Does rTMS on brain areas of mirror neurons lead to higher improvements on symptom severity and empathy compared to the rTMS standard procedure? - Results from a double-blind interventional study in individuals with major depressive disorders

More rTMS pulses or more sessions? The impact on treatment outcome for treatment resistant depression

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is effective for treatment-resistant depression (TRD). Optimal rTMS parameters remain unclear, especially whether number of sessions or amount of pulses contribute more to treatment outcome. We hypothesize that treatment outcome depends on the number of sessions rather than on the amount of pulses.

METHODS

We searched databases for randomized clinical trials (RCTs) on high-frequent (HF) or low-frequent (LF)-rTMS targeting the left or right DLPFC for TRD. Treatment efficacy was measured using standardized mean difference (SMD), calculated from pre- and post-treatment depression scores. Meta-regressions were used to explore linear associations between SMD and rTMS pulses, pulses/session and sessions for HF and LF-rTMS, separately for active and sham-rTMS. If these variables showed no linear association with SMD, we divided the data into quartiles and explored subgroup SMDs.

RESULTS

Eighty-seven RCTs were included: 67 studied HF-rTMS, eleven studied LF-rTMS, and nine studied both. No linear association was found between SMD and amount of pulses or pulses/session for HF and LF-rTMS. Subgroup analyses showed the largest SMDs for 1200-1500 HF-pulses/session and 360-450 LF-pulses/session. The number of sessions was significantly associated with SMD for active HF (β = 0.09, p < 0.05) and LF-rTMS (β = 0.06, p < 0.01). Thirty was the maximal number of sessions, in the included RCTs.

CONCLUSION

More rTMS sessions, but not more pulses, were associated with improved treatment outcome, in both HF and LF-rTMS. Our findings suggest that 1200-1500 HF-pulses/session and 360-450 LF-pulses/session are already sufficient, and that a treatment course should consist of least 30 sessions for higher chance of response.

Functional connectivity of the left inferior parietal lobule mediates the impact of anxiety and depression symptoms on sleep quality in healthy adults

Individuals with anxiety and depression symptoms are vulnerable to sleep disturbances. The current study aimed to explore the shared neuro-mechanisms underlying the effect of anxiety and depression symptoms on sleep quality. We recruited a cohort of 92 healthy adults who underwent functional magnetic resonance imaging scanning. We measured anxiety and depression symptoms using the Zung Self-rating Anxiety/Depression Scales and sleep quality using the Pittsburgh Sleep Quality Index. Independent component analysis was used to explore the functional connectivity (FC) of brain networks. Whole-brain linear regression analysis showed that poor sleep quality was associated with increased FC in the left inferior parietal lobule (IPL) within the anterior default mode network. Next, we extracted the covariance of anxiety and depression symptoms using principal component analysis to represent participants' emotional features. Mediation analysis revealed that the intra-network FC of the left IPL mediated the association between the covariance of anxiety and depression symptoms and sleep quality. To conclude, the FC of the left IPL may be a potential neural substrate in the association between the covariance of anxiety and depression symptoms and poor sleep quality, and may serve as a potential intervention target for the treatment of sleep disturbance in the future.

Predominant polarity as a neurobiological specifier in bipolar disorder: Evidence from a multimodal neuroimaging study

BACKGROUND

While predominant (PP) and onset polarity (OP) have considerable clinical and treatment implications in bipolar disorder (BD), the neurobiological underpinnings of PP and OP from a radiological perspective remain largely unknown. The main objective of this study is to investigate the neuroanatomical profile of polarity subphenotypes (PP and OP) in euthymic BD patients, using a standardized multimodal neuroimaging protocol to evaluate regional gray matter (GM) volumes, cortical thickness, as well as white matter (WM) integrity of major projection, commissural and association tracts.

METHODS

Forty-two euthymic BD patients stratified for PP and OP and 42 healthy controls (HC) were included in this computational neuroimaging study to comprehensively characterize gray and white matter alterations. Univariate analyses of covariance (ANCOVAs) were conducted with Bonferroni corrections for each MRI modality and Cohen's d effect sizes were calculated for group comparisons.

RESULTS

Phenotype-associated cortical thickness abnormalities and volumetric alterations were identified, but no WM changes ascertained. Specifically, we found a main effect of OP on GM volume of left middle frontal gyrus and of OP and PP (either or both) on cortical thickness of various regions previously implicated in BD, i.e. inferior frontal gyrus-pars opercularis (left) and pars orbitalis (bilateral), left lateral orbitofrontal gyrus, bilateral medial segment of the superior frontal gyrus, left planum polare, right anterior cingulate gyrus, left anterior and posterior insula, bilateral frontal operculum (both OP and PP); left anterior and posterior orbitofrontal gyrus, left transverse temporal gyrus, right posterior insula (only OP); and right medial frontal cortex (only PP). Based on the magnitude of differences on pairwise comparisons, we found a large effect of OP on cortical thickness in a single region (left anterior orbitofrontal gyrus) (OP-M > OP-D), while PP subgroups showed large or medium effect size differences in cortical thickness (PP-M > PP-D) in a wider array of regions (right medial frontal cortex, left frontal operculum, left inferior frontal gyrus-pars opercularis, bilateral medial segment of the superior frontal gyrus). For most regions, PP-D patients showed the greatest decreases in cortical thickness compared to HC while PP-M showed the smallest, with PP-U showing an "unspecified" pattern mostly lying in-between PP-D and PP-M.

CONCLUSIONS

Our multimodal imaging findings suggest specific polarity BD subgroups with compromised cortical thickness; we recorded a greater impact of PP on brain structure compared to OP, which provides additional evidence that PP can be considered as a neurobiological specifier in BD.

Contagious Depression: Automatic Mimicry and the Mirror Neuron System - A Review

Contagious depression is a theory proposing that depression can be induced or triggered by our social environment. This theory is based on emotional contagion, the idea that affective states can be transferred during social interaction, since humans can use emotional contagion to communicate feelings and emotions in conscious and unconscious ways. This review presents behavioral, physiological, and neuroanatomical aspects of two essential contagious depression mechanisms, automatic mimicry and the mirror neuron system.

Self-Reported Emotion Regulation Is Associated With Response to Test of Cardiac Vagal Function

Abstract. Parasympathetic function and emotional self-regulation (ESR) share neuroanatomic structures. Based on Porges’ Polyvagal Theory and the Neurovisceral Integration Model (NIM), we compared vagally mediated heart-rate variability (vmHRV) with psychometrically assessed ESR. We hypothesized that vmHRV and ESR would be associated during rest, a vagal function test, and recovery from that test. A significant association would justify the psychometric measuring of parasympathetic health, which is less burdensome than its psychophysiological assessment. Two hundred thirteen healthy males (aged: 18–26 years, M = 20.29 years) took part in the present study. They completed the Emotion Regulation Questionnaire (ERQ) and underwent the Cold Face Test (CFT) for 4 min wearing ambulatory electrocardiograms. A High frequency (HF) band was used as a measure of vmHRV before, during, and after the CFT. Associations between the HF band and ESR were analyzed with partial rank correlations. There was no significant association between ERQ scores and the response to the CFT itself. But there was an almost significant association between the ERQ scale Cognitive Appraisal and baseline vmHRV, and a significant association between Cognitive Appraisal and cardiac recovery from the CFT, that is, participants with higher scores on that ESR scale revealed a tendency to exhibit greater vmHRV during baseline and they exhibited greater vagal withdrawal during recovery from the CFT. Cognitive appraisal as a psychometrically assessed emotion regulatory process was reflected in a more flexible parasympathetic activity (i.e., better cardiac vagal health) during recovery from an exclusively physiological stressor. This lends convergent validity to self-reported emotion regulation, and justification for its use as a measure of ESR as a trait, offering further support for the Polyvagal Theory and NIM.

Selective Serotonin Reuptake Inhibitor-Induced Sexual Dysfunction: Current Management Perspectives

Any type of sexual dysfunction is an important problem in half of the patients with depressive disorder. On the other hand, one to a quarter of people without any depressive disorder experience sexual dysfunction. Antidepressant agents can lead to all types of sexual side effects including arousal, libido, orgasm and ejaculation problems. Selective serotonin reuptake inhibitors (SSRIs) are a widely used class of drugs which are prescribed for the treatment of a variety of disorders, including major depressive disorder, obsessive-compulsive disorder, posttraumatic stress disorder, panic disorder, generalized anxiety disorder, and impulse control disorders. It has been reported that one in eight people have utilized one of the SSRIs in the past 10 years. Some studies reported up to 80% of SSRI-induced sexual side effects. Management of SSRI-induced sexual dysfunction seems to be complex and hard. In this paper, SSRI-induced sexual dysfunction and new perspectives in the management of this problem were reviewed.

Systematic Review of Meta-Analyses: Exercise Effects on Depression in Children and Adolescents

BACKGROUND

Depression is a common threat to children and adolescents in terms of affecting psychosocial development and increasing their risk of suicide. Apart from conventional treatments for depression, physical exercise has become a promising alternative. This paper aims to systematically review the existing meta-analyses that focus on the impact of physical exercise on clinical and nonclinical depression in children and adolescents.

METHODS

A systematic literature search was conducted using PsycINFO, PsycARTICLES, MedLine, PubMed, and hand searching. Risk of bias analysis, effect sizes calculations, and evaluation of the methodological characteristics (AMSTAR 2) were carried out.

RESULTS

Four meta-analyses met the inclusion criteria. After analysing the overlap, the total sample contained 30 single studies (mostly including gender mixed samples) and 2,110 participants (age range 5-20 years). The medium duration of the interventions was 11.5 weeks. The sessions had a medium length of 41 min, and the frequency of implementation was three sessions per week. The most implemented intervention type was aerobic exercise, while control groups mainly continued with their regular routine, among other related options. The overall mean effect of physical exercise on depression was medium (d = -0.50). The additional analysis in clinically depressed samples documented a small to medium mean effect (d = -0.48) in favor of the intervention.

CONCLUSION

The small to medium but consistently positive effects that were found in the present study place physical exercise as a promising and helpful alternative for children and adolescents with clinical and nonclinical depression. The limited literature focused on children and adolescents in comparison with adult samples points to the need for further research.