior DMN - sgPFC functional connectivity when compared to age and sex matched healthy controls (N = 17), and whether this posterior DMN - sgPFC connectivity positively correlated with rumination.