Trait-related changes in brain network topology in premenstrual dysphoric disorder.

The female predominance in the prevalence of depression is partially accounted by reactivity to hormonal fluctuations. Premenstrual dysphoric disorder (PMDD) is a reproductive subtype of depression characterized by cyclic emotional and somatic symptoms that recur before menstruation. Despite the growing understanding that most psychiatric disorders arise from dysfunctions in distributed brain circuits, the brain's functional connectome and its network properties of segregation and integration were not investigated in PMDD. To this end, we examined the brain's functional network organization in PMDD using graph theoretical analysis. 24 drug naïve women with PMDD and 27 controls without premenstrual symptoms underwent 2 resting-state fMRI scans, during the mid-follicular and late-luteal menstrual cycle phases. Functional connectivity MRI, graph theory metrics, and levels of sex hormones were computed during each menstrual phase. Altered network topology was found in PMDD across symptomatic and remitted stages in major graph metrics (characteristic path length, clustering coefficient, transitivity, local and global efficiency, centrality), indicating decreased functional network segregation and increased functional network integration. In addition, PMDD patients exhibited hypoconnectivity of the anterior temporal lobe and hyperconnectivity of the basal ganglia and thalamus, across menstrual phases. Furthermore, the relationship between difficulties in emotion regulation and PMDD was mediated by specific patterns of functional connectivity, including connections of the striatum, thalamus, and prefrontal cortex. The shifts in the functional connectome and its topology in PMDD may suggest trait vulnerability markers of the disorder.

Neuroimaging premenstrual dysphoric disorder: A systematic and critical review.

Endocrine organizational and activational influences on cognitive and affective circuits are likely critical to the development of premenstrual dysphoric disorder (PMDD), a sex-specific hormone-dependent mood disorder. An overview of the anatomical and functional neural characterization of this disorder is presented here by means of neuroimaging correlates, identified from eighteen publications (n = 361 subjects). While white matter integrity remains uninvestigated, greater cerebellar grey matter volume and metabolism were observed in patients with PMDD, along with altered serotonergic and GABAergic neurotransmission. Differential corticolimbic activation in response to emotional stimuli distinguishes the PMDD brain, namely enhanced amygdalar and diminished fronto-cortical function. Thus far, the emotional distress and dysregulation linked to PMDD seem to be defined by structural, chemical and functional brain signatures; however, their characterization remains sparsely studied and somewhat inconsistent. Clear and well-replicated neurobiological features of PMDD are needed to promote timely diagnoses and inform development of prevention and treatment strategies.

The Role of Interference and Inhibition Processes in Dysphoric Early Adolescents.

Cognitive theories emphasize the importance of attentional biases in the development and maintenance of depression. Noteworthy, recent studies indicate that depression-related biases only occur in later stages of attentional processing. This is consistent with the idea that attention is a multicomponent process, consisting of at least two mechanisms: selection and inhibition. Therefore, this study aims to investigate interference and inhibition toward angry and happy stimuli in dysphoric adolescents compared to nondysphoric adolescents. To examine interference and inhibition of emotional information in 21 dysphoric (17 girls) and 28 nondysphoric adolescents (17 girls), 10-16 years of age, a Negative Affective Priming task was used. In this task, a target has to be evaluated as positive or negative while ignoring a distractor. As expected, dysphoric adolescents showed both higher interference from and higher inhibition of angry stimuli relative to nondysphoric adolescents. In contrast, happy stimuli did not lead to interference and consequently did not have to be inhibited in either group. Finally, a positive relation was found between interference and the subsequent inhibition of emotional stimuli. These observations confirm the existence of a bias toward angry faces in dysphoric adolescents and indicate a higher inhibition of angry faces in dysphoric adolescents compared to nondysphoric adolescents. The obtained results are different from those of similar previous studies in depressed or dysphoric adults using sad faces or negatively valenced words and might reveal important emotion-specific or age-specific inhibitory biases.

Epidemiological Distribution and Subtype Analysis of Premenstrual Dysphoric Disorder Syndromes and Symptoms Based on TCM Theories.

We performed an epidemiological investigation of subjects with premenstrual dysphoric disorder (PMDD) to identify the clinical distribution of the major syndromes and symptoms. The pathogenesis of PMDD mainly involves the dysfunction of liver conveyance and dispersion. Excessive liver conveyance and dispersion are associated with liver-qi invasion syndrome, while insufficient liver conveyance and dispersion are expressed as liver-qi depression syndrome. Additionally, a nonconditional logistic regression was performed to analyze the symptomatic features of liver-qi invasion and liver-qi depression. As a result of this analysis, two subtypes of PMDD are proposed, namely, excessive liver conveyance and dispersion (liver-qi invasion syndrome) and insufficient liver conveyance and dispersion (liver-qi depression syndrome). Our findings provide an epidemiological foundation for the clinical diagnosis and treatment of PMDD based on the identification of different types.

Alterations of GABA and glutamate-glutamine levels in premenstrual dysphoric disorder: a 3T proton magnetic resonance spectroscopy study.

Increasing evidence has suggested that the GABAergic neurotransmitter system is involved in the pathogenesis of premenstrual dysphoric disorder (PMDD). We used proton magnetic resonance spectroscopy ((1)H MRS) to investigate whether PMDD is associated with alterations in brain GABA levels. Levels of glutamate-glutamine (Glx) were also explored. Participants comprised 22 women with PMDD and 22 age-matched healthy controls who underwent 3T (1)H MRS during the late luteal phase of the menstrual cycle. GABA+ and Glx levels were quantified in the anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC) and the left basal ganglia (ltBG). Water-scaled GABA+ concentrations and GABA+/tCr ratios were significantly lower in both the ACC/mPFC and ltBG regions of PMDD women than in healthy controls. Glx/tCr ratios were significantly higher in the ACC/mPFC region of PMDD women than healthy controls. Our preliminary findings provide the first report of abnormal levels of GABA+ and Glx in mood-related brain regions of women with PMDD, indicating that dysregulation of the amino acid neurotransmitter system may be an important neurobiological mechanism in the pathogenesis of PMDD.