Domain-specific impairment in cognitive control among remitted youth with a history of major depression

Early Emergence of Rumination has no Association with Performance on a Non-affective Inhibitory Control Task

Rumination is a vulnerability for depression and potentially linked to inhibitory control weaknesses. We aimed to replicate the association observed in adults between inhibitory control and rumination in adolescents, and to examine putative moderating roles of childhood maltreatment and perceived family cohesion in an adolescent sample at risk for depression due to familial/personal history. Ninety adolescents aged 11-17 (M = 14.6, SD = 1.8) completed self-report scales of rumination, maltreatment, and family cohesion, and performed a task assessing inhibitory control. Hierarchical regression models showed no significant relation between inhibitory control and moderator variables on rumination. However, adolescents who reported higher levels of maltreatment and who perceived lower family cohesion tended to indicate higher levels of rumination (BChilhood Maltreatment = 27.52, 95% CIs [5.63, 49.41], BFamily Cohesion = -0.40, 95% CIs [-0.65, -0.15]). These findings demonstrate an alternative understanding of factors that increase depression onset risk and recurrence in adolescents.

Cognitive functioning in children and adolescents with depression: A systematic review and meta-analysis

Although cognitive dysfunction is associated with depression in adults, the link in children and adolescents is unclear. This systematic review and meta-analysis quantifies the association between depression and cognitive function in children and adolescents. Systematic searches were conducted in six databases: Child Development and Adolescent Studies, Ovid MEDLINE, Ovid Embase, Ovid APA PsycINFO, EBSCO CINAHL Plus, Scopus (last search: April 2023). Studies including measures of cognitive outcomes (memory, attention, executive function, processing speed, language) among children (≤18 years) with depression were included. The Joanna Briggs Institute Critical Appraisal Tools were used to determine study risk of bias. Random-effects meta-analyses of study outcomes were performed. Seventeen studies were included (15 were cross-sectional, 1 prospective, 1 randomized control trial). Participants (N = 13,567) were 10 to 17 years old (mean 13.8 ± 2.2 years; 60 % female). Compared with healthy controls, depressed participants had lower performance on tests of working memory (g = -0.40; 95 % CI: -0.67, -0.13), long-term memory (g = -0.48; 95 % CI: -0.72, -0.25), attention (g = -0.15; 95 % CI: -0.26, -0.04), executive function (g = -0.16; 95 % CI: -0.24, -0.08), and language (g = -0.23; 95 % CI: -0.36, -0.09). No performance differences were observed on tests of short-term memory or processing speed. Children and adolescents with depression demonstrated lower performance on tests of working and long-term memory, attention, executive function and language. These findings emphasize the importance of considering cognitive functioning among children with depression, and greater understanding of the effect of treatment on these outcomes. PROSPERO (CRD42022332064).

Change on the Repeatable Battery for the Assessment of Neuropsychological Status and its relationship to brain amyloid

BACKGROUND

The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has been associated with commonly used biomarkers of Alzheimer's disease (AD), including brain amyloid plaque density. However, less is known about if changes in the RBANS across time are also related to brain amyloid deposition. The current study sought to expand on prior work by examining the relationship between changes over time on the RBANS and amyloid deposition via positron emission tomography (PET).

METHOD

One-hundred twenty-six older adults with intact or impaired cognition and daily functioning underwent repeat assessment with the RBANS across nearly 16 months, as well as had a baseline amyloid PET scan.

RESULTS

In the entire sample, amyloid deposition was significantly related to change on all five Indexes and the Total Scale score of the RBANS, with greater amyloid being associated with worsening cognition. This pattern was also observed in 11 of 12 subtests.

CONCLUSIONS

Whereas prior studies have identified a relationship between baseline RBANS and amyloid status, the current findings support that changes in the RBANS are also indicative of AD brain pathology, even if these findings are mediated by cognitive status. Although replication in a more diverse sample is needed, these results continue to support the use of the RBANS in AD clinical trials.

Repeatable battery for the assessment of neuropsychological status and its relationship to biomarkers of Alzheimer's disease

The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has been associated with commonly used biomarkers of Alzheimer's disease (AD). However, prior studies have typically utilized small and poorly characterized samples, and they have not analyzed the subtests of the RBANS. The current study sought to expand on prior work by examining the relationship between the Indexes and subtest scores of the RBANS and three AD biomarkers: amyloid deposition via positron emission tomography, hippocampal volume via magnetic resonance imaging, and APOE ε4 status.

One-hundred twenty-one older adults across the AD continuum (intact, amnestic Mild Cognitive Impairment, mild AD), who were mostly Caucasian and well-educated, underwent assessment with the RBANS and collection of the three biomarkers.

Greater amyloid deposition was significantly related to lower scores on all five Indexes and the Total Scale score of the RBANS, as well as 11 of 12 subtests. For bilateral hippocampal volume, significant correlations were observed for 4 of the 5 Indexes, Total Scale score, and 9 of 12 subtests, with smaller hippocampi being related to lower RBANS scores. Participants with at least one APOE ε4 allele had significantly lower scores on 3 of the 5 Indexes, Total Scale score, and 8 of the 12 subtests.

In this sample of participants across the dementia spectrum, most RBANS Indexes and subtests showed relationships with the amyloid deposition, hippocampal volumes, and APOE status, with poorer performance on the RBANS being associated with biomarker positivity. Although memory scores on the RBANS have traditionally been linked to biomarkers in AD, other Index and subtest scores also hold promise as indicators of AD. Replication in a more diverse sample is needed.

Current Evidence and Theories in Understanding the Relationship between Cognition and Depression in Childhood and Adolescence: A Narrative Review

The present narrative review has covered the current evidence regarding the role of cognitive impairments during the early phase of major depressive disorder (MDD), attempting to describe the cognitive features in childhood, adolescence and in at-risk individuals. These issues were analyzed considering the trait, scar and state hypotheses of MDD by examining the cold and hot dimensions, the latter explained in relation to the current psychological theoretical models of MDD. This search was performed on several electronic databases up to August 2022. Although the present review is the first to have analyzed both cold and hot cognitive impairments considering the trait, scar and state hypotheses, we found that current evidence did not allow to exclusively confirm the validity of one specific hypothesis since several equivocal and discordant results have been proposed in childhood and adolescence samples. Further studies are needed to better characterize possible cognitive dysfunctions assessing more systematically the impairments of cold, hot and social cognition domains and their possible interaction in a developmental perspective. An increased knowledge on these topics will improve the definition of clinical endophenotypes of enhanced risk to progression to MDD and, to hypothesize preventive and therapeutic strategies to reduce negative influences on psychosocial functioning and well-being.

Neurocognitive deficits in depression: a systematic review of cognitive impairment in the acute and remitted state

Previous research suggests a broad range of deficits in major depressive disorder. Our goal was to update the current assumptions and investigate the extent of cognitive impairment in depression in the acute and remitted state. A systematic review of the existing literature between 2009 and 2019 assessing the risk of bias within the included studies was performed. Of the 42 articles reviewed, an unclear risk of bias was shown overall. The risk of bias mainly concerned the sample selection, inadequate remedial measures, as well as the lack of blinding the assessors. In the acute phase, we found strong support for impairment in processing speed, learning, and memory. Follow-up studies and direct comparisons revealed less pronounced deficits in remission, however, deficits were still present in attention, learning and memory, and working memory. A positive correlation between the number of episodes and cognitive deficits as well as depression severity and cognitive deficits was reported. The results also demonstrate a resemblance between the cognitive profiles in bipolar disorder and depression. Comparisons of depression with schizophrenia led to unclear results, at times suggesting an overlap in cognitive performance. The main findings support the global deficit hypothesis and align with results from prior meta-analyses and reviews. Recommendations for future research are also presented.

Infralimbic BDNF signaling is necessary for the beneficial effects of extinction on set shifting in stressed rats

Current pharmacotherapies for posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) are ineffective for many patients, and often do not restore cognitive dysfunction associated with these disorders. Behavioral therapies, such as exposure therapy, can be effective for treatment-resistant patients. The mechanisms underlying exposure therapy are not well-understood. Fear extinction as an intervention after chronic stress can model the beneficial effects of exposure therapy in rats. Extinction requires neuronal activity and protein synthesis in the infralimbic (IL) cortex for its beneficial effects. We hypothesized that extinction requires Brain-Derived Neurotrophic Factor (BDNF) activity in the IL cortex to reverse stress-induced cognitive flexibility impairments. Extinction learning reversed set-shifting deficits induced by Chronic Unpredictable Stress (CUS), tested 24 h after extinction. Blocking BDNF signaling in the IL cortex during extinction by local administration of a neutralizing antibody prevented the beneficial effects of extinction on set shifting after stress. Extinction induced activation of the BDNF TrkB receptor, and signaling pathways associated with BDNF (Akt and Erk). Administration of exogenous BDNF into IL cortex in the absence of extinction was sufficient to reverse the effects of stress on set shifting. The effects of extinction were prevented by blocking either Erk or Akt signaling in the IL cortex, whereas the effects of exogenous BDNF were dependent on Erk, but not Akt, signaling. Our observations suggest that BDNF-Erk signaling induced by extinction underlies plastic changes that can reverse or counteract the effects of chronic stress in the IL cortex.

Cognitive Impairment and Neurocognitive Profiles in Major Depression-A Clinical Perspective

Increasingly, studies have investigated cognitive functioning from the perspective of acute state- to remitted phases of Major Depressive Disorder (MDD). Some cognitive deficits observed in the symptomatic phase persist in remission as traits or scars. The etiological origin and clinical consequences of the neurocognitive profiles reported in the literature are still unclear and may vary across populations. Deficits are suspected to influence the association between MDD and neurodegenerative disorders and could thus be of particular clinical consequence. The aim of this review is to describe the clinical neuropsychological profile in MDD and how it is related to research during the past decade on cognitive deficits in MDD from a state, trait, and scar perspective. This review, with a clinical perspective, investigates research from the past decade regarding cognitive functioning in MDD in a long-term perspective. We focus on the clinical manifestation of deficits, and the potential neurodegenerative consequences of the neurocognitive profile in MDD. Searches in Medline, PsycINFO and Embase were conducted targeting articles published between 2010 and 2020. Examination of the evidence for long-lasting neurocognitive deficits in major depression within the cognitive domains of Memory, Executive Functions, Attention, and Processing Speed was conducted and was interpreted in the context of the State, Scar and Trait hypotheses. Defining the neurocognitive profiles in MDD will have consequences for personalized evaluation and treatment of residual cognitive symptoms, and etiological understanding of mood disorders, and treatments could potentially reduce or delay the development of neurodegenerative disorders.

Inflammatory cytokines, cognition, and response to antidepressant treatment in patients with major depressive disorder

BACKGROUND

Inflammation and cognition are related to major depressive disorder (MDD), but the role in treatment response remains unclear. In this study, we investigated correlation between inflammatory cytokines and cognition in MDD patients treated with antidepressant medication.

METHODS

The participants were 149 MDD patients. Cytokines before therapy, cognitive assessments and severity of depression before and after therapy were tested. Logistic regression was used to explore underlying risks treatment response.

RESULTS

There were significant differences in smoking, alcohol drinking, and Stroop Color Test(SCT), Stroop Color-Word Test (SCWT), and Continuous Performance Test(CPT) scores between response group (RG) and non-response group (NRG) at baseline. Performance of patients in RG improved more in Brief Assessment of Cognition in Schizophrenia (BACS), Color Trial Test-I (CTT-I), SCT and SCWT after treatment. Levels of baseline IL-18 were associated with baseline learning and memory, and executive function. Treatment response was associated with drinking, performance of CPT and SCT.

CONCLUSION

MDD patients with different treatment responses have different cognitive defects, especially in speed of processing and executive function. Expression of cytokines is associated with cognition and may influence treatment response. Better speed of processing and executive function, and poorer attention at baseline may respond better to antidepressant treatment.

Set Shifting and Inhibition Deficits as Potential Endophenotypes for Depression

The etiology of Major Depressive Disorder (MDD) is poorly understood, and identifying endophenotypes, or intermediate processes implicated in pathophysiology, for MDD may inform treatment and identification/prevention efforts. Impaired set-shifting and inhibition are commonly observed in MDD; however, few studies have examined they are endophenotypes for MDD. Thus, the present study tested whether set-shifting and/or inhibition satisfy several endophenotype criteria: specifically, whether they were (1) impaired in current MDD, (2) impaired in remitted MDD, and (3) familial (i.e., correlated within sibling pairs). Set-shifting and inhibition were assessed using subtests from the Delis-Kaplan Executive Function System. Psychopathology was assessed using the Structured Clinical Interview for DSM-5. Results indicated set-shifting deficits were familial and present in both current MDD and in remitted MDD individuals who had no current disorders, suggesting they may be state-independent. Inhibition was familial, but was generally not impaired in current nor remitted MDD (although the remitted MDD group with no current disorders exhibited impairments on one of the two inhibition tasks). These findings indicate that impaired set-shifting is a promising endophenotype candidate for MDD. Findings are limited to young adults, and further research is needed to test generalizability to other populations, evaluate longitudinal relationships, and examine other endophenotype criteria.

The MATRICS Consensus Cognitive Battery: Psychometric Properties of the Chinese Version in Young Patients With Major Depression Disorder

Background: Young patients with major depressive disorder are also associated with cognitive deficits. The development of an accurate and effective battery to measure cognitive impairment in young patients with major depressive disorder (Y-MDD) is necessary for both research and clinical practice. This study was designed to test the psychometric properties of the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery (MCCB) in Y-MDD. Method: Fifty Y-MDD patients, 38 euthymic young patients with bipolar disorder (Y-BD), and 51 healthy teenagers were recruited. The MCCB and the Montreal Cognitive Assessment (MoCA) were administered to assess cognitive impairment at baseline. The MCCB was also assessed 2 weeks later in Y-MDD patients. All subjects were between the ages of 13 and 24 years. Result: In the current study, cognitive impairment was greater in Y-BD patients than in Y-MDD patients in some domains. The MCCB has good internal consistency and reliability in Y-MDD patients. The Pearson correlation coefficients for retest reliability were good. Our findings also revealed an acceptable correlation between the MCCB and the MoCA, indicating good concurrent validity of the MCCB. Furthermore, exploratory factor analysis of the MCCB in Y-MDD patients revealed five domains with acceptable internal structures. Conclusion: The MCCB has acceptable psychometric properties and is a sensitive battery of cognitive impairment in Y-MDD patients. In the future, additional studies need to be carried out with larger samples while controlling for the use of psychotropic medications and antidepressants to validate the findings of the present study.

A Longitudinal 5-Year Follow-Up Study of Cognitive Function After First Episode Major Depressive Disorder: Exploring State, Scar and Trait Effects

Major depression (MDD) is associated with cognitive deficits in processing speed and executive function (EF) following first episode (FE). It is unclear whether deficits are state or trait related. Studies following FE MDD over longer periods are lacking, making it uncertain how cognition and symptoms develop after the initial episode. The present study assessed cognitive function and symptoms 5 years following FE MDD. In addition, the study explored relationships between MDD symptoms, rumination, and cognitive deficits with regards to the trait, state, and scar perspective. Twenty-three participants with previous FE MDD, and 20 matched control participants were compared on Delis-Kaplan Executive Function System measures of processing speed and EF, in a 5-year longitudinal follow-up study. Correlations between current symptoms- and history of MDD, rumination, cognition were investigated. Findings indicated that cognitive deficits persisted with no clear signs of exacerbation after initial episode. Inhibition appeared independent of current and previous symptoms of depression. Processing speed was related to depressive- symptoms and rumination. In conclusion, results indicated persisting, stable deficits in both EFs and processing speed. Findings further suggest that depressive symptoms could be related to deficits in processing speed, indicating state effects. There was limited support for worsening of cognition after initial episode. Some aspects of EF like Inhibition could show persistent deficits independent of depressive symptoms indicating trait effects.

Disentangling vulnerability, state and trait features of neurocognitive impairments in depression

Depression is a debilitating disorder that often starts manifesting in early childhood and peaks in onset during adolescence. Neurocognitive impairments have emerged as clinically important characteristics of depression, but it remains controversial which domains specifically index pre-existing vulnerability, state-related or trait-related markers. Here, we disentangled these effects by analysing the Adolescent Brain Cognitive Development dataset (n = 4626). Using information of participants' current and past mental disorders, as well as family mental health history, we identified low-risk healthy (n = 2100), high-risk healthy (n = 2023), remitted depressed (n = 401) and currently depressed children (n = 102). Factor analysis of 11 cognitive variables was performed to elucidate latent structure and canonical correlation analyses conducted to probe regional brain volumes reliably associated with the cognitive factors. Bayesian model comparison of various a priori hypotheses differing in how low-risk healthy, high-risk healthy, remitted depressed and currently depressed children performed in various cognitive domains was performed. Factor analysis revealed three domains: language and reasoning, cognitive flexibility and memory recall. Deficits in language and reasoning ability, as well as in volumes of associated regions such as the middle temporal and superior frontal gyrus, represented state- and trait-related markers of depression but not pre-existing vulnerability. In contrast, there was no compelling evidence of impairments in other domains. These findings-although cross-sectional and specific to 9-10-year-old children-might have important clinical implications, suggesting that cognitive dysfunction may not be useful targets of preventive interventions. Depressed patients, even after remission, might also benefit from less commonly used treatments such as cognitive remediation therapy.

A Lifespan Model of Interference Resolution and Inhibitory Control: Risk for Depression and Changes with Illness Progression

The cognitive processes involved in inhibitory control accuracy (IC) and interference resolution speed (IR) or broadly - inhibition - are discussed in this review, and both are described within the context of a lifespan model of mood disorders. Inhibitory control (IC) is a binary outcome (success or no for response selection and inhibition of unwanted responses) for any given event that is influenced to an extent by IR. IR refers to the process of inhibition, which can be manipulated by task design in earlier and later stages through use of distractors and timing, and manipulation of individual differences in response proclivity. We describe the development of these two processes across the lifespan, noting factors that influence this development (e.g., environment, adversity and stress) as well as inherent difficulties in assessing IC/IR prior to adulthood (e.g., cross-informant reports). We use mood disorders as an illustrative example of how this multidimensional construct can be informative to state, trait, vulnerability and neuroprogression of disease. We present aggregated data across numerous studies and methodologies to examine the lifelong development and degradation of this subconstruct of executive function, particularly in mood disorders. We highlight the challenges in identifying and measuring IC/IR in late life, including specificity to complex, comorbid disease processes. Finally, we discuss some potential avenues for treatment and accommodation of these difficulties across the lifespan, including newer treatments using cognitive remediation training and neuromodulation.

Is cognitive dysfunction involved in difficult-to-treat depression? Characterizing resistance from a cognitive perspective

BACKGROUND

This study aimed to identify clinical and cognitive factors associated with increased risk for difficult-to-treat depression (DTD) or treatment-resistant depression (TRD).

METHODS

A total of 229 adult outpatients with major depression were recruited from the mental health unit at a public hospital. Participants were subdivided into resistant and nonresistant groups according to their Maudsley Staging Model score. Sociodemographic, clinical, and cognitive (objective and subjective measures) variables were compared between groups, and a logistic regression model was used to identify the factors most associated with TRD risk.

RESULTS

TRD group patients present higher verbal memory impairment than the nonresistant group irrespective of pharmacological treatment or depressive symptom severity. Logistic regression analysis showed that low verbal memory scores (odds ratio [OR]: 2.02; 95% confidence interval [CI]: 1.38-2.95) together with high depressive symptom severity (OR: 1.29; CI95%: 1.01-1.65) were associated with TRD risk.

CONCLUSIONS

Our findings align with neuroprogression models of depression, in which more severe patients, defined by greater verbal memory impairment and depressive symptoms, develop a more resistant profile as a result of increasingly detrimental neuronal changes. Moreover, our results support a more comprehensive approach in the evaluation and treatment of DTD in order to improve illness course. Longitudinal studies are warranted to confirm the predictive value of verbal memory and depression severity in the development of TRD.

Decreased working memory capacity among individuals with a mood disorder who have increased metabolic burden

BACKGROUND

Individuals with mood disorders experience a higher rate of obesity than the general population, putting them at risk for poorer outcomes. The relationship between obesity and a core feature of the mood disorders, neurocognition, is less understood. We examined the interaction of obesity as indexed by body mass index (BMI) and working memory performance in a large sample of individuals with bipolar disorder (BD), major depressive disorder (MDD), and healthy controls (HC).

METHODS

Participants with BD (n = 133), MDD (n = 78), and HC (n = 113) (age range 18-40) completed a spatial working memory (SWM) task that included three-graded increases in the number of target locations. Participants were subdivided by BMI classification into six diagnostic-BMI (BMI groups: Normal Weight, Overweight/Obese) subgroups. Performance on the task was indexed by number of errors within each difficulty level.

RESULTS

The number of errors, across all groups, increased with task difficulty. There was an interaction between errors and diagnostic-BMI group. Post-hoc analyses indicated that while the Normal Weight-BD group did not differ in performance from the other groups, the Overweight/Obese-BD group performed significantly worse than HC groups.

LIMITATIONS

Metabolic effects of psychotropic medications due to the naturalistic nature of the study, younger age of the MDD sample, and utilizing self-reported indicators of obesity may limit generalizability.

CONCLUSIONS

Individuals with BD with increased metabolic burden exhibit increased working memory errors than non-psychiatric controls who also have increased metabolic burden. Future work could address prevention and amelioration of such difficulties to reduce associated functional morbidity.

Cognitive functioning in ultra-high risk for psychosis individuals with and without depression: Secondary analysis of findings from the NEURAPRO randomized clinical trial

Neurocognitive impairments are well established in both ultra-high risk (UHR) for psychosis and major depressive disorder (MDD). Despite this understanding, investigation of neurocognitive deficits in UHR individuals with MDD and its association with MDD within this population, has been scarce. Hence, this study aimed to examine any differences in neurocognition at baseline between those with MDD at baseline and those with no history of MDD, as well as determine whether neurocognitive variables are significantly associated with meeting criteria for MDD at follow-up, while controlling for relevant clinical variables, within a UHR cohort. Data analysis was conducted on 207 participants whose baseline neurocognition was assessed using Brief Assessment of Cognition for Schizophrenia, as part of a trial of omega-3 fatty acids (NEURAPRO) for UHR individuals. While baseline MDD was the strongest predictor, poorer verbal memory and higher verbal fluency were significantly associated with MDD at 12 months (p = .04 and 0.026, respectively). Further, higher processing speed was significantly associated with MDD at medium-term follow-up (p = .047). These findings outline that neurocognitive skills were independently associated with meeting criteria for MDD at follow-up within UHR individuals, with novel findings of better verbal fluency and processing speed being linked to MDD outcomes. Hence, neurocognitive performance should be considered as a marker of risk for MDD outcomes and a target for management of MDD in UHR.

Questioning the Effort Hypothesis That Depressed Patients Perform Disproportionately Worse on Effortful Cognitive Tasks

The debate over Hasher and Zacks’ effort hypothesis—that performance on effortful tasks by patients with depression will be disproportionately worse than their performance on automatic tasks—shows a need for additional research to settle whether or not this notion is “clinical lore.” In this study, we categorized 285 outpatient recipients of neuropsychological evaluations into three groups—No Depression, Mild-to-Moderate Depression, and Severe Depression—based on their Beck Depression Inventory-2 self-reports. We then compared these groups’ performances on both “automatic” and “effortful” versions of the Ruff 2 & 7 Selective Attention Test Total Speed and Total Accuracy Indices, the Digit Span subtest from the Wechsler Adult Intellectual Scale—Fourth Edition, and Trail Making Test Parts A and B, using a two-way (3 × 2) mixed multivariate analysis of variance. Patients with Mild-to-Moderate Depression or Severe Depression performed disproportionately worse than patients with No Depression in our sample on more effortful versions of only one of the four attention or executive functioning measures (Trail Making Test). Thus, these data failed to fully support a hypothesis of disproportionately worse performance on more effortful tasks. While this study failed to negate the effort hypothesis in some specific instances, particularly for use in the Trail Making Test, there is cause for caution in routinely applying the effort hypothesis when interpreting test findings in most clinical settings and for most measures.

Predictors of Attrition in Longitudinal Neuroimaging Research: Inhibitory Control, Head Movement, and Resting-State Functional Connectivity

Attrition is a major problem in longitudinal neuroimaging studies, as it may lead to unreliable estimates of the stability of trait-like processes over time, of the identification of risk factors for clinical outcomes, and of the effects of treatment. Identification of characteristics associated with attrition has implications for participant recruitment and participant retention to achieve representative longitudinal samples. We investigated inhibitory control deficits, head motion, and resting-state functional connectivity within the cognitive control network (CCN) as predictors of attrition. Ninety-seven individuals with remitted major depressive disorder or healthy controls completed a functional magnetic resonance imaging scan, which included a go/no-go task and resting-state functional connectivity. Approximately 2 months later, participants were contacted and invited to return for a second scan. Seventeen individuals were lost to follow-up or declined to participate in the follow-up scan. Worse inhibitory control was correlated with greater movement within the scanner, and each predicted a greater likelihood of attrition, with movement mediating the effects of inhibitory control on attrition. Individuals who dropped out of the study exhibited greater movement than nondropouts across 9 of the 14 runs of the scan, with medium-to-large effect sizes. Finally, exploratory analyses suggested that attenuated resting-state connectivity with the CCN (particularly in bilateral dorsolateral prefrontal cortex) was associated with greater likelihood of attrition after accounting for head motion at several levels of analysis. Inhibitory control and movement within the scanner are associated with attrition, and should be considered for strategic oversampling and participant retention strategies to ensure generalizability of results in longitudinal studies.

The Titrated Monetary Incentive Delay Task: Sensitivity, convergent and divergent validity, and neural correlates in an RDoC sample

INTRODUCTION

Neuropsychological tests are designed to assay brain function via performance measurements. Many tests corresponding to visual and motor cortex function have been validated. Tests probing reward circuitry, including the ventral striatum (VS), could benefit assessment of numerous neurological and psychiatric disorders in which reward or VS function is disturbed. The present study sought to examine convergent and divergent validity of our modified, titrated version of the Monetary Incentive Delay Task, such that it may in the future stand as a validated neuropsychological test for reward function.

METHOD

Participants were 132 individuals with a history of mood disturbance (HMD) and 43 healthy comparisons, ages 18-30 years. In addition to a standard neuropsychological battery and symptom measures, participants completed a modified version of the Monetary Incentive Delay Task (T-MIDT) during functional magnetic resonance imaging (fMRI), which involved a multistage titration procedure to incrementally increase or decrease the response window time per each participant's psychomotor speed and optimize individual performance.

RESULTS

Across groups after titration, performance on the T-MIDT diverged from measures of processing speed, attention, and spatial working memory, but not inhibitory control. Performance in the HMD group was differentially correlated with executive function measures before and after titration. The reward circuit (e.g., subcortical, insular, medial prefrontal) was activated during reward anticipation.

CONCLUSION

The present findings provide preliminary evidence that the T-MIDT measures a construct distinct from many executive functions and that individualized titration of the task parameters is critical in parsing reward from executive function. The T-MIDT correlated with residual mood symptoms in individuals with remitted depression or bipolar disorder, implying that behavioral or brain activation group differences are only to be observed in the active state of illness.

Cognitive control and network disruption in remitted depression: a correlate of childhood adversity

Individuals in a major depressive episode often display impairment in cognitive control, and this impairment exists outside of the acute phase of illness. Impairment in cognitive control also has been associated with exposure to childhood adversity (CA). The current study examined whether exposure to CA can explain variance in a component of cognitive control—inhibitory control—independent of diagnostic status in young adults with and without a history of depression. Healthy control individuals (n = 40) and individuals with remitted major depressive disorder (n = 53) completed a task measuring inhibitory control, reported level of CA and completed a scanning session to assess gray matter volume and resting state connectivity in regions associated with cognitive control. The results demonstrate that higher levels of CA were associated with poorer inhibitory control, reduced right middle frontal gyrus gray matter, decreased connectivity of salience and emotion networks and increased connectivity in cognitive control networks, even after controlling for diagnostic status, residual depression symptoms and current stressors. Together, the results suggest that inhibitory control impairment and intrinsic connectivity changes may be characterized as developmental sequelae of early stress exposure.

Cognitive Control as a 5-HT1A-Based Domain That Is Disrupted in Major Depressive Disorder

Heterogeneity within Major Depressive Disorder (MDD) has hampered identification of biological markers (e.g., intermediate phenotypes, IPs) that might increase risk for the disorder or reflect closer links to the genes underlying the disease process. The newer characterizations of dimensions of MDD within Research Domain Criteria (RDoC) domains may align well with the goal of defining IPs. We compare a sample of 25 individuals with MDD compared to 29 age and education matched controls in multimodal assessment. The multimodal RDoC assessment included the primary IP biomarker, positron emission tomography (PET) with a selective radiotracer for 5-HT1A [(11C)WAY-100635], as well as event-related functional MRI with a Go/No-go task targeting the Cognitive Control network, neuropsychological assessment of affective perception, negative memory bias and Cognitive Control domains. There was also an exploratory genetic analysis with the serotonin transporter (5-HTTLPR) and monamine oxidase A (MAO-A) genes. In regression analyses, lower 5-HT1A binding potential (BP) in the MDD group was related to diminished engagement of the Cognitive Control network, slowed resolution of interfering cognitive stimuli, one element of Cognitive Control. In contrast, higher/normative levels of 5-HT1A BP in MDD (only) was related to a substantial memory bias toward negative information, but intact resolution of interfering cognitive stimuli and greater engagement of Cognitive Control circuitry. The serotonin transporter risk allele was associated with lower 1a BP and the corresponding imaging and cognitive IPs in MDD. Lowered 5HT 1a BP was present in half of the MDD group relative to the control group. Lowered 5HT 1a BP may represent a subtype including decreased engagement of Cognitive Control network and impaired resolution of interfering cognitive stimuli. Future investigations might link lowered 1a BP to neurobiological pathways and markers, as well as probing subtype-specific treatment targets.

Magnitude and correlates of cognitive impairment among major depressive disorder patients in Addis Ababa: institution based cross-sectional study

Objective

Cognitive impairments are now widely recognized and emerging as an important therapeutic target in a patient with a major depressive disorder (MDD). It associated with a more deteriorating course of illness among MDD patients. Therefore, understanding the level of cognitive impairment and associated factors is crucial to provide optimal care for MDD patients.

Result

The proportion of cognitive impairment among MDD patients was found to be 54.4% (95%, CI (49.6, 59.3). Factors significantly associated with having cognitive impairment were age adjusted odds ratio (AOR) = 3.00, 95%, confidence interval (CI): (1.49, 6.03), educational status, (AOR = 5.36, 95% CI 2.16, 13.26), employment status (AOR = 3.63, 95 CI 1.99, 6.62), duration of the illness (AOR = 3.16, 95% CI 1.31, 7.64), having co-morbid psychiatric illnesses (AOR = 2.16, 95% CI 1.26, 3.71), and illness relapse (AOR = 2.97, 95% CI 1.54, 5.73).

Electronic supplementary material

The online version of this article (10.1186/s13104-019-4184-5) contains supplementary material, which is available to authorized users.

Differential engagement of cognitive control regions and subgenual cingulate based upon presence or absence of comorbid anxiety with depression

BACKGROUND

Major depressive disorder (MDD) and anxiety disorders are highly comorbid, sharing many similar symptoms, including impairments in cognitive control. Deficits in cognitive control could be a potential mechanism underlying impaired emotion regulation in mood disorders.

METHODS

Participants were 44 individuals with no history of mental illness (healthy controls, HC), 31 individuals in the remitted state of MDD (rMDD), and 18 individuals who met lifetime DSM-IV-TR criteria for rMDD and an anxiety disorder in remission (Comorbid). Participants completed a Parametric Go/No-Go (PGNG) test during fMRI. Event-related analyses modeled activity for cognitive control successes (Hits for Targets, Rejections for Lures) and failures (Commissions on Lures) on the PGNG task.

RESULTS

The rMDD group showed significantly reduced activity within the cognitive control network (CCN) during Commission errors, including the middle frontal gyrus and inferior parietal lobule (IPL). The Comorbid group showed significantly reduced activity in several clusters within the CCN during correct Rejections, including the left IPL and right inferior frontal gyrus and greater subgenual cingulate. Notably, during correct Rejections, 60% of activation for the Comorbid group was within the Salience and Emotion Network (SEN), with 0% within the CCN.

LIMITATIONS

The size of the Comorbid subgroup was modest, preventing subanalysis of the different AD subtypes.

CONCLUSIONS

There is evidence that CCN activity declines in rMDD and that there may be compensatory SEN activity in individuals with Comorbid rMDD and anxiety. Our findings support the identification of comorbid anxiety as a meaningful subtype of MDD that may obscure group differences between rMDD and HCs.

Cognitive control neuroimaging measures differentiate between those with and without future recurrence of depression

Background

Major Depressive Disorder (MDD) is a prevalent, disruptive illness. A majority of those with MDD are at high risk for recurrence and increased risk for morbidity and mortality. This study examined whether multimodal baseline (and retest) Cognitive Control performance and neuroimaging markers (task activation and neural connectivity between key brain nodes) could differentiate between those with and without future recurrence of a major depressive (MD) episode within one year. We hypothesized that performance and neuroimaging measures of Cognitive Control would identify markers that differ between these two groups.

Methods

A prospective cohort study of young adults (ages 18–23) with history (h) of early-onset MDD (N = 60), now remitted, and healthy young adults (N = 49). Baseline Cognitive Control measures of performance, task fMRI and resting state connectivity (and reliability retest 4–12 weeks later) were used to compare those with future recurrence of MDD (N = 21) relative to those without future recurrence of MDD (N = 34 with resilience). The measures tested were (1) Parametric Go/No-Go (PGNG) performance, and task activation for (2) PGNG Correct Rejections, (3) PGNG Commission errors, and (4 & 5), resting state connectivity analyses of Cognitive Control Network to and from subgenual anterior cingulate.

Results

Relative to other groups at baseline, the group with MDD Recurrence had less bilateral middle frontal gyrus activation during commission errors. MDD Recurrence exhibited greater connectivity of right middle frontal gyrus to subgenual anterior cingulate (SGAC). SGAC connectivity was also elevated in this group to numerous regions in the Cognitive Control Network. Moderate to strong ICCs were present from test to retest, and highest for rs-fMRI markers. There were modest, significant correlations between task, connectivity and behavioral markers that distinguished between groups.

Conclusion

Markers of Cognitive Control function could identify those with early course MD who are at risk for depression recurrence. Those at high risk for recurrence would benefit from maintenance or preventative treatments. Future studies could test and validate these markers as potential predictors, accounting for sample selection and bias in feature detection.

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Tools are needed to increase identification of MDD recurrence

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Cognitive control behavior and depression symptoms have been predictive of recurrence in prior studies, but with low accuracy

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In remitted Major Depressive Disorder, those who will go on to have future depressive episodes differed in cognitive control activation and connectivity

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Symptoms, performance, task activation, and seed-based connectivity can contribute to identification of risk for recurrence

Disrupted engagement of networks supporting hot and cold cognition in remitted major depressive disorder

BACKGROUND

Major depressive disorder (MDD) is characterized by dysfunction in cognitive and emotional systems. However, the neural network correlates of cognitive control (cold cognition) and emotion processing (hot cognition) during the remitted state of MDD (rMDD) remain unclear and not fully probed, which has important implications for identifying intermediate phenotypes of depression risk.

METHODS

43 young adults with rMDD and 33 healthy controls (HCs) underwent fMRI while completing separate tasks of cold cognition (Parametric Go/No-Go test) and hot cognition (Facial Emotion Processing Test). Two 2 group (rMDD, HC) × 2 event (sad/fearful faces, correct rejections) factorial models of activation were calculated in SPM8. Functional activation was evaluated in the salience and emotional network (SEN) and the cognitive control network (CCN), including hypothesized interaction between group and task within the CCN.

RESULTS

Individuals with rMDD demonstrated greater spatial extent of suprathreshold activation within the SEN during sad faces relative to HCs. There were several regions within the CCN in which HCs showed greater activation than rMDD during correct rejections of lures, whereas individuals with rMDD showed greater activation than HCs during sad or fearful faces.

LIMITATIONS

Results were not directly compared with active MDD.

CONCLUSIONS

These results provide evidence of deficient CCN engagement during cognitive control in rMDD (dysfunctional cold cognition). Elevated SEN activation during sad faces could represent heightened salience of negative emotional faces in rMDD; elevated CCN activation during emotional faces in rMDD could represent compensatory regulatory control. These group differences may represent vulnerability factors, scars of prior depressive episodes, or processes maintaining wellness.

Reliability, Convergent Validity and Time Invariance of Default Mode Network Deviations in Early Adult Major Depressive Disorder

There is substantial variability across studies of default mode network (DMN) connectivity in major depressive disorder, and reliability and time-invariance are not reported. This study evaluates whether DMN dysconnectivity in remitted depression (rMDD) is reliable over time and symptom-independent, and explores convergent relationships with cognitive features of depression. A longitudinal study was conducted with 82 young adults free of psychotropic medications (47 rMDD, 35 healthy controls) who completed clinical structured interviews, neuropsychological assessments, and 2 resting-state fMRI scans across 2 study sites. Functional connectivity analyses from bilateral posterior cingulate and anterior hippocampal formation seeds in DMN were conducted at both time points within a repeated-measures analysis of variance to compare groups and evaluate reliability of group-level connectivity findings. Eleven hyper- (from posterior cingulate) and 6 hypo- (from hippocampal formation) connectivity clusters in rMDD were obtained with moderate to adequate reliability in all but one cluster (ICC's range = 0.50 to 0.76 for 16 of 17). The significant clusters were reduced with a principle component analysis (5 components obtained) to explore these connectivity components, and were then correlated with cognitive features (rumination, cognitive control, learning and memory, and explicit emotion identification). At the exploratory level, for convergent validity, components consisting of posterior cingulate with cognitive control network hyperconnectivity in rMDD were related to cognitive control (inverse) and rumination (positive). Components consisting of anterior hippocampal formation with social emotional network and DMN hypoconnectivity were related to memory (inverse) and happy emotion identification (positive). Thus, time-invariant DMN connectivity differences exist early in the lifespan course of depression and are reliable. The nuanced results suggest a ventral within-network hypoconnectivity associated with poor memory and a dorsal cross-network hyperconnectivity linked to poorer cognitive control and elevated rumination. Study of early course remitted depression with attention to reliability and symptom independence could lead to more readily translatable clinical assessment tools for biomarkers.

Inflexibility as a Vulnerability to Depression: A Systematic Qualitative Review

The study of vulnerabilities to depression typically identifies factors that are thought to be universally maladaptive or adaptive. In contrast, researchers recently have theorized that the ability to flexibly engage in different thoughts and behaviors that fit situational demands may be most indicative of psychological health. We review empirical evidence from 147 studies reporting associations between five components of flexibility (set-shifting, affective set-shifting, cardiac vagal control, explanatory flexibility, and coping flexibility) and depression and classify studies according to strength of study design. Evidence from correlational and case-controlled studies suggests cross-sectional relationships, but few prospective studies have been conducted. We discuss limitations of existing studies, identify new directions for programmatic research, and discuss implications that flexibility has for the prevention and treatment of depression.

Attenuated intrinsic connectivity within cognitive control network among individuals with remitted depression: Temporal stability and association with negative cognitive styles

Many individuals with major depressive disorder (MDD) experience cognitive dysfunction including impaired cognitive control and negative cognitive styles. Functional connectivity magnetic resonance imaging studies of individuals with current MDD have documented altered resting-state connectivity within the default-mode network and across networks. However, no studies to date have evaluated the extent to which impaired connectivity within the cognitive control network (CCN) may be present in remitted MDD (rMDD), nor have studies examined the temporal stability of such attenuation over time. This represents a major gap in understanding stable, trait-like depression risk phenotypes. In this study, resting-state functional connectivity data were collected from 52 unmedicated young adults with rMDD and 47 demographically matched healthy controls, using three bilateral seeds in the CCN (dorsolateral prefrontal cortex, inferior parietal lobule, and dorsal anterior cingulate cortex). Mean connectivity within the entire CCN was attenuated among individuals with rMDD, was stable and reliable over time, and was most pronounced with the right dorsolateral prefrontal cortex and right inferior parietal lobule, results that were corroborated by supplemental independent component analysis. Attenuated connectivity in rMDD appeared to be specific to the CCN as opposed to representing attenuated within-network coherence in other networks (e.g., default-mode, salience). In addition, attenuated connectivity within the CCN mediated relationships between rMDD status and cognitive risk factors for depression, including ruminative brooding, pessimistic attributional style, and negative automatic thoughts. Given that these cognitive markers are known predictors of relapse, these results suggest that attenuated connectivity within the CCN could represent a biomarker for trait phenotypes of depression risk. Hum Brain Mapp 38:2939-2954, 2017. © 2017 Wiley Periodicals, Inc.

Neuroplastic Correlates in the mPFC Underlying the Impairment of Stress-Coping Ability and Cognitive Flexibility in Adult Rats Exposed to Chronic Mild Stress during Adolescence

Using a valid chronic mild stress (CMS) model of depression, we found that adolescent (postnatal days [PND] 28–41) CMS induced transient alterations in anhedonia that did not persist into adulthood after a 3-week recovery period. Previously stressed adult rats exhibited more immobility/despair behaviors in the forced swimming test and a greater number of trials to reach criterion in the set-shifting task, suggesting the impaired ability to cope with stressors and the cognitive flexibility that allows adaptation to dynamic environments during adulthood. In addition, adult rat exposure to adolescent CMS had a relatively inhibited activation in ERK signaling and downstream protein expression of phosphorylated cAMP-response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) in the medial prefrontal cortex. Further correlation analysis demonstrated that immobility and set-shifting performance were positively correlated with the inhibition of ERK signaling. These results indicated adolescent CMS can be used as an effective stressor to model an increased predisposition to adult depression.

Effects of Duloxetine Treatment on Cognitive Flexibility and BDNF Expression in the mPFC of Adult Male Mice Exposed to Social Stress during Adolescence

Early stress is a significant risk factor for the onset of mood disorders such as depression during adulthood. Impairments in cognitive flexibility mediated by prefrontal cortex (PFC) dysfunction are increasingly recognized as important etiological and pathological factors in the development of depression. Our previous study demonstrated that social defeat stress during early adolescence produced delayed deficits in cognitive flexibility in adult mice. The potential molecular mechanisms underlying these long-term consequences remain unclear. One candidate molecule is brain-derived neurotrophic factor (BDNF), which plays a vital role in neural development and synaptic plasticity. In this study, we initially examined the effects of adolescent social stress on cognitive flexibility and PFC BDNF expression within a week after the last stress exposure and 6 weeks later during adulthood. Adolescent (PND 28) male mice were subjected to stress or control manipulation for 10 days. The attentional set-shifting task (AST) was used to assess cognitive flexibility. Levels of BDNF mRNA and protein in the PFC were examined after behavioral testing. The results demonstrated that previously stressed mice exhibited delayed extra-dimensional set-shifting deficits in AST when tested as adults but not when tested as adolescents. Consistent with the cognitive alterations, adolescent stress induced dynamic alterations in BDNF expression in the medial PFC (mPFC), with a transient increase observed shortly after the stress, followed by a decrease 6 weeks later during adulthood. Next, we further determined the effects of chronic treatment with the antidepressant duloxetine during early adulthood on cognitive and molecular alterations induced by adolescent stress. Compared with the controls, duloxetine treatment reversed the cognitive deficits and increased the BDNF protein expression in the mPFC during adulthood in previously stressed mice. These findings demonstrated that BDNF expression in the mPFC was sensitive to adolescent social stress, which may contribute to the disturbance of the development and later functioning of this brain region.

Characterizing neurocognitive impairment in young people with major depression: state, trait, or scar?

BACKGROUND

Major depressive disorder (MDD) affects a quarter of adolescents and young adults and is associated with the greatest global burden of disease in this population. There is a growing literature, mostly in adults, showing that significant neurocognitive impairments are common in MDD. It remains unclear whether these impairments are pre-existing trait markers of MDD, state-related impairments that fluctuate with depressive symptoms, or 'scar' impairments that worsen with illness progression. The aim of this study is to provide a conceptual framework for understanding MDD and neurocognitive impairment in adolescence and young adulthood (ages 12-25 years).

METHOD

Examination of the evidence for neurocognitive deficits as trait, state, and scar features of MDD according to different study designs (family studies, premorbid studies, current depression, remitted depression, and longitudinal studies with repeated assessment) was conducted.

RESULTS

The few premorbid and family studies conducted in youth provide equivocal evidence for neurocognitive impairments as trait markers of MDD. The presence of state-based neurocognitive impairment remains unclear as evidence comes mostly from cross-sectional studies. There are a limited, but growing number of longitudinal studies with repeated neurocognitive assessment in youth. Studies that examined neurocognition prior to the onset of MDD and with long-term follow-up provide tentative evidence for neurocognitive scarring.

CONCLUSION

Neurocognitive impairment is a feature of MDD in adolescents and young adults. To better understand the nature, timing, and pattern of impairment, longitudinal studies that examine neurocognition before and after the development of full-threshold MDD, including following recurrence are needed. This knowledge will have important implications for mechanisms, prevention, and treatment of MDD in youth.

Cognitive Dysfunction in Major Depressive Disorder: Assessment, Impact, and Management

Cognitive dysfunction is increasingly being recognized as an important clinical dimension in major depressive disorder. This review summarizes the existing data on the epidemiology, assessment, and treatment of cognitive dysfunction among nonelderly adults with the disorder. Overall, cognitive dysfunction is prevalent, persists through periods of symptom remission, and may be independently associated with functional outcomes. However, although the evidence increasingly suggests that clinicians should be heedful of their patients' cognitive functioning, there is as yet no consensus on how best to monitor cognition clinically. In addition, although most studies have reported improved cognition with antidepressant medications, psychotherapy, and neuromodulation, the clinical significance of these improvements is unclear, and high-level evidence to guide decision making is limited. Nonetheless, given the important functional implications, clinicians should assess and monitor cognition and optimize both medication and psychological treatments to mitigate cognitive dysfunction among patients with major depressive disorder.

Differential Resting State Connectivity Patterns and Impaired Semantically Cued List Learning Test Performance in Early Course Remitted Major Depressive Disorder

OBJECTIVES

There is a well-known association between memory impairment and major depressive disorder (MDD). Additionally, recent studies are also showing resting-state functional magnetic resonance imaging (rsMRI) abnormalities in active and remitted MDD. However, no studies to date have examined both rs connectivity and memory performance in early course remitted MDD, nor the relationship between connectivity and semantically cued episodic memory.

METHODS

The rsMRI data from two 3.0 Tesla GE scanners were collected from 34 unmedicated young adults with remitted MDD (rMDD) and 23 healthy controls (HCs) between 18 and 23 years of age using bilateral seeds in the hippocampus. Participants also completed a semantically cued list-learning test, and their performance was correlated with hippocampal seed-based rsMRI. Regression models were also used to predict connectivity patterns from memory performance.

RESULTS

After correcting for sex, rMDD subjects performed worse than HCs on the total number of words recalled and recognized. rMDD demonstrated significant in-network hypoactivation between the hippocampus and multiple fronto-temporal regions, and multiple extra-network hyperconnectivities between the hippocampus and fronto-parietal regions when compared to HCs. Memory performance negatively predicted connectivity in HCs and positively predicted connectivity in rMDD. Conclusions Even when individuals with a history of MDD are no longer displaying active depressive symptoms, they continue to demonstrate worse memory performance, disruptions in hippocampal connectivity, and a differential relationship between episodic memory and hippocampal connectivity.