A preliminary profile of neuropsychological deficits associated with major depression

Impact of subjective sleep quality on objective measures of neurocognitive dysfunction in patients with major depressive disorder

Background

Sleep disturbances are prevalent in major depressive disorder (MDD). MDD and sleep disturbances are both linked to cognitive impairments. Studies exploring the mechanisms and impact of sleep disturbances on neurocognitive functioning in depressed patients are lacking and proper assessment and therapeutic interventions for sleep disturbances are not part of clinical management of MDD.

Aim

We investigated the association between subjective sleep quality and neurocognitive dysfunction in patients with MDD.

Materials and Methods

Patients with moderate MDD episode were matched and assigned to two groups with poor and good sleep quality. We used Pittsburgh Sleep Quality Index (PSQI) to assess sleep quality. To measure frontotemporally mediated cognitive functioning, following tests were administered: Wisconsin Card Sorting Test (WCST) and degraded continuous performance test (CPT-DS). Two-tailed independent samples t tests or Mann-Whitney U tests and Pearson's correlation coefficient were performed for the statistical analysis of sleep latency, sleep duration, overall sleep quality, CPT d' value, WCST correct answers, errors, and perseverative errors.

Results

Participants with MDD and poor sleep quality performed worse on cognitive tests compared to patients with MDD and good sleep quality. Scores of subjective sleep on PSQI positively correlated with WCST errors (r (60) =0.8883 P = .001) and negatively correlated with WCST correct answers (r (60) = -.869 P = .001) and measures of CPT-DS d' value (r (60) = -.9355 P = .001).

Conclusions

Poor sleep quality, notably sleep duration and sleep latency, worsens the neurocognitive impairments of MDD patients. As these impairments are found to be associated with treatment outcomes, sleep disturbances should be additionally assessed and treated in MDD episode.

Cognitive performance in depression in low- and middle-income countries: A systematic review with meta-analytic components

BACKGROUND

Depression is highly prevalent in low- and middle- income countries (LMIC) and associated with significant cognitive dysfunction across multiple domains. However, little is known about neurocognitive tests used in people with depression in LMIC. We aimed to investigate cognitive performance and cognitive tests in depression research in LMIC.

METHODS

APA PsycInfo, Embase, Ovid MEDLINE, and Global Health were systematically searched for studies that implemented a cognitive performance test in a depressed, LMIC population. Tool quality was assessed using an adapted scale for quality of measures in cross-cultural settings. Data extracted included demographics, depression and cognitive performance measures, and cognitive performance comparisons between depression and control groups.

RESULTS

29 studies met eligibility criteria, involving a total of 19,100 participants from 11 LMIC. 93.1 % of studies were conducted in upper middle-income countries. 67 cognitive performance tools were implemented. Reliability was reported for 5.6 % of cognitive performance tests and validity was reported for 8.3 %. 36.1 % of tests used were culturally adapted. 75.9 % of included studies implemented at least one memory test. Cognitive deficits were observed in all depressed groups, especially in memory (Cohen's d = -1.60, 95 % CI -2.02 to -1.18).

LIMITATIONS

Heterogeneity between studies; averaged results across memory subtypes; no assessment of depression severity and cognitive deficits associations; restrictive search terms.

CONCLUSIONS

Cognitive impairments in depression, especially in memory, are prevalent in LMIC. This research has drawn attention to the burden of cognitive dysfunction in depression in LMIC, and to the disparate research gap in LMIC. PROSPERO registration CRD42022315397.

The impact of depression on language function in individuals with Alzheimer's disease: a pre/post-treatment design

BACKGROUND

It is uncertain whether depression might affect cognitive function in Alzheimer's disease (AD). Most of studies on the effect of depression treatment on cognitive function in AD were briefly evaluated by Mini-Mental State Examination (MMSE). MMSE is poor sensitive to detect cognitive change. This study examined the cognitive response to depression treatment in AD via multi-domain assessment. In addition, we explored whether effect of depression treatment in AD is different those of late-life depression (LLD).

METHODS

This study include AD patients with depression (AD + D) and without depression (AD - D), LLD patients (LLD), and healthy controls (HC). The patients were treated according to their diagnosis for 16 weeks: acetylcholinesterase inhibitors (AChEIs) and selective serotonin reuptake inhibitors (SSRIs) for AD + D, AChEIs for AD - D, and SSRIs for LLD. The cognitive changes from pre- to post-treatment were compared between AD + D and AD - D or LLD and HC. An independent sample t test was performed to compare the degree of change between the groups. Paired t tests were used to determine cognitive function changes in each depression treatment responder group.

RESULTS

At baseline, AD + D had more impairment in language function compared to AD - D, and LLD had greater deficit in executive function than HC. After depression treatment, more impaired cognitive domains at baseline were improved in AD + D and LLD, respectively. Moreover, AD + D showed an improvement in the global cognitive function (MMSE).

CONCLUSIONS

Results indicated that language function was influenced by depression in AD, which is first evidence for specific cognitive domain related to depression in AD. Our finding indicates that depression could negatively impact cognitive function, and depression treatment may have beneficial cognitive effect in both AD and LLD. This study suggests the importance of early detection and treatment of depression in AD and LLD. Trial registration Clinical Research Information Service, CRIS, ID#: KCT0004041, Registered 5 June 2019, retrospectively registered after first patient enrollment date (4 March 2014) https://cris.nih.go.kr/cris/search/detailSearch.do?seq=14140&status=5&seq_group=14140&search_page=M .

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

BACKGROUND

Cognitive 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.

METHODS

Four 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.

RESULTS

Age 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.

LIMITATIONS

The number of HCs was relatively small, which may have slightly reduced the study's statistical power.

CONCLUSIONS

Age 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.

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.

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.

Evidence of Subjective, But Not Objective, Cognitive Deficit in New Mothers at 1-Year Postpartum

Background: The experience and even existence of cognitive deficits in the postpartum period is uncertain, with only a few scientific studies, reporting inconsistent results. Methods: In this study, we investigate cognition in 86 women (43 first-time mothers 1 year postpartum and 43 non-mothers). Results: Mothers and non-mothers showed no significant differences on measures of objective cognition (verbal memory, working memory, and processing speed or theory of mind). Despite the absence of objective differences, mothers self-reported significantly worse subjective memory than non-mothers. To interpret the difference between objective and subjective measures of memory, we investigated relationships between subjective memory, objective memory, and wellbeing. Mothers, but not non-mothers, showed a positive correlation between subjective and objective measures of memory, indicating mothers are "in-tune" with their memory performance. Mothers also demonstrated a positive relationship between subjective memory and wellbeing (sleep, anxiety, and depression), where better wellbeing correlated with higher subjective memory. This relationship was not apparent in non-mothers. The results suggest that poorer sleep, higher anxiety, and higher depression are related to reports of poorer self-reported memory in mothers. Conclusion: Our results add to our growing understanding of maternal cognition at 1 year postpartum, with no evidence of cognitive differences between mothers and non-mothers.

Auditory event-related potentials in separating patients with depressive disorders and non-depressed controls: A narrative review

This narrative review brings together the findings regarding the differences in the auditory event-related potentials (ERPs) between patients with depressive disorder and non-depressed control subjects. These studies' results can inform us of the possible alterations in sensory-cognitive processing in depressive disorders and the potential of using these ERPs in clinical applications. Auditory P3, mismatch negativity (MMN) and loudness dependence of auditory evoked potentials (LDAEP) were the subjects of the investigation. A search in PubMed yielded 84 studies. The findings of the reviewed studies were not highly consistent, but some patterns could be identified. For auditory P3b, the common findings were attenuated amplitude and prolonged latency among depressed patients. Regarding auditory MMN, especially the amplitude of duration deviance MMN was commonly attenuated, and the amplitude of frequency deviance MMN was increased in depressed patients. In LDAEP studies, generally, no differences between depressed patients and non-depressed controls were reported, although some group differences concerning specific depression subtypes were found. This review posits that future research should investigate whether certain stimulus conditions are particularly efficient at separating depressed and non-depressed participant groups. Future studies should contrast responses in different subpopulations of depressed patients, as well as different clinical groups (e.g., depressive disorder and anxiety disorder patients), to investigate the specificity of the auditory ERP alterations for depressive disorders.

Cognitive dysfunction and white matter hyperintensities in Fabry disease

Fabry disease (FD) is an X-linked lysosomal storage disorder with multi-system involvement including cerebrovascular disease. Patients with FD also have a high risk of ischaemic stroke and TIA. White matter hyperintensities are common, but their clinical impact on cognition remains uncertain. Previous studies have examined the neuropsychological profile of FD, but have been inconclusive in part due to methodological limitations including small sample sizes. We sought to address these limitations in a case-control study of 26 patients with Fabry disease with mild to moderate disease symptoms matched with 18 healthy controls for age and premorbid intellectual level. We obtained detailed neuropsychological data and MRI neuroimaging data on the severity of white matter changes. Mood was accounted for as a possible confounder. Our results showed significant compromise of executive functions and information processing speed for the FD group. Error analyses suggested that the compromise of executive functions could not be entirely accounted for by slowed information processing speed. We demonstrated significant correlations between cognitive decline and the overall volume of white matter hyperintensities in the FD group. Our results point to significant compromise of cognition in FD even without stroke or mood difficulties. This suggests that neuropsychological assessment and rehabilitation should be routinely offered to patients with FD.

Preliminary Support for a Cognitive Remediation Intervention for Women During the Menopausal Transition: A Pilot Study

Background: Menopause is associated with physical and emotional symptoms, and subjective cognitive concerns that are generally not borne out on objective cognitive measures. This discrepancy suggests that a psychological rather than biological mechanism likely mediates the cognitive concerns of women in menopause. The current study assessed the feasibility and effectiveness of a cognitive remediation intervention with the goal of reducing subjective perceptions of cognitive difficulty during the menopause. Methods: Twenty-seven menopausal women (M age = 53.74, SD = 4.14) completed a 5-week group-based intervention (with a post-group booster) consisting of 2-h weekly sessions. Participants completed pre- and post-intervention measures capturing subjective cognitive ability, mood, anxiety, stress, personality, and objective cognitive tests. The primary variable of interest was self-reported cognitive confidence measured by the Memory and Cognitive Confidence Scale (MACCS). Results: All but one MACCS subscale significantly decreased over the course of treatment (with lower scores associated with higher confidence) and effect sizes ranged from small to large (d = -0.39 to -0.91) with gains maintained at 1-month follow-up. Interestingly, no change in objective cognitive test performance was observed, indicating increases in subjective cognitive confidence in the absence of objective cognitive improvement. There was no change in mood, anxiety, or stress scores. Two-level HLM analyses revealed that those with higher baseline neuroticism, as measured by the NEO Personality Inventory, had smaller decreases in post-group MACCS High Standards subscale relative to those with lower baseline neuroticism (p = 0.027, d = -0.45). Those with higher baseline depression scores on the Depression Anxiety Stress Scale (DASS-21) had a smaller decrease in post-intervention MACCS Total Score relative to those with lower depression ratings. Conclusion: To our knowledge, this is the first feasibility study of its kind targeting perceptions of cognitive impairment during menopause. Although generally well-tolerated, recruitment and scheduling difficulties were flagged as challenges to engagement while a small sample size and lack of control group limit conclusions about efficacy. Providing current results could be replicated with enhanced methods, these results provide support that cognitive remediation is a feasible and credible treatment, and may improve quality of life for women in menopause. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT03311880.

Anomalous functional connectivity within the default-mode network in treatment-naive patients possessing first-episode major depressive disorder

BACKGROUND AND OBJECTIVE

Previous studies have shown that the default-mode network (DMN) has a substantial role in patients with major depressive disorder (MDD). However, there is a shortage of information regarding variations in the functional connectivity (FC) of the DMN of treatment-naive patients with first-episode MDD. The present study aims to explore the FC of the DMN in such patients.

METHODS

The study population consisted of 33 patients and 35 controls, paired regarding age, gender, education level, and health condition. Depression severity was assessed through the Hamilton Depression Scale (HAM-D), and subjects underwent evaluation during the resting-state through functional magnetic resonance imaging (rs-fMRI). To assess the result, we used FC and ICA. We used Spearman's correlation test to detect potential correlations between anomalous FC and severity of HAM-D scores.

RESULTS

We have found a decreased FC in the left medial orbitofrontal gyrus (MOFG) and right marginal gyrus (SMG) in depressive patients compared to controls. There was a negative correlation between abnormal FC in the right SMG and HAM-D scores. We have not found any increase in FC of the DMN in treatment-naive, first-episode of MDD patients.

CONCLUSIONS

Our study provided evidence of a negative correlation between abnormal FC in the DMN and severity of depression symptoms measured by HAM-D in treatment-naive MDD patients. This finding could shed some light on the relevance of DMN for understanding the pathophysiology of cognitive impairment in MDD.

Investigating whether depressed youth exhibiting elevated C reactive protein perform worse on measures of executive functioning, verbal fluency and episodic memory in a large, population based sample of Dutch adolescents

Cognitive functioning is disrupted during a depressive episode and cognitive dysfunction persists when depression is in remission. A subtype of depressed individuals who exhibit elevated inflammatory biomarkers may be at particular risk for cognitive dysfunction. We examined whether an elevated inflammatory biomarker (C-reactive protein: CRP) in acute and/or remitted depression was associated with specific deficits in executive functioning, episodic memory, and verbal fluency. Data were drawn from a population-based sample of Dutch adolescents (N = 1066; 46% male) recruited at the age of 11 and followed over the course of eight years. We tested whether adolescents with either, (i) a history of depression (Wave 1-3) or (ii) current depression (Wave 4), and elevated levels of C-reactive protein measured in blood at Wave 3 performed worse on cognitive assessments at Wave 4. Eight measures of cognitive functioning were hypothesized to load on to one of three dimensions of cognitive functioning (executive functioning, episodic memory, and verbal fluency) within a structural equation model framework. Higher levels of CRP were associated with worse future executive functioning in adolescents with and without current/prior depression. A current depression diagnosis also was associated with worse executive functioning. There was consistent evidence linking low socioeconomic status and health-related covariates (high body mass index/sedentary behavior) with worse performance across multiple measures of cognitive functioning and, importantly, the association of depression/CRP and executive functioning was no longer significant when controlling for these covariates. Future studies may benefit from investigating whether specific depressogenic behaviors (e.g., sedentary behavior/substance use) mediate a relationship between depression and worse executive functioning, potentially via a prospective pathway through elevated inflammation.

Differential neural structures, intrinsic functional connectivity, and episodic memory in subjective cognitive decline and healthy controls

The neural correlates of subjective cognitive decline (SCD; i.e., without objectifiable deficit) remain to be elucidated. Possible causes of SCD include early neurodegeneration related to Alzheimer's disease or functional and structural changes related to sub-clinical depression. We investigated the relationship between episodic memory performance or memory complaints and structural or functional magnetic resonance imaging (MRI) measures in participants with SCD (n=18) but without psychiatric disorders and healthy controls (n=31). In SCD, memory complaints were not associated with memory performance but with sub-clinical depression and executive functions. SCD-associated memory complaints correlated with higher amygdala and parahippocampal gyrus (specifically subiculum) gray matter density. In controls, but not in SCD, mesiotemporal gray matter density and superior frontal gyrus functional connectivity predicted memory performance. In contrast, in SCD, only a trend toward a correlation between memory performance and gray matter density in the parietooccipital lobes was observed. In our memory-clinic sample of SCD, we did not observe incipient neurodegeneration (limited to structural and functional MRI) but rather sub-clinical depression underlying subjective cognitive complaints.

Misplacement of something inside the refrigerator is not a sign of dementia, but a probable symptom of attention deficit due to depression

The objective of this study is to investigate the clinical significance of a specific behavior of misplacing items in a refrigerator (i.e., placing extremely unusual things such as remote control and/or cellular phone in a refrigerator) as a symptom of cognitive dysfunction. Patients with memory complaints were asked whether they ever experienced misplacing items in a refrigerator, such as placing a remote control, a cellular phone, or other extremely unusual things inside a refrigerator (referred to as the ‘fridge sign’). Among the 2172 individuals with memory complaints, 55 (2.5%) experienced symptoms of the ‘fridge sign’. We investigated the cognitive profiles of ‘fridge sign’-positive patients and performed follow-up evaluations with neuropsychological tests or telephone interviews. The ‘fridge sign’ was mostly found in individuals diagnosed as subjective cognitive decline (n = 33, 60%) or mild cognitive impairment (MCI, n = 20, 36.4%) with depressive mood and was relatively rare in dementia states (n = 2, 3.5%). Moreover, none of the ‘fridge sign’-positive patients showed significant cognitive decline over the follow-up period. We compared the cognitive profiles and the clinical progression of 20 ‘fridge sign’-positive MCI patients and 40 ‘fridge sign’-negative MCI patients. ‘Fridge sign’-positive MCI patients had worse scores on the Stroop test color reading and had higher scores on the geriatric depression scale than ‘fridge sign’-negative MCI patients, which indicates that the ‘fridge sign’ could be indicative of selective attention deficit in patients with depression rather than indicative of cognitive decline related to dementia.

A Systematic Review of Executive Function and Information Processing Speed in Major Depression Disorder

Background: Major depression is a psychiatric disorder characterized neuropsychologically by poor performance in tasks of memory, attention, processing speed, and executive function. The aim of this systematic review was to examine the evidence regarding the neuropsychological profile of people with major depression and to determine which of two explanatory models—the processing speed hypothesis or the cognitive effort hypothesis—has most empirical support. Methods: We searched three relevant databases and reviewed the reference lists of the articles retrieved. The results obtained with the Trail Making Test and the Stroop Color-Word Test were reviewed for 37 studies published between 1993 and 2020. Results: The empirical evidence supports both hypotheses: cognitive effort and processing speed, suggesting that depression is not only characterized by psychomotor slowing but also involves a specific deficit in executive function. Discussion: We discuss potentially relevant variables that should be considered in future research in order to improve knowledge about the neurocognitive profile of depression. The main limitation of this study derives from the considerable heterogeneity of participants with MD, which makes it difficult to compare and integrate the data.

Cognitive mechanisms underlying depressive disorders in ADHD: A systematic review

The risk for major depressive disorder (MDD) is considerably increased in young adults with attention-deficit/hyperactivity disorder (ADHD) but underlying mechanisms are poorly understood. This review explores ADHD-specific neurocognitive impairments as possible underlying mechanisms for ADHD-depression comorbidity. Two systematic literature searches were conducted in EBSCOhost, PubMED, and Cochrane Reviews databases according to PRISMA guidelines. The first search identified 18 meta-analyses of cross-sectional and longitudinal studies on cognitive dysfunctions in MDD across the lifespan. The second search identified six original studies on reaction time variability in MDD. During acute depression, children and adults showed cognitive deficits that overlapped with some of the ADHD-related impairments. Findings from remitted patients, high-risk individuals, and few prospective studies suggest that a subset of these shared impairments, specifically executive dysfunctions (selective attention, verbal fluency, working memory) and long-term memory problems, are candidate pre-existing risk markers of depression. We discuss if and how these specific neurocognitive mechanisms may mediate developmental pathways from ADHD to depression. If replicated by longitudinal studies, these findings may guide future prevention strategies.

Cognitive remediation therapy for partially remitted unipolar depression: A single-blind randomized controlled trial

BACKGROUND

There is an urgent need for the development and evaluation of targeted interventions for cognitive impairment (CI) in patients with (partially) remitted major depressive disorder (MDD). The aim of our study was therefore to evaluate the effect of cognitive remediation therapy (CRT) on cognitive and psychosocial functioning in a sample of patients with MDD, taking into account comorbidity, psychopathology, remission status and CI profile. Furthermore, we compared a generalized training (GT) with an individualized training (IT) approach regarding their effects on cognition.

METHODS

Sixty-two MDD patients in partial remission with CI were randomly assigned to a control group (CG), IT or GT. Participants of GT trained six cognitive subdomains (divided attention, selective attention, alertness, working memory, planning and response inhibition), whereas participants of IT trained their three most deficient cognitive subdomains as identified at baseline. Participants of both intervention groups trained three times per week over a five-week period. Both training groups received additional 30-minute compensatory-transfer sessions once per week.

RESULTS

Attention appeared to be the most frequently impaired cognitive domain as well as the domain which was significantly improved by CRT, with medium to large effect sizes. No difference in improvement was found between IT and GT. The analyses also revealed greater improvement in self-assessed psychosocial functioning in training participants (GT and IT combined) compared to the CG.

LIMITATIONS

Due to the small sample size, the present results are preliminary in nature.

CONCLUSION

CRT was well accepted, and patients transferred the attentional improvement to real life, as measured by self-assessed psychosocial functioning. IT yielded no additional advantages over GT. We propose CRT as an integral part of the treatment plan for patients with depression suffering from CI.

The Effect of Transcutaneous Auricular Vagal Nerve Stimulation (taVNS) on P3 Event-Related Potentials during a Bayesian Oddball Task

Transcutaneous auricular Vagal Nerve Stimulation (taVNS) is a non-invasive brain stimulation technique associated with possible modulation of norepinephrinergic (NE) activity. NE is suspected to contribute to generation of the P3 event-related potential. Recent evidence has produced equivocal evidence whether taVNS influences the P3 in healthy individuals during oddball tasks. We examined the effect of taVNS on P3 amplitudes using a novel visual Bayesian oddball task, which presented 200 sequences of three stimuli. The three consecutive stimuli in each sequence are labelled Draw 1, Draw 2 and Draw 3. In total, 47 Subjects completed this visual Bayesian oddball task under randomised sham and active taVNS stimulation in parallel with an electroencephalographic (EEG) recording. We conducted exploratory analyses of the effect of taVNS on P3 amplitudes separately for Draws. We found typical oddball effects on P3 amplitudes at Draws 1 and 2, but not Draw 3. At Draw 2, the oddball effect was enhanced during active compared to sham taVNS stimulation. These data provide evidence that taVNS influences parietal P3 amplitudes under specific circumstances. Only P3 amplitudes at Draw 2 were affected, which may relate to closure of Bayesian inference after Draw 2. Our findings seemingly support previously reported links between taVNS and the NE system.

Altered Resting-State Functional Connectivity of Multiple Networks and Disrupted Correlation With Executive Function in Major Depressive Disorder

Background: Major depressive disorder (MDD) is one of the most common and costly psychiatric disorders. In addition to significant changes in mood, MDD patients face an increased risk of developing cognitive dysfunction. It is important to gain an improved understanding of cognitive impairments and find a biomarker for cognitive impairment diagnosis in MDD.

Methods: One hundred MDD patients and 100 normal controls (NCs) completed resting-state fMRI (rs-fMRI) scan, in which 34 MDD patients and 34 NCs had scores in multiple cognitive domains (executive function, verbal fluency, and processing speed). Twenty-seven regions of interest from the default mode network (DMN), central executive network (CEN), salience network (SN), and limbic system (LS) were selected as seeds for functional connectivity (FC) analyses with the voxels in the whole brain. Finally, partial correlations were conducted for cognitive domain scores and FCs with significant differences between the MDD and NC groups.

Results: Significant FC differences between groups were identified among the seeds and clusters in the DMN, CEN, LS, visual network, somatomotor network, ventral attention network, and dorsal attention network. In the MDD patients, the magnitude of the Stroop interference effect was positively correlated with the illness duration, and the illness duration was negatively correlated with the FC between the right ventral hippocampal gyrus and the left inferior frontal gyrus. However, the correlation between the Stroop interference effect and the FC of the right anterior prefrontal cortex with the left cerebellum_4_5 was disrupted in these patients.

Conclusions: The MDD patients have altered FCs among multiple brain networks and a disrupted correlation between the FC of prefrontal cortex and executive function. The disrupted correlation could present before the symptoms develop and may be the core process in the development of executive function impairment.

Resilience as a multimodal dynamic process

AIM

Resilience is rapidly gaining momentum in mental health literature. It provides a new understanding of the highly variable trajectories of mental illness, and has consistently been linked with improved mental health outcomes. The present review aims to clarify the definition of resilience and to discuss new directions for the field.

METHODS

After discussing the definition of resilience, this narrative review synthesizes evidence that identifies the specific protective factors involved in this process. This review also addresses the mechanisms that underlie resilience.

RESULTS

Recent literature has clarified the three core components of resilience, which are the presence of an adversity or specific risk for mental illness; the influence of protective factors that supersede this risk; and finally, a subsequently more positive outcome than expected. Now that these are largely agreed upon, the field should move on to addressing other topics. Resilience is a dynamic process by which individuals utilize protective factors and resources to their benefit. It can vary within one individual across time and circumstance. It can also refer to good functional outcomes in the context of diagnosable illness. While previous research has focused on psychological resilience, it is essential that resilience is conceptualized across modalities.

CONCLUSIONS

The field should move towards the development of a multimodal model of resilience. Researchers should now focus on producing empirical research which clarifies the specific protective factors and mechanisms of the process, aligning with the core concepts of resilience. This growing, more homogeneous evidence base, can then inform new intervention strategies.

Characterizing neurocognitive markers of familial risk for depression using multi-modal imaging, behavioral and self-report measures

BACKGROUND

Major depressive disorder (MDD) is associated with poorer behavioral performance in domains of working memory and associated cognitive systems for cognitive control and attention. Functional neuroimaging studies show altered functioning in MDD in frontal executive control circuits implicated in these cognitive processes. It is not yet known whether poor cognitive performance involving these circuits is part of the familial risk for MDD, and we addressed this issue using a multi-modal imaging, behavioral and self-report approach in unaffected first-degree relatives of parent probands with MDD.

METHODS

72 unaffected adult first-degree relatives of probands with MDD (mean age 30.5 ± 13.4 years) with and 66 case-wise matched non-relative controls underwent functional magnetic resonance imaging during performance of 'n-back' working memory task, a Go/No-go task assessing cognitive control and an Auditory Oddball test of selective attention. Groups were compared on imaging data analyzed voxel wise with a focus on dorsolateral prefrontal cortex, anterior cingulate cortex and insula regions of interest, and on corresponding behavioral accuracy and reaction time data. Symptoms were assessed using self-report scales.

RESULTS

Relatives were distinguished by comparatively decreased activation in the left dorsolateral prefrontal cortex (DLPFC) during updating of working memory. Behaviorally, relatives also showed more errors of omission during working memory updating. DLPFC hypo-activation was associated with greater depressive symptom severity.

CONCLUSIONS

Deficits in cognitive processing may be part of the profile of familial risk for depression, preceding illness onset, specifically in the domain of working memory.

Assessment in Work Productivity and the Relationship with Cognitive Symptoms (AtWoRC): primary analysis from a Canadian open-label study of vortioxetine in patients with major depressive disorder (MDD)

OBJECTIVE

The Assessment in Work Productivity and the Relationship with Cognitive Symptoms (AtWoRC) study aimed to assess the association between cognitive symptoms and work productivity in gainfully employed patients receiving vortioxetine for a major depressive episode (MDE).

METHODS

Patients diagnosed with major depressive disorder (MDD) and treated with vortioxetine independently of study enrollment were assessed over 52 weeks at visits that emulated a real-life setting. Patients were classified as those receiving vortioxetine as the first treatment for their current MDE (first treatment) or having shown inadequate response to a previous antidepressant (switch). The primary endpoint was the correlation between changes in patient-reported cognitive symptoms (20-item Perceived Deficits Questionnaire [PDQ-D-20]) and changes in work productivity loss (Work Limitations Questionnaire [WLQ]) at week 12. Additional assessments included changes in symptom and disease severity, cognitive performance, functioning, work loss, and safety.

RESULTS

In the week 12 primary analysis, 196 eligible patients at 26 Canadian sites were enrolled, received at least one treatment dose, and attended at least one postbaseline study visit. This analysis demonstrated a significant, strong correlation between PDQ-D-20 and WLQ productivity loss scores (r=0.634; p<0.001), and this correlation was significant in both first treatment and switch patients (p<0.001). A weaker correlation between Digit Symbol Substitution Test and WLQ scores was found (r=-0.244; p=0.003).

CONCLUSION

At 12 weeks, improvements in cognitive dysfunction were significantly associated with improvements in workplace productivity in patients with MDD, suggesting a role for vortioxetine in functional recovery in MDD.

Cognitive effects of non-surgical brain stimulation for major depressive disorder: protocol for a systematic review and meta-analysis

INTRODUCTION

Non-surgical brain stimulation techniques may be considered as alternative or add-on treatments for patients with major depressive disorder who failed to respond to pharmacological interventions. Electroconvulsive therapy has been shown to be highly effective in reducing depressive symptoms but stakeholders remain concerned about adverse cognitive effects. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation may be associated with more benign adverse effect profiles and may indeed improve certain cognitive functions such as memory and attention. To guide clinical decision-making, we will carry out a systematic review and meta-analysis of the cognitive effects of eight non-surgical brain stimulation techniques.

METHODS AND ANALYSIS

A systematic literature search of the Embase, PubMed/MEDLINE and PsycINFO databases, the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov and OpenGrey will be performed. We will include both randomised clinical trials which report on at least one cognitive measure post treatment as well as non-randomised trials and pre-post intervention studies. There are no restrictions to the type of cognitive outcome measures, except that the tests are standardised and psychometrically validated. The Revised Cochrane tool for assessing risk of bias in randomised trials (RoB 2.0) will be used to evaluate included trials. Pre-post studies will be evaluated using the quality assessment tool developed by the US National Heart, Lung and Blood Institute. Meta-analysis, meta-regression, subgroup and sensitivity analyses will be conducted where sufficient data are available.

ETHICS AND DISSEMINATION

No ethical approval is needed to conduct this work. The findings will be submitted for publication in peer-reviewed journals and presented at scientific meetings.

PROSPERO REGISTRATION NUMBER

CRD42018118850.

Emotion regulation mediates the relationship between verbal learning and internalizing, trauma-related and externalizing symptoms among early-onset, persistently delinquent adolescents

Research supports cascading relationships among internalizing and externalizing symptoms, and academic problems. This constellation of problems characterizes Early-Onset/Persistent Delinquent [EOPD] youth and appropriately targeted interventions accounting for this comorbidity may improve outcomes. To investigate these relationships in EOPD youth, we characterized their cross-diagnostic psychopathology and verbal (word-list) learning/memory and evaluated: 1) verbal learning/memory profiles of Withdrawn/Depressed relative to Non-Withdrawn/Depressed youth; 2) cognitive and psychiatric predictors of verbal learning; and 3) emotion regulation as a mediator of psychiatric and cognitive relationships. Results indicated Withdrawn/Depressed youth recalled significantly fewer words during immediate, and some delayed, recall conditions. Less word-learning was predicted by: Withdrawn/Depressed classification, higher trauma-specific re-experiencing symptoms, greater emotion dysregulation, weaker executive skills, fewer trauma-avoidance and aggressive symptoms, and earlier alcohol-use onset. Emotion regulation strongly mediated the relationship between verbal learning and psychopathology, but not cognitive skills, among youth at high-risk for school dropout. Mental health and education implications are discussed.

Gamified Cognitive Control Training for Remitted Depressed Individuals: User Requirements Analysis

BACKGROUND

The high incidence and relapse rates of major depressive disorder demand novel treatment options. Standard treatments (psychotherapy, medication) usually do not target cognitive control impairments, although these seem to play a crucial role in achieving stable remission. The urgent need for treatment combined with poor availability of adequate psychological interventions has instigated a shift toward internet interventions. Numerous computerized programs have been developed that can be presented online and offline. However, their uptake and adherence are oftentimes low.

OBJECTIVE

The aim of this study was to perform a user requirements analysis for an internet-based training targeting cognitive control. This training focuses on ameliorating cognitive control impairments, as these are still present during remission and can be a risk factor for relapse. To facilitate uptake of and adherence to this intervention, a qualitative user requirements analysis was conducted to map mandatory and desirable requirements.

METHODS

We conducted a user requirements analysis through a focus group with 5 remitted depressed individuals and individual interviews with 6 mental health care professionals. All qualitative data were transcribed and examined using a thematic analytic approach.

RESULTS

Results showed mandatory requirements for the remitted sample in terms of training configuration, technological and personal factors, and desirable requirements regarding knowledge and enjoyment. Furthermore, knowledge and therapeutic benefits were key requirements for therapists.

CONCLUSIONS

The identified requirements provide useful information to be integrated in interventions targeting cognitive control in depression.

Emotional working memory in patients with major depressive disorder

Objective

This study was performed to examine the working memory (WM) encoding and retrieval abilities in patients with major depressive disorder (MDD) and determine whether a mood-congruent memory effect is present.

Methods

The modified Sternberg WM paradigm with positive, negative, and neutral emotional pictures was used to investigate the WM abilities of 26 patients with MDD and 26 healthy controls (HCs).

Results

No significant difference in picture WM was found between the MDD and HC groups; however, the accuracy of picture position WM was significantly lower and the response time was significantly longer in the MDD than HC group, regardless of the picture or position WM. Additionally, in the MDD group, the accuracy of negative picture/position WM was significantly higher than that of positive picture/position WM.

Conclusions

These results suggest that in patients with MDD, spatial WM impairment was more severe than object WM. In addition, these patients’ WM retrieval was impaired, resulting in a decrease in WM retrieval ability, which may be an important cause of the slow thought in patients with MDD. Moreover, patients with depression have a mood-congruent memory effect, which may be an important factor in the occurrence and maintenance of depression.

Transcranial direct current stimulation of 20- and 30-minutes combined with sertraline for the treatment of depression

BACKGROUND

Transcranial direct current stimulation (tDCS) can be an effective treatment for depression, however, the duration of the stimulation session, among other parameters, needs to be optimized.

METHODS

69 mild to moderately depressed patients (age 37.6±10.5years, 19 men) were randomized into three groups - 30-, 20-minute or sham tDCS. 10 daily sessions of anodal/sham tDCS of the left DLPFC (0.5mA; electrode 3,5×7cm) combined with 50mg/day of sertraline were performed. Mood, cognition and BDNF level were assessed before and after the treatment.

RESULTS

A significant difference between groups was observed in the percent change of the Hamilton Depression Rating Scale (F(2, 66)=10.1; p<0.001). Sham group (43.4%±18.1) had a smaller improvement compared to the 30-minute (63.8%±13.4; 95% CI: 11.23-29.44; p=0.00003) and 20-minute group (53.2%±15.3; 95% CI: 0.21-19.26; p=0.045). 30-minute group had significantly greater percent improvement than 20-minute group (95% CI: 1.74-19.46; p=0.02). Responders constituted 89%, 68%, and 50% and remitters - 70%, 27%, and 35% in the 30-, 20-minute and sham groups, respectively. A significant difference in the number of responders was observed between 30-minute vs. sham group (odds ratio=8; 95% CI, 2.59-24.69; p=0.001), in remission rate - between 30-minute vs. sham (odds ratio=4.40; 95% CI, 2.02-9.57; p=0.02) and vs. 20-minute (odds ratio=6.33; 95% CI, 2.85-14.10; p=0.003) groups. Two hypomania cases and one case of blood pressure elevation were detected in the 20-minute group. Among neuropsychological tests, only the change in Digit Span Backwards test showed a significant interaction between groups (TIME*GROUP; F(2, 65)=6,6, p=0.002); a greater improvement was observed in both active groups compared to sham (p<0.05). The change in BDNF level after the treatment did not show the significant difference between groups.

CONCLUSIONS

tDCS of 20- or 30-minutes combined with sertraline are efficient for the treatment of mild and moderate depression; the effect of 30min stimulation exceeds the one obtained from 20min.

Neural systems underlying affective disorders

Three main approaches are used to explore the neural correlates of mood disorder: neuropsychological studies, neuroimaging studies and post-mortem investigations. Lesion studies implicate disturbances in the frontal lobe, basal ganglia, striatum and anterior temporal cortex. Early neurocognitive and neuropathological investigations led to a ‘hypofrontality’ hypothesis of unipolar and bipolar depression, but functional neuroimaging has revealed a more complex picture. Thus, increased metabolism may occur in the subgenual anterior cingulate gyrus in resting-state studies of depression and sad-mood induction. Antidepressants may reduce this activity. Amygdala hyperactivation also is associated with affective disorders. Task-related studies reveal abnormal biases in memory, the experience of pleasure and the perception of emotional facial expressions. There is still little clarity whether the abnormalities in brain activation represent state or trait characteristics of affective disorders.

Evaluation of the benefits of exercise on cognition in major depressive disorder

BACKGROUND

Cognitive impairment is increasingly recognized as a significant symptom in patients with major depressive disorder (MDD). While exercise is already recommended in many treatment guidelines for patients with MDD and has been shown to improve cognition in other disorders (e.g., Alzheimer's, Parkinson's, schizophrenia), limited research is available evaluating the effect of exercise on cognition in MDD.

METHODS

We provide a narrative review of existing literature regarding the effect(s) of exercise on cognition across several neurodegenerative and psychiatric diseases, and particularly in MDD, with specific emphasis on study design and methodology that may impair adequate synthesis of the results. We also describe mechanisms by which exercise may improve cognition in depression and other brain disorders.

RESULTS

Of existing studies with MDD, data are equivocal, as some are supportive of improved cognition, whereas others demonstrate no benefit. Several limitations were noted, including insufficiently-powered designs, variability in interventions examined (e.g., aerobic, anaerobic, mind-body) or control groups, lack of attention to the status of baseline cognitive impairment, and/or heterogeneity across outcome measures and clinical characteristics.

CONCLUSIONS

While preliminary results suggest the potential for exercise as a beneficial treatment or augmentation strategy for impaired cognition in MDD, the aforementioned limitations necessitate further investigation.

White matter correlates of impaired attention control in major depressive disorder and healthy volunteers

BACKGROUND

Major depressive disorder (MDD) is associated with impaired attention control and alterations in frontal-subcortical connectivity. We hypothesized that attention control as assessed by Stroop task interference depends on white matter integrity in fronto-cingulate regions and assessed this relationship using diffusion tensor imaging (DTI) in MDD and healthy volunteers (HV).

METHODS

DTI images and Stroop task were acquired in 29 unmedicated MDD patients and 16 HVs, aged 18-65 years. The relationship between Stroop interference and fractional anisotropy (FA) was examined using region-of-interest (ROI) and tract-based spatial statistics (TBSS) analyses.

RESULTS

ROI analysis revealed that Stroop interference correlated positively with FA in left caudal anterior cingulate cortex (cACC) in HVs (r = 0.62, p = 0.01), but not in MDD (r = -0.05, p= 0.79) even after controlling for depression severity. The left cACC was among 4 ROIs in fronto-cingulate network where FA was lower in MDD relative to HVs (F_(1,41) = 8.87, p = 0.005). Additionally, TBSS showed the same group interaction of differences and correlations, although only at a statistical trend level.

LIMITATIONS

The modest sample size limits the generalizability of the findings.

CONCLUSIONS

Structural connectivity of white matter network of cACC correlated with magnitude of Stroop interference in HVs, but not MDD. The cACC-frontal network, sub-serving attention control, may be disrupted in MDD. Less cognitive control may include enhanced effects of salience in HVs, or less effective response inhibition in MDD. Further studies of salience and inhibition components of executive function may better elucidate the relationship between brain white matter changes and executive dysfunction in MDD.

The Relationships among Tryptophan, Kynurenine, Indoleamine 2,3-Dioxygenase, Depression, and Neuropsychological Performance

It has been suggested that the metabolic enzyme indoleamine 2,3-dioxygenase (IDO) is a biological mediator of inflammation related to the psychopathology of depression, with a Kynurenine (KYN) increase in the Tryptophan (TRP) metabolic pathway, resulting in reduced Serotonin. In this study, we examined KYN, TRP, and the ratio of KYN to TRP concentrations × 10³ (KT Ratio) in serum and cerebrospinal fluid (CSF) in (a) a group of depressed patients and (b) a control group of patients referred to a neurologic outpatient clinic for whom no specific diagnosis could be established. The KT Ratio is considered an index that represents IDO. The participants were examined with the Beck Depression Inventory II (BDI-II), the Montgomery Aasberg Depression Rating Scale (MADRS), and a neuropsychological test battery. We found no significant differences between the two study groups with respect to TRP, KYN, or KT Ratio in serum or CSF. Differences in neuropsychological performance between the two patient groups could be seen in the following tests: Animal Fluency, Digit Symbol, the DKEFS Color-Interference Test (Naming Part), Trail Making Test A and B, and the Grooved Pegboard Non-dominant Hand. KYN in serum correlated highly with KYN in CSF. KYN in serum correlated significantly with both age and gender. When analyzing males and females separately, we found that women had a lower level of TRP in both serum (Mann-Whitney U-test: TRP in Serum; p = 0.001) and CSF (Mann-Whitney U-test: TRP in CSF; p = 0.003). Women had a lower level of KYN in serum (p = 0.029) than men did. Age was positively associated with KYN. KYN in CSF correlated only with age, however; there were no gender differences. No significant relationship was seen between BDI-II and MADRS on the one hand, and KYN and TRP on the other. KYN in CSF as the KT Ratio in both serum and CSF was associated with neuropsychological performance. Thus, we suggest that KYN and KT Ratio are related more strongly to neuropsychological performance than to affective symptoms in depression.

Neuropsychological Assessment in Multiple Sclerosis

Abstract. Neuropsychological deficits in multiple sclerosis (MS) are common. Over the past decades, many different procedures have been employed in diagnosing these deficits. Even though certain aspects of cognitive performance such as information processing speed and working memory may be affected more frequently than other cognitive functions, no specific deficit profile has been established in MS. This article provides an overview of the neuropsychological diagnostic procedures in MS and allows the reader to reach an informed decision on the applicability of specific procedures and the availability of study data in the context of MS. Additionally, it makes recommendations on the compilation of both screening procedures and extensive test batteries.

Childhood adversity and cognitive functioning in patients with major depression

OBJECTIVE

Major depression is often accompanied by deficits in cognitive functioning and lowered executive functions. However, not all depressed patients show impairments in these domains. The aim of this study was to examine whether different kinds of childhood adversity might account for cognitive deficits in patients with major depression.

METHODS

Ninety-one patients with major depression (DSM-IV) and 40 healthy controls completed a neuropsychological test battery assessing memory, processing speed and executive functions. The Childhood Trauma Questionnaire (CTQ) was used to measure the severity and number of incidences of sexual, physical and emotional abuse and physical and emotional neglect.

RESULTS

Patients with major depression had a significantly higher number of traumas and reported more severe emotional abuse, emotional neglect and physical neglect than healthy controls. Patients performed less well in memory tasks, general knowledge and processing speed than healthy controls. Hierarchical regression analyses indicated that the overall number of traumas was significantly associated with poorer general knowledge, lower processing speed and impaired executive functions in patients with major depression. A second model including all CTQ-subscales simultaneously demonstrated an association between physical neglect and poorer verbal learning, and physical abuse and diminished executive functions.

CONCLUSION

A higher number of childhood adversities may influence general knowledge, processing speed and executive functions in patients with major depression. In addition, physical abuse and neglect seemed to be associated with verbal learning deficits and poorer executive functions.

Impact of deep brain stimulation of the ventral anterior limb of the internal capsule on cognition in depression

BACKGROUND

Preliminary studies report no negative and a possible positive impact of deep brain stimulation (DBS) on cognition of patients with treatment-resistant depression (TRD). However, these studies neither controlled for practice effects nor compared active with sham stimulation.

METHOD

To address these limitations, we compared 25 TRD patients, who underwent DBS of the ventral anterior limb of the internal capsule (vALIC), with 21 healthy controls (HCs) matched on gender, age and education level. Both groups did subtests of the Cambridge Neuropsychological Test Automated Battery assessing verbal and visuospatial memory, attention, cognitive flexibility, psychomotor functioning, planning and object naming. TRD patients were tested 3 weeks prior to DBS surgery (baseline), 3 weeks following surgery (T1) and following 52 weeks of DBS optimization (T2). HCs were tested at baseline, 6 weeks following baseline (T1) and 20-24 weeks following baseline (T2). Subsequently, TRD patients entered a randomized, double-blind crossover phase, in which they were tested in an active and a sham stimulation phase.

RESULTS

TRD patients did not improve on a test of immediate verbal recognition from baseline to T1, whereas HCs did (group x time: p = 0.001). Both TRD patients and HCs improved over sessions on tests measuring delayed verbal recall, visuospatial memory, planning and object naming (all p < 0.01). Active and sham stimulation did not have an impact on any of the tests differentially.

CONCLUSIONS

vALIC DBS neither has a lasting positive nor negative impact on cognition in TRD patients. DBS surgery might have a temporary negative effect on verbal memory.

Neuropsychological Predictors of Trauma Centrality in OIF/OEF Veterans

This study examined whether reduced performance on two neuropsychological tasks, cognitive flexibility and working memory, were associated with higher levels of trauma centrality. A growing body of research has shown that trauma centrality, the extent to which a person believes a potentially traumatic event has become central to their self-identity and life story, is associated with post-traumatic stress disorder (PTSD). Furthermore, PTSD is often associated with alterations in neuropsychological functioning. The relationship between neuropsychological processes and trauma centrality, however, has yet to be explored. OEF/OIF combat veterans (N = 41) completed the Post-traumatic Diagnostic Scale (PDS), the Beck Depression Inventory-II (BDI-II), the Centrality of Event Scale (CES), and on-line measures of cognitive flexibility and working memory assessed via WebNeuro. Bivariate Pearson correlations showed that CES scores were positively correlated with PDS and BDI scores, and negatively correlated with cognitive flexibility and working memory. Linear regressions revealed that working memory significantly predicted CES when controlling for depression and PTSD severity while cognitive flexibility approached significance when controlling for these same variables. This study employed a cross-sectional design, precluding causality. The small sample size, entirely male sample, and use of an online neuropsychological assessment warrant follow-up research. Although numerous studies have found an association between CES and PTSD, this is the first to suggest that neuropsychological processes underlie the construct of trauma centrality. Given the importance of maladaptive cognitive processes underlying the pathogenesis of PTSD, these data suggest that future studies aimed at examining the link between neuropsychological processes and maladaptive cognitive processes, such as trauma centrality, may help to characterize and treat PTSD.

Heterogeneity of Neuropsychological Impairment in HIV Infection: Contributions from Mild Cognitive Impairment

Despite longstanding acknowledgement of the heterogeneity of HIV-associated neurocognitive disorders (HAND), existing HAND diagnostic methods classify according to the degree of impairment, without regard to the pattern of neuropsychological strengths and weaknesses. Research in mild cognitive impairment (MCI) has demonstrated that classifying individuals into subtypes by both their level and pattern of impairment, using either conventional or statistical methods, has etiologic and prognostic utility. Methods for characterizing the heterogeneity of MCI provide a framework that can be applied to other disorders and may be useful in clarifying some of the current challenges in the study of HAND. A small number of studies have applied these methods to examine the heterogeneity of neurocognitive function among individuals with HIV. Most have supported the existence of multiple subtypes of neurocognitive impairment, with some evidence for distinct clinicodemographic features of these subtypes, but a number of gaps exist. Following a review of diagnostic methods and challenges in the study of HAND, we summarize the literature regarding conventional and empirical subtypes of MCI and HAND and identify directions for future research regarding neurocognitive heterogeneity in HIV infection.

Altered fractional amplitude of low frequency fluctuation associated with cognitive dysfunction in first-episode drug-naïve major depressive disorder patients

BACKGROUND

Previous studies have demonstrated that abnormities of both resting-state brain activity and cognitive dysfunction are frequently observed in patients with major depressive disorder (MDD). However, the underlying relationship between these two aspects is less investigated. In this context, the aim of the present study was to investigate the association between cognitive dysfunction and altered resting-state brain function in first-episode drug-naïve MDD patients.

METHODS

Twenty-five drug-naïve MDD patients and twenty-six age-, sex-, and education-matched normal controls were recruited in this study. Cognitive function was evaluated by using a series of validated test procedures. The resting-state functional magnetic resonance imaging data were obtained on a Philips 3.0 Tesla scanner and analysed using the fractional amplitude of low frequency fluctuation (fALFF) method. Correlations of fALFF values with cognitive dysfunction were further analysed.

RESULTS

Compared with healthy controls, MDD patients showed significantly fewer completed categories in the Wisconsin Card Sorting Test (WCST) and decreased scores in the first and second subtests of the Continuous Performance Test (CPT). However, the two groups did not differ in their performance on the Stroop Colour Word Test and Trail-making Test. MDD patients exhibited significantly decreased fALFF values in the left superior frontal gyrus (SFG), left middle frontal gyrus, and left inferior frontal gyrus, as well as increased fALFF values in the left inferior temporal gyrus (ITG), bilateral parahippocampal gyrus, and the right caudate. Finally, the correlation analyses revealed that fALFF values in the left SFG and left ITG were associated with the number of WSCT completed categories and scores on the second subtest of the CPT in MDD, respectively.

CONCLUSIONS

The present findings suggest that there is little evidence of an association between regional abnormalities in resting-state brain function and cognitive deficits in MDD.

Examining Nutrition Knowledge of Bariatric Surgery Patients: What Happens to Dietary Knowledge over Time?

BACKGROUND

Nutrition education is a standard of care in bariatric surgery clinical practice guidelines. Despite its known importance, no studies have documented the trajectory of nutrition knowledge over the course of the bariatric surgery process. Primary objectives included determining changes in bariatric surgery nutrition knowledge scores from the pre-surgical phase to 1-month post-surgical intervention and investigating the impact of time on nutrition education retention in bariatric patients. Secondary objectives focused on the relationship between patients' pre-operative anxiety and depression on nutrition knowledge retention.

METHODS

Prior to data collection, patients attended a nutrition education class and met with a registered dietitian. One hundred and nineteen consented patients eligible for bariatric surgery completed a nutrition knowledge questionnaire, Eating After Bariatric Surgery (EABS) prior to and 1 month following bariatric surgery.

RESULTS

Analyses revealed (1) patients' nutrition knowledge (measured by EABS) significantly increased from the pre-operative phase (M = 46.9; SD = 14.4) to the post-operative phase ((M = 56.9; SD = 14.1), t(118) = -8.01, p < .001); (2) time between the nutrition education class and patients' surgery significantly impacted knowledge retained; (3) patients with higher pre-operative levels of depression and anxiety had significantly lower post-operative nutrition knowledge; and (4) gender differences in terms of patients' nutrition knowledge.

CONCLUSIONS

This study confirmed that dietary knowledge significantly improves following surgical intervention. Furthermore, increased time in between receiving nutrition knowledge and surgery resulted in less retained knowledge 1-month post-op. Future education interventions for bariatric surgery programs should focus on addressing these factors to optimize patient knowledge and information retention after surgery.

[Cognition - the core of major depressive disorder]

Cognitive deficits have been only recently recognized as a major phenotype determinant of major depressive disorder, although they are an integral part of the definition of the depressive state. Congruent evidence suggest that these cognitive deficits persist beyond the acute phase and may be identified at all ages. The aim of the current study was to review the main meta-analyses on cognition and depression, which encompasses a large range of cognitive domains. Therefore, we discuss the "cold" (attention, memory, executive functions) and "hot" (emotional bias) cognitive impairments in MDD, as well as those of social cognition domains (empathy, theory of mind). Several factors interfere with cognition in MDD such as clinical (melancholic, psychotic...) features, age, age of onset, illness severity, medication and comorbid condition. As still debated in the literature, the type of relationship between the severity of cognitive symptoms and functioning in depression is detailed, thus highlighting their predictive value of functional outcome, independently of the affective symptoms. A better identification of the cognitive deficits in MDD and a monitoring of the effects of different treatments require appropriate instruments, which may be developed by taking advantage of the increasing success of computing tools. Overall, current data suggest a core role for different cognitive deficits in MDD, therefore opening new perspectives for optimizing the treatment of depression.

The relationship between face recognition ability and socioemotional functioning throughout adulthood

The relationship between face recognition ability and socioemotional functioning has been widely explored. However, how aging modulates this association regarding both objective performance and subjective-perception is still neglected. Participants, aged between 18 and 81 years, performed a face memory test and completed subjective face recognition and socioemotional questionnaires. General and social anxiety, and neuroticism traits account for the individual variation in face recognition abilities during adulthood. Aging modulates these relationships because as they age, individuals that present a higher level of these traits also show low-level face recognition ability. Intriguingly, the association between depression and face recognition abilities is evident with increasing age. Overall, the present results emphasize the importance of embedding face metacognition measurement into the context of these studies and suggest that aging is an important factor to be considered, which seems to contribute to the relationship between socioemotional and face-cognitive functioning.

Dual Tasking for the Differentiation between Depression and Mild Cognitive Impairment

Differentiation of mild cognitive impairment from depression in elderly adults is a clinically relevant issue which is not sufficiently solved. Gait and dual task (DT) parameters may have the potential to complement current diagnostic work-up, as both dementia and depression are associated with changes of gait and DT parameters.

METHODS

Seven hundred and four participants of the TREND study (Tübinger evaluation of Risk factors for Early detection of NeuroDegeneration) aged 50-80 years were assessed using the Consortium to Establish a Registry for Alzheimer's Disease Plus test battery for testing cognition and Beck's Depression Inventory for evaluation of depression. Based on these results, four groups were defined: acute depressed (N = 53), cognitively mildly impaired (N = 97), acute depressed, and cognitively mildly impaired (N = 15), and controls (N = 536). Participants underwent a 20 m walk and checking boxes task under single (ST) and DT conditions. ST and DT performance and dual task costs (DTC) were calculated. Due to the typical age of increasing incidence of depressive and also cognitive symptoms, the 7th decade was calculated separately.

RESULTS

ST speeds of gait and checking boxes, DT walking speed, and walking DTC were significantly different between groups. Healthy controls were the fastest in all paradigms and cognitively mildly impaired had higher DTC than depressed individuals. Additionally, we constructed a multivariate predictive model differentiating the groups on a single-subject level.

CONCLUSION

DT parameters are simply and comfortably measureable, and DTC can easily be determined. The combination of these parameters allows a differentiation of depressed and cognitively mildly impaired elderly adults.

Neuropsychological Outcome and its Predictors Across the First Year after Ischaemic Stroke

Background: Neuropsychological deficits occur in over half of the stroke survivors and are associated with the reduced functioning and a decline in quality of life. However, the trajectory of recovery and predictors of neuropsychological outcomes over the first year post stroke are poorly understood.

Method: Neuropsychological performance, assessed using the CNS-Vital signs, was examined at 1 month, 6 months and 12 months after ischaemic stroke (IS) in a sample drawn from a population-based study (N = 198).

Results: While mean scores across neuropsychological domains at each time-point fell in the average range, one in five individuals produced very low-range scores for verbal memory, attention and psychomotor speed. Significant improvements were seen for executive functioning, psychomotor speed and cognitive flexibility within 6 months post stroke, but no gains were noted from 6 to 12 months. Stroke-related neurological deficits and depression at baseline significantly contributed to the prediction of neuropsychological function at 12 month follow-up.

Conclusions: In a significant minority of IS survivors, focal deficits are evident in psychomotor speed, verbal memory, executive functions and attention. Significant improvements in these domains were only evident in the first 6 months post stroke. Initial stroke-related neurological deficits and concurrent depression may be the best predictors of later cognitive functioning.