Magnetic Resonance Imaging Studies of Postpartum Depression: An Overview

Abstract

Postpartum depression is a frequent and disabling condition whose pathophysiology is still unclear. In recent years, the study of the neural correlates of mental disorders has been increasingly approached using magnetic resonance techniques. In this review we synthesize the results from studies on postpartum depression in the context of structural, functional, and spectroscopic magnetic resonance studies of major depression as a whole. Compared to the relative wealth of data available for major depression, magnetic resonance studies of postpartum depression are limited in number and design. A systematic literature search yielded only eleven studies conducted on about one hundred mothers with postpartum depression overall. Brain magnetic resonance findings in postpartum depression appear to replicate those obtained in major depression, with minor deviations that are not sufficient to delineate a distinct neurobiological profile for this condition, due to the small samples used and the lack of direct comparisons with subjects with major depression. However, it seems reasonable to expect that studies conducted in larger populations, and using a larger variety of brain magnetic resonance techniques than has been done so far, might allow for the identification of neuroimaging signatures for postpartum depression.

Amygdala and affective responses to infant pictures: Comparing depressed and non‐depressed mothers and non‐mothers

“…PPD and MDD, assessed independently, show an amygdalar hypo‐responsiveness and hyper‐responsiveness, respectively, to negative stimuli. In addition, it is difficult to compare and interpret the neuroimaging literature on the neural responsiveness to infant stimuli as a result of the wide variability in methodologies such as stimulus modality (auditory, visual), standardisation of the stimuli, sample size, analysis methods and the postpartum stage of mothers …”

“…What we do know about the neural underpinning of the condition/disorder is a result of a few recent functional magnetic resonance imaging (fMRI) studies. 17,42 These studies have identified an inverse relationship between amygdala responsiveness to negative stimuli (including infant faces in distress) and symptom severity in PPD. 43,44 Thus, in comparison to non-depressed mothers, depressed mothers show reduced amygdalar responses to negative infant-related stimuli.…”

“…However, the neural mechanisms underlying PPD are not well understood. What we do know about the neural underpinning of the condition/disorder is a result of a few recent functional magnetic resonance imaging (fMRI) studies . These studies have identified an inverse relationship between amygdala responsiveness to negative stimuli (including infant faces in distress) and symptom severity in PPD .…”

Resting-State BOLD MRI for Perfusion and Ischemia

“…The temporal coherence of the BOLD signal is then compared to the timing of the task to extract the location of voxels that are active during the performance of the task. fMRI has been used extensively to study motor, sensory, and language activation and is clinically used as a complementary imaging technique in neuropsychiatric and neurodegenerative diseases such as schizophrenia [34], attention deficit and hyperactivity syndrome [35], and depression [36]. It may also be used to determine hemispheric language dominance in the pre-operative setting (e.g., before temporal lobectomy or hemispherectomy in patients with medically refractory epilepsy) or for surgical planning in the setting of brain masses [37].…”

Emotional Rejection of the Infant: Status of the Concept

“…Some authors have emphasized the role of oxytocin [148,150]. In the last 5 years, neuroscientists have begun to examine differences in ‘the parental brain' when the mother is depressed [147,149,151,152,153,154,155], but there has so far been no attempt to study rejecting mothers. …”