Features Of Major Depressive Disorder Research Articles

Neurocognitive Characteristics of Major Depressive Disorder Measured by Degraded Continuous Performance Test

Neurocognitive Characteristics of Major Depressive Disorder Measured by Degraded Continuous Performance Test

Cognitive dysfunction: An important feature of major depressive disorder

Depression is a common mental illness with high prevalence, disability, and suicide rates. Most patients experience recurrent attacks, which converts depression into a chronic disease. Major depressive disorder (MDD) is a type of emotional dysfunction caused by genetic abnormalities or great changes in the patient’s environment, which can manifest as a host of symptoms such as persistent and spontaneous depression with changes in cognitive function. According to worldwide statistics, 50% of suicides each year occur during episodes of depression, and patients with MDD are 20 times more likely to commit suicide than the general population.

Altered beta band spatial-temporal interactions during negative emotional processing in major depressive disorder: An MEG study

BackgroundThe mood-concordance bias is a key feature of major depressive disorder (MDD), but the spatiotemporal neural activity associated with emotional processing in MDD remains unclear. Understanding the dysregulated connectivity patterns during emotional processing and their relationship with clinical symptoms could provide insights into MDD neuropathology. MethodsWe enrolled 108 MDD patients and 64 healthy controls (HCs) who performed an emotion recognition task during magnetoencephalography recording. Network-based statistics (NBS) was used to analyze whole-brain functional connectivity (FC) across different frequency ranges during distinct temporal periods. The relationship between the aberrant FC and affective symptoms was explored. ResultsMDD patients exhibited decreased FC strength in the beta band (13–30 Hz) compared to HCs. During the early stage of emotional processing (0-100 ms), reduced FC was observed between the left parahippocampal gyrus and the left cuneus. In the late stage (250-400 ms), aberrant FC was primarily found in the cortex-limbic-striatum systems. Moreover, the FC strength between the right fusiform gyrus and left thalamus, and between the left calcarine fissure and left inferior temporal gyrus were negatively associated with Hamilton Depression Rating Scale (HAMD) scores. LimitationsMedication information was not involved. ConclusionMDD patients exhibited abnormal temporal-spatial neural interactions in the beta band, ranging from early sensory to later cognitive processing stages. These aberrant interactions involve the cortex-limbic-striatum circuit. Notably, aberrant FC in may serve as a potential biomarker for assessing depression severity.

Association between thyroid autoimmunity and clinical characteristics in first-episode and drug-naive depressed patients with suicide attempts

BackgroundPrevious reports had linked depression to thyroid function. However, the relationship between thyroid function and clinical characteristics in major depressive disorder (MDD) patients with suicidal attempts (SA) is still unclear. AimsThis study aims to reveal the association between thyroid autoimmunity and clinical characteristics in depressed patients with SA. MethodsWe divided 1718 first-episode and drug-naive MDD patients into groups with suicide attempt (MDD-SA) and without suicide attempt (MDD-NSA). Hamilton Depression Rating Scale (HAMD), Hamilton Anxiety Rating Scale (HAMA), and the positive subscale of the Positive and Negative Syndrome Scale (PANSS) were assessed; thyroid function and autoantibodies were detected. ResultsThe total scores of HAMD, HAMA and psychotic positive symptoms were significantly higher in patients with MDD-SA, accompanied by higher levels of TSH, TG-Ab and TPO-Ab, than in patients with MDD-NSA, without gender differences. Total scores of positive symptoms (TSPS) in MDD-SA patients with increased TSH or TG-Ab was significantly higher than in MDD-NSA patients and in MDD-SA patients with normal TSH and TG-Ab. The proportion of elevated-TSPS in MDD-SA patients was >4 times that in MDD-NSA patients. The proportion of MDD-SA patients with elevated-TSPS was >3 times that with not-elevated TSPS patients. ConclusionsThyroid autoimmune abnormalities and psychotic positive symptoms may be the clinical features of MDD-SA patients. Psychiatrists should be more alert to the possibility of suicidal behaviors when they first encounter such a patient.

Neuropsychiatric and cognitive features of major depressive disorder in aging, based on the data from the US National Alzheimer's Coordinating Center (NACC)

ObjectiveThe diagnosis of Major Depressive Disorder (MDD) is based on the DSM-V criteria and is established by a clinician. This allows quantifying depression based on clinical criteria. As such, MDD differs from other types of depressions that are measured by subjective scales. Here, we evaluated the MDD risk factor on other neuropsychiatric symptoms (NPS) as well as MDD association with cognitive performance in Alzheimer's disease (AD), Mild Cognitive Impairment (MCI) and Healthy Controls (HC). MethodsData of 208 patients with AD, 291 patients with MCI and 647 HC were extracted from the National Alzheimer's Coordinating Center database. All participants included in this study were assessed by a physician for the MDD criteria, underwent an NPS evaluation using the NeuroPsychiatric Inventory, and a comprehensive cognitive assessment. Participants were classified as being with and without MDD. We performed logistic regression and MANCOVA models respectively with NPS and cognitive performance as variables of interest and MDD as fixed factors within each group. The MANCOVA was controlled for the effects of age, sex, and education. ResultsMDD increased the risk for psychotic, affective and behavioral NPS in MCI, as well as affective and behavioral NPS in HC and AD. Also, MCI with MDD had lower performance on selective attention and mental flexibility. ConclusionsMDD seems to increase the probability of a prevalence of NPS in all groups (HC, MCI and AD). Longitudinal data processing would help to understand the neuropsychiatric evolution of elderly subjects with MDD.

Associations between Antidepressant Resistance, Risks of Previous Pain Disorders, and Risks of Diagnostic Conversion to Bipolar Disorder among Adolescent and Young Adult Patients with Major Depressive Disorder

Background: Increasing studies have supported the relationship between pain disorders and treatment-resistant depression (TRD) or chronic pain disorders may possibly impact the clinical characteristics of major depressive disorder (MDD). Thus, this linkage has been seen as a potential clinical marker to predict diagnostic conversion to bipolar disorder (BD) among patients with MDD. Methods: With the Taiwan National Health Insurance Research Database, we enrolled 4,760 adolescent and young adult patients with TRD, 19,040 counterparts with antidepressant-responsive depression, and 19,040 age-/sex-/residence-/family income-matched controls. Then, we followed up on their conversion from MDD to BD from enrollment to the end of 2011. Results: The incidence of diagnostic progression from MDD to BD was significantly higher in the TRD group than the non-TRD group (30.5% versus 10.6%, p < 0.001). Logistic regression analysis with adjustment of demographic characteristics showed that the TRD group had the highest risks of previous migraine, tension headache, fibromyalgia, peripheral neuropathy, dysmenorrhea, and irritable bowel syndrome, followed by the non-TRD group, and then the control group (p < 0.05). In further analysis of those data stratified by diagnostic progression to BD, we found no consistent results among different subgroups. Conclusion: Clinicians should be aware of the higher risk of developing TRD in depressive patients with comorbid pain disorders such as migraine, tension headache, fibromyalgia, peripheral neuropathy, dysmenorrhea, and irritable bowel syndrome. Besides, we found no consistent results in predicting diagnostic conversion from MDD to BD when the rôle of these pain disorders was evaluated.

Objective and Subjective Sleep Measures Are Related to Suicidal Ideation and Are Transdiagnostic Features of Major Depressive Disorder and Social Anxiety Disorder

Suicide is a major public health problem and previous studies in major depression and anxiety show problematic sleep is a risk factor for suicidal ideation (SI). However, less is known about sleep and SI in social anxiety disorder (SAD), despite the pervasiveness of SAD. Therefore, the current study comprised participants with major depressive disorder (MDD) (without comorbid SAD) (n = 26) and participants with SAD (without comorbid MDD) (n = 41). Wrist actigraphy was used to estimate sleep duration, wake after sleep onset, and sleep efficiency; sleep quality was evaluated with self-report. Self-report was also used to examine SI. These measures were submitted to independent t-tests and multiple regression analysis. t-test results revealed sleep and SI did not differ between MDD and SAD groups. Multiple regression results showed shorter sleep duration and worse sleep quality related to greater SI when taking symptom severity and age into account. Post-hoc partial correlational analysis showed these sleep-SI relationships remained significant after controlling for symptom severity and age. Preliminary findings indicate sleep and SI may be transdiagnostic features of MDD and SAD. Evidence of distinct sleep-SI relationships are consistent with previous reports showing that sleep difficulties contribute to SI. Altogether, improving sleep duration and sleep quality may reduce the risk of SI.

Lumateperone treatment for major depressive episodes with mixed features in major depressive disorder and bipolar I or bipolar II disorder

Lumateperone treatment for major depressive episodes with mixed features in major depressive disorder and bipolar I or bipolar II disorder

Functional MRI study of feedback-based reinforcement learning in depression.

Reinforcement learning depends upon the integrity of emotional circuitry to establish associations between environmental cues, decisions, and positive or negative outcomes in order to guide behavior through experience. The emotional dysregulation characteristic of major depressive disorder (MDD) may alter activity in frontal and limbic structures that are key to learning. Although reward and decision-making have been examined in MDD, the effects of depression on associative learning is less well studied. We investigated whether depressive symptoms would be related to abnormalities in learning-related brain activity as measured by functional magnetic resonance imaging (fMRI). Also, we explored whether melancholic and atypical features were associated with altered brain activity. We conducted MRI scans on a 4T Varian MRI system in 10 individuals with MDD and 10 healthy subjects. We examined event-related brain activation during feedback-based learning task using Analysis of Functional NeuroImages (AFNI) for image processing and statistical analysis. We observed that MDD patients exhibited reduced activation in visual cortex but increased activation in cingulate and insular regions compared to healthy participants. Also, in relation to features of depressive subtypes, we observed that levels of activation in striatal, thalamic, and precuneus regions were negatively correlated with atypical characteristics. These results suggest that the effects of MDD change the neural circuitry underlying associative learning, and these effects may depend upon subtype features of MDD.

A transdiagnostic evaluation of contrast avoidance across generalized anxiety disorder, major depressive disorder, and social anxiety disorder

BackgroundThe contrast avoidance model (CAM) proposes that persons with generalized anxiety disorder (GAD) are sensitive to sharp increases in negative emotion or decreases in positive emotion (i.e., negative emotional contrasts; NEC) and use worry to avoid NEC. Sensitivity to and avoidance of NEC could also be a shared feature of major depressive disorder (MDD) and social anxiety disorder (SAD). MethodsIn a large college sample (N = 1409), we used receiver operating characteristics analysis to examine the accuracy of a measure of emotional contrast avoidance in detecting probable GAD, MDD, and SAD. ResultsParticipants with probable GAD, MDD, and SAD all reported higher levels of contrast avoidance than participants without the disorder (Cohen’s d = 1.32, 1.62 and 1.53, respectively). Area under the curve, a measure of predictive accuracy, was .81, .87, and .83 for predicting probable GAD, MDD, and SAD, respectively. A cutoff score of 48.5 optimized predictive accuracy for probable GAD and SAD, and 50.5 optimized accuracy for probable MDD. ConclusionA measure of emotional contrast avoidance demonstrated excellent ability to predict probable GAD, MDD, and SAD. Sensitivity to and avoidance of NEC appears to be a transdiagnostic feature of these disorders.

Anhedonia in epilepsy

BackgroundAnhedonia, the impaired ability to experience pleasure, is a core feature of major depressive disorder, one of the most common comorbidities in epilepsy. It is also reported as a clinical feature independent of depression in a number of other neurological conditions. This study aimed to establish the prevalence of anhedonia in a sample of people with epilepsy, with and without a diagnosis of depression, and to examine the clinical and demographic characteristics of those who present with this symptom. MethodsA consecutive sample of 211 people (118 female, 93 male, mean age 38.09 years) completed the Snaith-Hamilton Pleasure Scale (SHAPS) to determine the presence of anhedonia and the Hospital Anxiety and Depression Scale to determine levels of anxiety and depression. The majority of patients had focal epilepsy (n = 165), and the remaining patients had generalized epilepsy (n = 22), or unclassified epilepsy (n = 24). Sixteen percent of the sample had a clinical diagnosis of depression at the time of the study. ResultsOver one in three of the sample (35%) reported significant anhedonia on the SHAPS. While these patients were more likely to have a diagnosis of depression (p < 0.01), 30% of people without a diagnosis of depression also reported significant anhedonia. Difficulties gaining pleasure on 12 of the 14 items on the SHAPS were associated with cognitive difficulties, with those reporting an inability to feel pleasure on the item scoring significantly lower on tests of cognitive function than those who were able to gain pleasure. Of the three cognitive domains examined (overall intellectual ability, verbal memory, and processing speed), a poor memory had the strongest relationship; with lower memory function associated with an impaired ability to experience pleasure on 9 of the 14 items. ConclusionWhile anhedonia is well recognized as a feature of depression, our data suggests that it can be present in up to a third of people with epilepsy who do not have a diagnosis of depression. Cognitive difficulties, particularly impaired memory function may mediate some features of anhedonia. The implications of these findings for the clinical management of anhedonia in people with epilepsy are discussed.

Gender differences in major depressive disorders: A resting state fMRI study.

Major depressive disorder (MDD) has a high disability rate and brings a large disease burden to patients and the country. Significant sex differences exist in both the epidemiological and clinical features in MDD. The effect of sex on brain function in MDD is not clear now. Regional homogeneity (ReHo) and ALFF are widely used research method in the study of brain function. This research aimed to use ReHo and ALFF to explore gender differences in brain function images in MDD. Eighty first-episode drug-naive patients (47 women and 30 men) with MDD and 85 age, education matched healthy volunteers (47 women and 31 men) were recruited in our study and participated in resting-state functional magnetic resonance imaging scans. ReHo and ALFF were used to assess brain activity, two-way ANOVA and post hoc analysis was conducted to explore the sex difference in MDD. Correlation analysis was used to explore the relationship between abnormal brain functioning and clinical symptoms. We observed sex-specific patterns and diagnostic differences in MDD Patients, further post hoc comparisons indicated that women with MDD showed decreased ALFF value in the right superior occipital gyrus and decreased ReHo value in the left calcarine and left dorsolateral superior frontal gyrus compared with HC females and men with MDD. Men with MDD showed decreased ReHo value in the right median cingulate gyrus compared with HC males and increased ReHo value in the left dorsolateral superior frontal gyrus compared with HC males, we also found that HC males showed higher ReHo value in the right median cingulate gyrus than HC females. Men and women do have sex differences in brain function, the occipital lobe, calcarine, DLPFC, and DCG were the main different brain regions found between male and female in MDD, which may be the biomarker brain regions that can help diagnose and treat MDD in men and women.

Memory and processing speed impairments in first-episode drug-naïve patients with major depressive disorder

BackgroundCognitive impairment, an intrinsic feature of major depressive disorder (MDD), affects daily and social functioning in depression patients. However, the cognitive impairment profile in MDD remains ambiguous because of the high heterogeneity of previous studies. MethodsFour cognitive domains, including memory, processing speed, executive function (EF), and attention, were assessed in 184 first-episode drug-naïve (FEDN) MDD patients and matched 71 healthy controls (HCs). The effects of demographic and depressive factors on cognitive performance were analyzed using various statistical methods, including multi-factor analysis of variance, Mann-Whitney U test, and Spearman's rank correlation. In addition, the impact of depression severity on cognitive function was further assessed using subgroup analyses and partial correlation analyses. ResultsAge and education significantly impacted most cognitive performances, and depression severity appeared to influence processing speed. Moreover, cognitive scores in memory and processing speed, rather than in EF and attention, were significantly different between FEDN MDD patients and HCs after controlling for sex, age, educational attainment, household income, and body mass index. LimitationsThe number of HCs was relatively small, which may have slightly reduced the study's statistical power. ConclusionsAge and educational attainment have confirmative confounding effects greater than those of depression in most cognitive functions. More importantly, memory and processing speed were impaired in MDD after strictly controlling for confounders. These findings provide new information for understanding the pattern of cognitive impairment and offer clues for further exploring the pathogenesis of cognitive abnormalities in MDD.

Aberrant interhemispheric functional connectivity in major depressive disorder with and without anhedonia

ObjectiveAnhedonia is a core feature of major depressive disorder (MDD), and as a subtype of depression, MDD with anhedonia may have exceptional neurobiological mechanisms. However, the neuropathology of anhedonia in MDD remains unclear. Thus, this study aimed to investigate the brain functional differences between MDD with and without anhedonia.MethodsA total of 62 individuals including 22 MDD patients with anhedonia, 20 MDD patients without anhedonia, and 20 healthy controls (HCs) were recruited for this study. All participants underwent 3.0-T functional magnetic resonance imaging scan. Voxel-mirrored homotopic connectivity (VMHC) was employed to quantitatively describe bilateral functional connectivity. Analyses of variance (ANOVA) were performed to obtain brain regions with significant differences among three groups and then post hoc tests were calculated for inter-group comparisons.ResultsThe ANOVA revealed significant VMHC differences among three groups in the bilateral middle temporal gyrus (MTG), superior frontal gyrus (SFG), and inferior parietal lobule (IPL) (F = 10.47 ~ 15.09, p < 0.05, AlphaSim corrected). Relative to HCs, MDD with anhedonia showed significantly decreased VMHC in the bilateral MTG (t = -5.368, p < 0.05, AlphaSim corrected), as well as increased VMHC in the bilateral SFG (t = -4.696, p < 0.05, AlphaSim corrected). Compared to MDD without anhedonia, MDD with anhedonia showed significantly decreased VMHC in the bilateral MTG and IPL (t = -5.629 ~ -4.330, p < 0.05, AlphaSim corrected), while increased VMHC in the bilateral SFG (t = 3.926, p < 0.05, AlphaSim corrected). However, no significant difference was found between MDD without anhedonia and HCs.ConclusionThe present findings suggest that MDD with and without anhedonia exhibit different patterns of interhemispheric connectivity. Anhedonia in MDD is related to aberrant interhemispheric connectivity within brain regions involved in the frontal–temporal-parietal circuit.

Changes of anhedonia and cognitive symptoms in first episode of depression and recurrent depression, an analysis of data from NSSD

BackgroundAnhedonia and cognitive impairment are core features of major depressive disorder (MDD), and are essential to the treatment and prognosis. Here, we aimed to investigate anhedonia and its cognitive correlates between first episode of depression (FED) and recurrent depression (RD), which was part of the National Survey on Symptomatology of Depression. MethodsIn this study, 1400 drug naïve FED patients and 487 on medicine RD patients were included. Differences of anhedonia, cognitive symptoms and other clinical characteristics between groups were compared via Student's t-test, or the chi-square test as appropriate. Partial correlation analysis was used to analyze the correlations between anhedonia and cognitive symptoms after adjusting for potential confounders. A stepwise logistic regression analysis was performed to identify relapse risk factors among symptomatic variables, demographic factors, clinical characteristics and medication use. ResultsCompared to FED, RD patients displayed more comprehensive depressive, impaired cognitive and anhedonia symptoms. Cognitive symptoms were significantly related with the anhedonia symptoms with varying aspects. Patients taking emotional stabilizers displayed more abnormal cognitive symptoms, followed by benzodiazepines, and finally SSRIs, SNRIs and TCAs. The effect of drug use on anhedonia is not as extensive as that of cognitive symptoms. ConclusionCollectively, the results of this investigation advance the knowledge on changes in anhedonia and cognitive symptoms in MDD. LimitationsAs this is a cross sectional study, it is difficult to draw any causal conclusions between cognitive impairment and anhedonia in MDD, and to ascertain the worse cognitive performances identified here were induced by current drug use.

A Single Session of Bifrontal tDCS Can Improve Facial Emotion Recognition in Major Depressive Disorder: An Exploratory Pilot Study.

Emotional processing deficits are key features in major depressive disorder (MDD). Neuroimaging studies indicate that the dorsolateral prefrontal cortex (DLPFC) plays a pivotal role in both depressive symptoms and emotional processing. Recently, transcranial Direct Current Stimulations (tDCS) applied over the DLPFCs have held the promise to alleviate the symptoms in patients with MDD, but the effect on emotional processing in the patients is unclear. Here, we investigated the effect of a single session of tDCS over the DLPFCs on the emotional processing in patients with treatment-resistant MDD. In a randomized sham-controlled study, 35 patients received a single 30 min session of either active (2 mA, n = 18) or sham tDCS (n = 17). The anode was placed over the left and the cathode over the right DLPFC. Emotional processing accuracy was measured by a facial emotion recognition (FER) task. We observed an overall improvement in FER performance after the active tDCS, but not the sham tDCS. These exploratory results suggest that a single session of tDCS over the DLPFCs may improve FER in MDD, a crucial function of social cognition. Further studies are needed to investigate whether this acute improvement of FER in response to a single tDCS session could translate into clinical benefits or predict remission following repeated sessions of stimulation.

Characteristics of psychomotor retardation distinguishes patients with depression using multichannel near-infrared spectroscopy and finger tapping task

BackgroundPsychomotor retardation (PMR) is frequently noted as a characteristic feature of major depressive disorder (MDD). In patients with depression, it is characterized by retardation of speech, emotion, thinking, and cognition. This study explored the activation pattern of the prefrontal cortex (PFC) during the finger-tapping task (FTT) in subjects with MDD, aiming to provide additional understanding on the connection between PMR and PFC activation pattern in depression through the use of near-Infrared Spectroscopy (NIRS). We hypothesized that, through use of NIRS during the FTT, motor retardation in depression would generate a distinct PFC activation pattern, allowing for differentiation between patients with MDD and healthy controls (HCs). MethodsThirty-five patients with MDD and thirty-nine HCs underwent NIRS evaluation during performance of the FTT. The FTT included both left-finger tapping and right-finger tapping performed by a computer screen. Each participant was assessed using a 45-channel NIRS and various clinical scales. FindingsDuring the left-FTT, the left orbitofrontal cortex (OFC) showed higher oxy-hemoglobin (Oxy-Hb) activation in the MDD group when compared to the HCs. During the right-FTT, the right dorsolateral prefrontal cortex (DLPFC) demonstrated lower Oxy-Hb activation, and the dorsomedial prefrontal cortex (DMPFC) showed higher Oxy-Hb activation in the MDD group versus the HC group. ConclusionOur results demonstrated different activation patterns of the PFC between the MDD and HC groups, using FTT as a motor performance task. In particular, the OFC, the DLPFC and the DMPFC areas hold promise as new useful sites for such differentiation in future investigations.

Music and neuro-cognitive deficits in depression.

BackgroundCognitive deficits are one of the core features of major depressive disorder (MDD) that play crucial role in functional recovery. Studies have explored cognitive deficits in MDD, however, given inconsistent results, especially in mild-moderate MDD. Recently, studies have explored music as cognitive ability in various clinical conditions. In MDD, large focus has been on evaluating emotion deficits and just a handful on music cognition. With growing evidence on use of music based intervention to target cognitive deficits, it is imperative to explore nature of music cognitive ability in MDD.AimTo examine musical and neuro-cognitive deficits in patients with mild-moderate MDD.MethodsPatients diagnosed with mild or moderate MDD (n = 19) and matched healthy controls (HC) (n = 18) were evaluated on selected tests from NIMHANS Neuropsychological test battery and Montreal battery for evaluation of amusia (MBEA).ResultsMDD group performed significantly lower than HC on working memory (p = 0.007), verbal learning (p = 0.02) and retention (p = 0.03). Three indices were computed for a comprehensive evaluation. Groups did not differ significantly in any of the indices- focused attention, executive function, learning and memory as well as on music cognition. Focused attention and memory index predicted music cognition in HC and the combined group (MDD + HC) (p < 0.01). Attention alone contributed to 62.1% of variance in music cognition. Similarly, music cognition significantly predicted focused attention (p < 0.01).ConclusionIndividuals with mild-moderate MDD show significant deficits in working memory, verbal learning and memory, however, not in music cognition. There exists a significant relationship between music cognition and attention, which could be implicated in use of music interventions to ameliorate cognitive deficits. Limitations of study include small sample size and heterogeneity. Future studies on larger cohort examining musical emotion perception and neurocognition is imperative to have deeper understanding of this debilitating condition.

Response to unexpected social inclusion: A study using the cyberball paradigm.

BackgroundDysfunctional expectations are considered core characteristics of Major Depressive Disorder (MDD) and should be focused in psychotherapy. Dysfunctional expectations are especially pronounced in the interpersonal area (social expectations). In the present study, we examine the effect of unexpected social inclusion (expectation violation) on the change of generalized and specific depression-typical social expectations.MethodWe conducted an online study to investigate the impact of social inclusion after a period of social exclusion (unexpected social inclusion) on social expectation change (sample size 144) in a non-clinical sample. Depressive symptoms were assessed via self-reporting. Participants took part in two rounds of the online ball-game Cyberball. In the first round, all participants were socially excluded by their two co-players (acquisition of negative social expectations). In the second round, participants were either once more excluded (expectation confirmation) or included equally (expectation violation) by the same co-players. Specific and generalized social expectations were assessed after each round.ResultsSpecific and generalized social expectations increased following expectation violation. Even though depressive symptoms were related to lower levels of social expectations, we found that depressive symptoms did not moderate expectation change after positive expectation violations.ConclusionsIn the present experimental setup including the use of the online ball-game Cyberball, the establishment and change of social expectations can be experimentally manipulated. Under the given circumstances and in a non-clinical sample, negative expectations can be updated after unexpected positive experiences regardless of the number of depressive symptoms. The results are discussed in the context of current models of Major Depressive Disorder (MDD), expectation change, and cognitive behavioral therapy.

The association between overweight/obesity and poor cognitive function is mediated by inflammation in patients with major depressive disorder

BackgroundCognitive dysfunction is a common and core feature of major depressive disorder (MDD). Evidences exerted a potentially harmful role of obesity and higher peripheral levels of inflammation in cognitive function, but few studies have explored whether markers of peripheral inflammation might mediate the association between overweight/obesity and deficits in cognitive function. Our study aimed to examine the cognitive function in MDD patients and clarify the effects of overweight/obesity and inflammatory cytokines on cognitive dysfunction in this population. MethodWe used a cross-sectional design in this study. A total of 265 patients with MDD were enrolled and divided into underweight, normal weight and overweight/obese groups. The MATRICS Consensus Cognitive Battery (MCCB) was administered to measure the cognition. Plasma levels of nineteen cytokines were measured using high sensitivity multiplex bead-based assays. ResultsWe found overweight/obese MDD patients associated with higher plasma levels of tumor necrosis factor (TNF)-α, interleukin (IL)-8, and macrophage inflammatory protein (MIP)-1β and worse performance in speed of processing and working memory. The mediation analysis found higher levels of IL-8 (direct: β = −0.591 (95 % Confidence Interval (CI): −1.0 to −0.2), P = 0.002; indirect: β = 0.060 (95 % CI.: 0.0–0.2), P = 0.032) and TNF-α (direct: β = −0.589 (95 % CI.: −1.0 to −0.2), P = 0.002; indirect: β = 0.059 (95 % CI.: 0.1–0.2), P = 0.037) were associated with more deficits in speed of processing, and partially mediated the relationship between body mass index and speed of processing. ConclusionOur results suggest that elevated inflammation might be one biological mechanism underlying the link between higher body mass and deficits in processing speed in patients with MDD.