Neuropsychological performance in partly remitted unipolar depressive patients: focus on executive functioning

A multinational analysis of how emotions relate to economic decisions regarding time or risk

Emotions have been theorized to be important drivers of economic choices, such as intertemporal or risky decisions. Our systematic review and meta-analysis of the previous literature (378 results and 50,972 participants) indicates that the empirical basis for these claims is mixed and the cross-cultural generalizability of these claims has yet to be systematically tested. We analysed a dataset with representative samples from 74 countries (n = 77,242), providing a multinational test of theoretical claims that individuals' ongoing emotional states predict their economic preferences regarding time or risk. Overall, more positive self-reported emotions generally predicted a willingness to wait for delayed rewards or to take favourable risks, in line with some existing theories. Contrary to the assumption of a universal relationship between emotions and decision-making, we show that these relationships vary substantially and systematically across countries. Emotions were stronger predictors of economic decisions in more economically developed and individualistic countries.

Association between cognitive functioning, suicidal ideation and suicide attempts in major depressive disorder, bipolar disorder, schizophrenia and related disorders: A systematic review and meta-analysis

INTRODUCTION

Treatable mental disorders, such as psychotic, major depressive disorder (MDD), and bipolar disorder (BD), contribute to a substantial portion of suicide risk, often accompanied by neurocognitive deficits. We report the association between cognitive function and suicidal ideation/suicide attempts (SI/SA) in individuals with schizoaffective disorder, BD, and MDD.

METHODS

A systematic search was conducted on PubMed, Ovid and Scopus databases for primary studies published from inception to April 2024. Eligible articles that reported on the effect size of association between cognition and SI/SA were pooled using a random effects model.

RESULTS

A total of 41 studies were included for analysis. There was a negative association between executive functioning and SI/SA in schizoaffective disorder (SA: Corr = -0·78, 95 % CI [-1·00, 0·98]; SI: Corr = -0·06, 95 % CI [-0·85, 0·82]) and MDD (SA: Corr = -0·227, 95 % CI [-0·419, -0·017]; SI: Corr = -0·14, 95 % CI [-0·33, 0·06]). Results were mixed for BD, with a significant positive association between SA and global executive functioning (Corr = 0·08, 95 % CI [0·01, 0·15]) and negative association with emotion inhibition. Mixed results were observed for processing speed, attention, and learning and memory, transdiagnostically.

LIMITATIONS

There is heterogeneity across sample compositions and cognitive measures. We did not have detailed information on individuals with respect to demographics and comorbidities.

CONCLUSIONS

We observed a transdiagnostic association between measures of cognitive functions and aspects of suicidality. The interplay of cognitive disturbances, particularly in reward-based functioning, may underlie suicidality in individuals with mental disorders. Disturbances in impulse control, planning, and working memory may contribute to self-injurious behavior and suicide.

Indirect effect of impulsivity on suicide risk through self-esteem and depressive symptoms in a population with treatment-resistant depression: A FACE-DR study

INTRODUCTION

Suicide is a major health issue. Its prevalence is particularly high in subjects presenting major depression disorder (MDD), making this a key suicide-related risk factor. Suicide attempts in severe forms of MDD were assumed to be linked to impulsivity and loss of control. Nevertheless, we failed to find data specifically investigating the link between impulsivity and suicide risk in treatment-resistant depression (TRD). This study seeks to review this relationship.

METHOD

Patients were recruited for a prospective cohort. Suicide risk and impulsivity were assessed using the International Neuropsychiatric Interview and Barratt Impulsiveness Scale, Version 10, respectively, while the severity of depressive symptoms was assessed using the Montgomery-Asberg Depression Rating Scale, anxiety with the State-Trait Anxiety Inventory and childhood maltreatment using the Childhood Trauma Questionnaire.

RESULTS

220 TRD patients were enrolled in the study. The impulsivity score was correlated with self-esteem, marital status, professional status and anxiety. There was no direct link to suicide risk. However, impulsivity was associated with self-esteem (coefficient: -0.24; p value 0.043) and depressive symptom severity (coefficient: 0.; p value 0.045). The suicide risk was significantly correlated with depressive symptom severity (coefficient = 0.38, p < 0.001) and self-esteem (coefficient = -0.34, p = 0.01). Considering these correlations, we postulated that the effect of impulsivity on suicide risk could be mediated by self-esteem in terms of depressive symptom severity and we finally found a relevant mediation model within impulsivity having an indirect effect on suicide risk by impacting self-esteem and depressive symptoms with anxiety also playing a significant role as a covariable.

CONCLUSION

We found that impulsivity could play an indirect role with the involvement of self-esteem and depressive symptoms and the contributing role of anxiety.

Risky decision-making in major depressive disorder: A three-level meta-analysis

Background

Individuals with major depressive disorder (MDD) are usually observed making inappropriate risky decisions. However, whether and to what extent MDD is associated with impairments in risky decision-making remains unclear. We performed a three-level meta-analysis to explore the relationship between risky decision-making and MDD.

Method

We searched the Web of Science, PubMed, Scopus, and PsycINFO databases up to February 7, 2023, and calculated Hedges' g to demonstrate the difference in risky decision-making between MDD patients and healthy controls (HCs). The moderating effect of sample and task characteristics were also revealed.

Results

Across 73 effect sizes in 39 cross-sectional studies, MDD patients exhibited greater risk-seeking than HCs (Hedges' g = 0.187, p = .030). Furthermore, age (p = .068), region (p = .005), and task type (p < .001) were found to have moderating effects. Specifically, patients preferred risk-seeking over HCs as age increased. European patients showed significantly increased risk-seeking compared to American and Asian patients. Patients in the Iowa Gambling Task (IGT) exhibited a notable rise in risk-seeking compared to other tasks, along with an increased risk aversion in the Balloon Analogue Risk Task (BART). The multiple-moderator analysis showed that only task type had significant effects, which may be explained by a tentative framework of "operationalization-mechanism-measure" specificity.

Conclusions

MDD patients generally exhibit higher risk-seeking than HCs. It implies that impaired risky decision-making might be a noteworthy symptom of depression, which should be placed more emphasis for clinical management and psycho-education.

Impulsivity in Depression: Its Relation to Suicidality

OBJECTIVE

Impulsivity is an important risk for suicidality, which is common in patients with major depressive disorder (MDD). The goal of this study was to examine multiple facets of impulsivity in depressed patients compared with healthy controls and to assess their relationship to suicidality.

METHOD

Outpatients diagnosed with MDD using the Structured Clinical Interview for DSM-IV were recruited. Two groups were constituted as "MDD in remission" (n=32) and "MDD" (n=71). The "healthy control" group (n=30) consisted of individuals who had never been diagnosed with any psychiatric disorder. Impulsivity was assessed with the Barratt Impulsivity Scale (BIS), a self-rating measure, and with the following behavioral tasks: Go/No-go Task, Iowa Gambling Task, and Balloon Analogue Risk Task. The scores of the 3 groups (n=133) were compared to evaluate the effect of MDD. The scores were also analyzed and compared in the patients in the 2 MDD groups (n=103) with respect to their current and lifetime suicidality.

RESULTS

There was no difference in the 3 groups in task scores, but nonplanning BIS was correlated with the severity of depressive symptoms. Patients with suicidal ideation (SI) had higher BIS total and attention impulsivity scores and more commission errors on the Go/No-go Task, reflecting failure in response inhibition, compared with the patients without SI.

CONCLUSIONS

Failure to show differences in impulsivity-related tasks suggests that there might be no relationship between the state of depression and impulsivity. However, these findings confirm that there is an association between SI and response inhibition and the attention facet of impulsivity in depression.

Impairment of response inhibition to emotional face stimuli in individuals with subclinical depression

Response inhibition, a crucial component of executive function, is closely related to personal impulse control, social adaption, and mental health. Previous studies have found response inhibition deficit in patients with major depressive disorder, but whether it also exists in individuals with subclinical depression (SD) remains unclear. This study aimed to identify the ability of response inhibition to emotional face stimuli both under explicit and implicit conditions in individuals with SD. Thirty-six subclinical depressed college students and 39 healthy individuals were recruited and administered the non-emotional, explicit, and implicit emotional stop-signal tasks (SSTs). Mixed-model analyses of variance were used to analyze the differences between and within groups. In implicit emotional SST, the results showed a significant longer stop-signal response time, a shorter stop-signal delay time, a shorter go reaction time, and a similar proportion of stop success in the SD group compared to healthy controls. However, the above indices showed no significant difference between the two groups in the non-emotional SST and explicit emotional SST. These findings suggest a possible defect of response inhibition in implicit emotional processing in individuals with SD, which may potentially serve as a marker of susceptibility to depression and thus be applied to early screening and intervention for major depressive disorder.

Assessing Pragmatic Language Skills in Adults with Major Depressive Disorder: An Exploratory Study

INTRODUCTION

There is increasing evidence that major depressive disorder (MDD) is associated with significant pragmatic language impairments. However, there is a lack of studies that use standardized tools and simultaneously investigate all pragmatic language skills among MDD patients. The aim of this study was to propose a more thorough investigation of all pragmatic language skills in patients with MDD.

METHODS

Twenty adults (aged 22-65) with a DSM-5 diagnosis of MDD were assessed using BLED Santa Lucia (Batteria sul Linguaggio dell'Emisfero Destro Santa Lucia), a battery designed to evaluate pragmatic language skills (comprehension of inferences, of picture and written metaphors, of indirect requests, of humoristic expressions, and of prosody). The performance of the MDD participants on all BLED Santa Lucia subscales was compared to 20 healthy control subjects (aged 20-60) matched for gender, age, years of education, and employment status.

RESULTS

MDD patients performed poorer than controls in comprehension of inferences (p < 0.01), picture metaphors (p < 0.001), written metaphors (p < 0.001), indirect requests (p < 0.01), humoristic expression (p < 0.05), and prosody (p < 0.05).

CONCLUSIONS

All pragmatic language skills can be significantly impaired in MDD patients. A valid assessment of all pragmatic language skills can allow, for each patient, the definition of a specific profile of risk and protective factors before and during psychotherapy.

Performances on individual neurocognitive tests by people experiencing a current major depression episode: A systematic review and meta-analysis

BACKGROUND AND PURPOSES

Previous meta-analyses on neurocognitive test performances in depression have provided effect sizes for cognitive domains. Most domain effect sizes have medium to high variance heterogeneity. Restriction to each test performance could reduce variance and clarify differing test effect sizes. This systematic review and meta-analysis were done to 1. provide effect sizes for cognitive performances (test, subtest, or multiple measures within tests), and 2. investigate age as an effect modifier.

METHODS

Inclusion criteria were: 1. active major depression episode (MD), 2. a control group, 3 reported means and standard deviations, 4. non-computerized tests previously studied at least 3 times. Meta-analyses were performed using Cochrane Review Manager. Age under versus over 45 was investigated as an effect moderator.

RESULTS

Twenty-seven studies met criteria. MD patients performed significantly poorer on 16 of 16 neurocognitive measures (random effects d = -0.47 to -0.92 across tests). Variance was heterogeneous for 11 of 16 measures. Differences between cognitive measures were largely absent based on overlapping 95% confidence intervals. Effect sizes did not differ under versus over 45 years.

LIMITATIONS

Bias risk assessment showed limited control for subject selection, comparability of depressed and control groups, pre-morbid intelligence, drug treatment, and effort in testing.

CONCLUSIONS

The depression - cognition effect was in the moderate to large range regardless of test type. Variance heterogeneity was substantial despite exclusion of inactive depression and the absence of test pooling. The size of the depression - cognition effect was not a function of age.

Attention deficits in adults with Major depressive disorder: A systematic review and meta-analysis

Attention deficits have been proven in patients with major depressive disorder (MDD). However, a detailed characterization of attention deficits in MDD was unclear. The aim of current study was to explore the specific deficits of attention in different sub-domains of attention so as to produce an overall picture of contemporary research on this field. We performed a systematic review and meta-analysis of published researches. PubMed, EMBASE, Cochrane Library and review of references were searched up to October 2019. Studies using at least one objective measurement to assess attention performances of MDD patients were included. Effect sizes were calculated using random-effects models for attention outcomes. Publication bias was evaluated using Egger's test. Twenty-three eligible studies including 1371 MDD patients were enrolled in this meta-analysis. Significant deficit of global attention was observed. For the specific outcomes, MDD patients showed significant deficits in psychomotor speed/attention, auditory attention, visuo-spatial attention, sustained visual attention, ranging from small to moderate, but not in selective attention. Larger sample sizes and more detailed subgroup analyses based on features of patients should be conducted to produce a more accurate conclusion.

Impulsivity differences between bipolar and unipolar depression

BACKGROUND

Even though particularly bipolar depression and unipolar depression seem to be similar, they show differences in terms of the etiology, phenomenology, course, and treatment process. Bipolar depression is associated with mood lability, motor retardation, and hypersomnia to a larger extent. Early age of onset, a high frequency of depressive episodes, and history of bipolar disease in the family are suggestive of bipolar disorder (BD) rather than major depression. Bipolar and unipolar disorders are also associated with increased impulsivity during illness episodes. However, there is little information about impulsivity during euthymia in these mood disorders. The aim of this study was to illustrate the difference in impulsivity in euthymic bipolar and unipolar patients.

MATERIALS AND METHODS

Impulsivity was evaluated by the Barratt Impulsiveness Scale (BIS-11A), in 78 interepisode BD patients, 72 interepisode unipolar disorder patients, and 70 healthy controls. The diagnosis was established by severe combined immunodeficiency. One-way between-groups ANOVA was used to compare the BIS-11A mean scores for all three groups.

RESULTS

Impulsivity scores of the bipolar and unipolar disorder patients were significantly higher than controls on total and all subscales measures. There was no difference between the bipolar and unipolar disorder groups on total, attentional, and nonplanning impulsivity measures. However, BD patients scored significantly higher than the unipolar patients on motor impulsivity measures.

CONCLUSIONS

Both interepisode bipolar and unipolar disorder patients had increased impulsivity compared to healthy individuals. There was no significant difference on attention and nonplanning impulsivity subscales; however, on the motor subscale, bipolar patients were more impulsive than unipolar disorder patients.

Neurocognitive performance in patients with depression compared to healthy controls: Association of clinical variables and remission state

Cognitive impairment in Major Depressive Disorder (MDD) has been postulated to persist into remission. However, inconsistent definitions of clinical remission, patterns and influencing factors, isolated cognitive tasks, and the lack of appropriately matched controls (HCs) present significant limitations of previous studies. Furthermore, studies investigating cognition in partially remitted patients are particularly scarce. This study compares the cognition of MDD patients (N = 65) and HCs (N = 65), matched by one-to-one recruitment strategy for age, sex, and education (ages 19-60). The neuropsychological (NPS) performance was measured via an extensive NPS-test battery and analysed retrospectively, accounting for demographic and clinical variables. Full remission was defined as HAMD cut off ≤7, partial remission as HAMD 8-18. The findings show entire MDD group and partially remitted MDD with significantly poorer NPS performance compared to HCs, while remitted MDD patients did not differ significantly from HCs. This underscores how critical a clear definition of remission is to compare studies on MDD. The clinical variable 'number of hospitalizations' had a significant effect on cognition, whereas current symptom severity did not correlate with performance on any cognitive domain. Higher number of hospitalizations may be associated with higher burden of illness and greater neurobiological "scar effects".

Neuropsychological changes in melancholic and atypical depression: A systematic review

There is not a consensus as to whether neuropsychological profiling can distinguish depressive subtypes. We aimed to systematically review and critically analyse the literature on cognitive function in patients with melancholic and atypical depression. We searched in databases PubMed, SCOPUS, Web of Knowledge and PsycInfo for papers comparing the neuropsychological performance of melancholic patients (MEL) to non-melancholic depressive patients (NMEL), including atypical depressives, and healthy controls (HC). All studies were scrutinised to determine the main methodological characteristics and particularly possible sources of bias influencing the results reported, using the STROBE statement checklist. We also provide effect size of the results reported for contrasts between MEL; patients and NMEL patients. Seventeen studies were included; most of them demonstrated higher neuropsychological impairments of MEL patients compared to both NMEL patients and HC on tasks requiring memory, executive function, attention and reaction time. Detailed analysis of the methodologies used in the studies revealed significant variability especially regarding the participants' sociodemographic characteristics, clinical characteristics of patients and differences in neuropsychological assessment. These findings suggest that MEL may have a distinct and impaired cognitive performance compared to NMEL depressive patients on tasks involving verbal and visual memory, executive function, sustained attention and span, as well as psychomotor speed, this last especially when cognitive load is increased. Additional studies with adequate control of potentially confounding variables will help to clarify further differences in the neuropsychological functioning of depressive subtypes.

How can Continuous Performance Test help to assess inattention when mood and ADHD symptoms coexist?

Depression and attention-deficit/hyperactivity disorder (ADHD) are prevalent, and often comorbid, disorders, with varying severity levels among patients. Inattention is a symptom present in both disorders, which often makes their differential diagnosis difficult in clinical practice (depression only versus comorbidity). This study aimed to investigate the influence of depressive symptoms on attention performance using one of the most common tasks in clinical practice, the continuous performance test (CPT). Ninety-three college students (60 men, 33 women) with a mean age of 24 years old were investigated with self-reports and semi-structured interviews for ADHD; the Beck Depression Inventory (BDI) was used for depression ratings. Attention measures were derived from the CPT. There was no correlation between depression and ADHD symptoms; in addition, depression was not correlated with any of the CPT scores; ADHD symptomatology was the only predictor of changes in those CPT variables (commission and omission errors and d prime). ADHD-associated impairment on the CPT was not augmented by the presence of depressive symptoms, making neuropsychological results on this test helpful for the differential diagnosis. When attention deficits are observed in individuals with mild or moderate depression, they are most likely not attributed to depression.

Role of Reward Sensitivity and Processing in Major Depressive and Bipolar Spectrum Disorders

Since Costello's (1972) seminal Behavior Therapy article on loss of reinforcers or reinforcer effectiveness in depression, the role of reward sensitivity and processing in both depression and bipolar disorder has become a central area of investigation. In this article, we review the evidence for a model of reward sensitivity in mood disorders, with unipolar depression characterized by reward hyposensitivity and bipolar disorders by reward hypersensitivity. We address whether aberrant reward sensitivity and processing are correlates of, mood-independent traits of, vulnerabilities for, and/or predictors of the course of depression and bipolar spectrum disorders, covering evidence from self-report, behavioral, neurophysiological, and neural levels of analysis. We conclude that substantial evidence documents that blunted reward sensitivity and processing are involved in unipolar depression and heightened reward sensitivity and processing are characteristic of hypomania/mania. We further conclude that aberrant reward sensitivity has a trait component, but more research is needed to clearly demonstrate that reward hyposensitivity and hypersensitivity are vulnerabilities for depression and bipolar disorder, respectively. Moreover, additional research is needed to determine whether bipolar depression is similar to unipolar depression and characterized by reward hyposensitivity, or whether like bipolar hypomania/mania, it involves reward hypersensitivity.

Dysfunctional decision-making related to white matter alterations in bipolar I disorder

OBJECTIVE

This study investigated how frontal white matter (WM) alterations in patients with bipolar I disorder (BD-I) are linked to motivational dysregulation, often reported in the form of risk-taking and impulsivity, and whether structure-function relations in patients might differ from healthy subjects (HC).

METHOD

We acquired diffusion data from 24 euthymic BD-I patients and 24 controls, to evaluate WM integrity of selected frontal tracts. Risk-taking was assessed by the Cambridge Gambling Task and impulsivity by self-report with the Barratt-Impulsiveness Scale.

RESULTS

BD-I patients displayed significantly lower integrity in the right cingulum compared to HC. They also showed more risk-taking behavior and reported increased trait-impulsivity. Risk-taking was negatively associated with WM integrity in the right cingulum. Impulsivity was not related to WM integrity in investigated tracts. Together with age and sex, FA in the cingulum explained 25% of variance in risk-taking scores in all study participants. The left inferior fronto-occipital fasciculus (IFOF) was specifically predictive of risk-taking behavior in BD-I patients, but not in HC.

LIMITATIONS

The employed parameters did not allow us to specify the exact origin of WM changes, nor did the method allow the analysis of specific brain subregions. Also, sample size was moderate and the sample included patients with lifetime alcohol dependence/abuse, hence effects found need replication and have to be interpreted with caution.

CONCLUSION

Our results further strengthen recent models linking structural changes in frontal networks to behavioral markers of BD-I. They extend recent findings by showing that risk-taking is also linked to the cingulum in BD-I and HC, while other prefrontal tracts (IFOF) are specifically implicated in risk-taking behavior in BD-I patients. Meanwhile, self-reported impulsivity was not associated with WM integrity of the tracts investigated in our study.

Inhibition and response to error in remitted major depression

Depression is a common illness which tends to have a relapsing progression. Revealing vulnerability factors is an important step towards improved treatment and prevention. Previous studies of individuals in remission indicate that inhibitory control is more strongly impaired than other cognitive functions. Studies have mostly used Stroop tasks; it is unclear how this population performs on other measures of inhibition. Abnormal reactions to errors may also promote depression relapse, but this has rarely been studied in remitted depression. We used a Stop Signal task and Stroop inhibition task to investigate inhibitory function and post-error reaction time adjustments in 54 individuals with a history of depression and 185 never-depressed controls. Inhibitory processing was slower among the remitted depressed individuals on the Stop Signal task, but no difference was found in Stroop inhibition. The groups were not different on post-error adjustments. This finding extends the understanding of inhibitory deficiency in this population and offers insight into trait markers of depression.

Effects of remission speed and improvement of cognitive functions of depressed patients

Major depressive disorder (MDD) presents neuropsychological alterations which improve after the treatment, but it might be mediated by clinical variables. Our goal is to study whether the speed of remission of MDD bears any relation to the improvement of the patients' cognitive functioning after a successful treatment. We carried out clinical and neuropsychological assessments of 51 patients with MDD. After these procedures they underwent a 24-week treatment with fluoxetine, and were assessed again with the same battery used prior to treatment. They were arranged into three groups according to how rapid their symptoms remitted. The patients with a rapid remission presented improvements in working memory, speed of information processing, and some executive functions, unlike the other groups. Rapid remitters also improved in episodic memory and executive functions more than the other patients.

Mechanisms Underlying Motivational Deficits in Psychopathology: Similarities and Differences in Depression and Schizophrenia

Motivational and hedonic impairments are core aspects of a variety of types of psychopathology. These impairments cut across diagnostic categories and may be critical to understanding major aspects of the functional impairments accompanying psychopathology. Given the centrality of motivational and hedonic systems to psychopathology, the Research Domain Criteria (RDoC) initiative includes a "positive valence" systems domain that outlines a number of constructs that may be key to understanding the nature and mechanisms of motivational and hedonic impairments in psychopathology. These component constructs include initial responsiveness to reward, reward anticipation or expectancy, incentive or reinforcement learning, effort valuation, and action selection. Here, we review behavioral and neuroimaging studies providing evidence for impairments in these constructs in individuals with psychosis versus in individuals with depressive pathology. There are important differences in the nature of reward-related and hedonic deficits associated with psychosis versus depression that have major implications for our understanding of etiology and treatment development. In particular, the literature strongly suggests the presence of impairments in in-the-moment hedonics or "liking" in individuals with depressive pathology, particularly among those who experience anhedonia. Such deficits may propagate forward and contribute to impairments in other constructs that are dependent on hedonic responses, such as anticipation, learning, effort, and action selection. Such hedonic impairments could reflect alterations in dopamine and/or opioid signaling in the striatum related to depression or specifically to anhedonia in depressed populations. In contrast, the literature points to relatively intact in-the-moment hedonic processing in psychosis, but provides much evidence for impairments in other components involved in translating reward to action selection. Particularly, individuals with schizophrenia exhibit altered reward prediction and associated striatal and prefrontal activation, impaired reward learning, and impaired reward-modulated action selection.

An exploratory analysis of Go/Nogo event-related potentials in major depression and depression following traumatic brain injury

Rates of major depressive disorder (MDD) following traumatic brain injury (TBI) are estimated to be between 20% and 45%, a higher prevalence than that seen in the general population. These increased rates may be due to specific changes in brain function following TBI. Event related potentials (ERPs) are well suited for measuring the electrophysiological differences between groups in areas of cognitive processing impaired in both MDD and TBI, such as response inhibition. The current study presented an emotional Go/Nogo task (with schematic emotional faces as stimuli) to participants with TBI, participants with MDD, and participants with both TBI and MDD (TBI-MDD). Topographical distribution of activity and global field power comparisons were made across stimulus-locked epochs between these groups and healthy controls. The results indicated that ERPs were not altered by TBI alone. Both MDD and TBI-MDD groups showed similar alterations in topographical distribution and global field power in the N2 window, as well as late epoch alterations. The MDD and TBI-MDD groups showed significantly less fronto-central negativity during the N2 window in Nogo trials compared with the control group. The MDD and TBI-MDD groups also showed significantly less global field power in Nogo trials than Go trials during the N2 window while the control group showed the opposite pattern. The MDD and TBI-MDD groups showed no mood-congruent bias in behavioural or ERP measures. The results suggest that TBI-MDD displays similar electrophysiological changes to those found in the MDD group without TBI.

Impulsivity in remitted depression: a meta-analytical review

AIM

Depressive disorder and suicide have been associated with impulsivity in several studies. This paper aimed to review measures of trait impulsivity in remitted depressive disorder.

METHODS

We used keywords "impulsivity and depression"; "impulsivity and depressive disorder" to narrow down our search on Medline, EMBASE and Psychinfo to include those studies that had reported impulsivity scores using validated and reliable assessment measures in remitted depressive disorder. We searched all English language studies from 1990 to December 2012 with 9 reports meeting the inclusion criteria for depression, which were then reviewed by the two reviewers independently. We generated weighted mean differences (WMDs) for depression from the pooled data using RevManager 5.1 from Cochrane analysis.

RESULTS

The Barratt Impulsivity Scale (BIS) 11 was the instrument commonly used in depression. 9 studies met inclusion criteria in depression, which yielded a WMD of 10.12 on BIS 11 total scores.

CONCLUSION

There is a strong association of impulsivity and depression, which persists even in remission.

A sib-pair analysis of impulsivity in bipolar disorder type I

OBJECTIVE

The aim of this study was to compare impulsivity among patients with bipolar disorder, their siblings, and healthy controls in order to examine whether impulsivity in bipolar disorder is related to genetic liability for the illness.

METHODS

Using the Barratt Impulsiveness Scale, we assessed 204 subjects: 67 euthymic outpatients with bipolar disorder type I, 67 siblings without bipolar disorder, and 70 healthy controls.

RESULTS

Impulsivity scores were higher among patients with bipolar disorder than among healthy controls. Siblings showed higher motor impulsivity scores than did healthy controls.

CONCLUSIONS

Our results suggest that motor impulsivity may be a vulnerability marker for bipolar disorder. Our data may contribute to further improve preventive strategies in subjects at high risk for bipolar disorder.

Polysubstance dependent patients display a more utilitarian profile in moral decision-making than alcohol-dependent patients, depressive patients and controls

BACKGROUND

Addiction has been shown to be associated with the endorsement of utilitarian moral judgments. Ventro-medial prefrontal cortex (VMPFC) dysfunction may explain these findings.

METHODS

100 subjects were recruited: 25 polysubstance dependent patients, 25 alcohol dependent patients, 25 patients with major depressive disorders, and 25 normal controls. Subjects were assessed with a battery of 24 moral dilemmas: 8 impersonal dilemmas (no physical contact involved); 8 personal pareto (direct action that does not make the harmed individual worse off) and 8 personal non-pareto (direct action that does make the harmed individual worse off). The Iowa Gambling Task was used to document a possible connection between VMPFC dysfunction and responses to the moral dilemmas.

RESULTS

Polysubstance dependent patients endorsed more utilitarian choices than controls on all types of dilemmas and more than depressed patients on impersonal and personal pareto dilemmas. Alcohol dependent patients had intermediate results between polysubstance dependent patients and controls but these differences were not significant. All patients showed significantly poorer performance compared to controls on the Iowa Gambling Task, but there was no significant association between Iowa Gambling Tasks scores and moral dilemma choices.

CONCLUSION

Polysubstance dependent patients made more utilitarian choices when responding to moral dilemmas than depressed patients and normal controls, while alcoholic patients showed intermediate results. The absence of correlation between performance on the Iowa Gambling Task and the number of more utilitarian choices indicates that moral dilemma and decision making under uncertainty tap into separate mechanisms.

A follow-up study of first episode major depressive disorder. Impairment in inhibition and semantic fluency-potential predictors for relapse?

The present study investigated the Executive Functions (EF) of inhibition, mental flexibility and phonemic and semantic fluency in a 1-year follow-up assessment of patients diagnosed with first episode Major Depressive Disorder (MDD). In the acute phase, the patient group performed significantly poorer compared to the control group (CG) in inhibition and semantic fluency. The present study pursued these findings from the acute phase to see if the impairment seen in inhibition and semantic fluency in the acute phase normalized or persisted in the follow-up assessment. In addition, the present study investigated the association between poor inhibition and semantic fluency performance and the experience of relapse during the 1-year period. Twenty eight patients and 28 individually matched control subjects were included. EF was reassessed using three tests from the Delis Kaplan Executive Function System (D-KEFS).

RESULTS

There was a significant decrease in depression severity score from the acute phase, showing that most of the patients were in remission in the follow-up assessment. RESULTS showed a sustained impairment in inhibition and semantic fluency in the patient group. However, the performance in inhibition was more severe when an additional requirement of mental flexibility was included. There were no group differences in the other EF functions measured. Further, patients with a relapse in the course of 1 year performed significantly poorer in inhibition/switching at inclusion compared to patients that did not relapse and the CG. This relationship was not found for semantic fluency. Poor performance in inhibition and semantic fluency are prolonged despite symptom reduction in patients with a first episode of MDD. Moreover, although based on a small sample of patients, the present study showed that there may be a relationship between impaired ability in the EF of inhibition/switching and vulnerability for the experience of relapse.

Iowa gambling task performance in currently depressed suicide attempters

Deficits in decision-making using the Iowa Gambling Task (IGT) have been found in past suicide attempters, but primarily euthymic and/or medicated patients. This study compared IGT performance among medication-free, currently depressed patients (unipolar and bipolar) with (n=26) and without (n=46) a past history of suicide attempt, and healthy volunteers (n=42). Attempter status, in a sample whose attempts were predominantly non-violent, was not associated with impaired IGT performance even when accounting for sex, mood disorder type, and comorbid Borderline Personality Disorder. A non-significant trend towards poorer performance was found in a small subgroup of past attempters who had used a violent method, consistent with prior studies. Suicide intent and ideation were unrelated to IGT scores. There were no consistent associations between IGT performance and ratings of impulsiveness (Barratt Impulsiveness Scale (BIS)), hostility (Buss-Durkee Hostility Inventory (BDHI)) or aggression (Brown-Goodwin Aggression Inventory (BGAI)). Results suggest that decision-making impairment is related to specific subtypes of suicidal behavior, but may not be universally sensitive to suicide risk in all types of attempters, especially those using non-violent means. Psychometric and conceptual issues surrounding the IGT also appear to affect its utility as a general marker of suicidal behavior risk.

Major depressive disorder is associated with broad impairments on neuropsychological measures of executive function: a meta-analysis and review

Cognitive impairments are now widely acknowledged as an important aspect of major depressive disorder (MDD), and it has been proposed that executive function (EF) may be particularly impaired in patients with MDD. However, the existence and nature of EF impairments associated with depression remain strongly debated. Although many studies have found significant deficits associated with MDD on neuropsychological measures of EF, others have not, potentially due to low statistical power, task impurity, and diverse patient samples, and there have been no recent, comprehensive, meta-analyses investigating EF in patients with MDD. The current meta-analysis uses random-effects models to synthesize 113 previous research studies that compared participants with MDD to healthy control participants on at least one neuropsychological measure of EF. Results of the meta-analysis demonstrate that MDD is reliably associated with impaired performance on neuropsychological measures of EF, with effect sizes ranging from 0.32 to 0.97. Although patients with MDD also have slower processing speed, motor slowing alone cannot account for these results. In addition, some evidence suggests that deficits on neuropsychological measures of EF are greater in patients with more severe current depression symptoms, and those taking psychotropic medications, whereas evidence for effects of age was weaker. The results are consistent with the theory that MDD is associated with broad impairment in multiple aspects of EF. Implications for treatment of MDD and theories of EF are discussed. Future research is needed to establish the specificity and causal link between MDD and EF impairments.

Cognitive functioning in euthymic recurrently depressed patients: relationship with future relapses and prior course of disease

BACKGROUND

Cognitive impairment seems to persist during the euthymic phase of recurrent depression but its relationship with future relapses as with prior course of the disease has to be elucidated. The purpose of this study is to investigate the presence and prognostic value of cognitive dysfunctions for relapse in high risk euthymic patients and to identify relevant associations between cognitive functioning and prior course of illness.

METHODS

Standardized neuropsychological tests of mental speed, memory and executive functioning were assessed in 137 remitted patients and compared with clinically used published normative data. Previous episodes and relapses within 24 months were measured using the Structured Clinical Interview for DSM-IV.

RESULTS

Cognitive performance was significantly impaired on 12 of the 14 variables indicating deficits in the domain of speed of information processing and memory. With Cox regression no significant neuropsychological predictors for relapse or recurrence were identified. Furthermore, Pearson correlations between neuropsychological test scores and number of previous episodes, residual depressive symptoms and duration of remission were non-significant. Later age of onset was correlated with a slower speed of information processing and lower verbal memory performance.

LIMITATIONS

Published test reference data were used but no healthy control group.

CONCLUSION

Presence of mild cognitive impairment in remitted patients was demonstrated but did not predict future relapses nor was it related with prior course of disease except for age of onset. Though, mild cognitive impairment after remission might have an impact on the quality of life, adding techniques from cognitive rehabilitation might prove to be a treatment option.

Prediction of remission of depression with clinical variables, neuropsychological performance, and serotonergic/dopaminergic gene polymorphisms

OBJECTIVE

The aim of our work is to study the possible role of clinical variables, neuropsychological performance, and the 5HTTLPR, rs25531, and val108/58Met COMT polymorphisms on the prediction of depression remission after 12 weeks' treatment with fluoxetine. These variables have been studied as potential predictors of depression remission, but they present poor prognostic sensitivity and specificity by themselves.

METHODS

Seventy-two depressed patients were genotyped according to the aforementioned polymorphisms and were clinically and neuropsychologically assessed before a 12-week fluxetine treatment.

RESULTS

Only the La allele of rs25531 polymorphism and the GG and AA forms of the val 108/158 Met polymorphism predict major depressive disorder remission after 12 weeks' treatment with fluoxetine. None of the clinical and neuropsychological variables studied predicted remission.

CONCLUSIONS

Our results suggest that clinical and neuropsychological variables can initially predict early response to fluoxetine and mask the predictive role of genetic variables; but in remission, where clinical and neuropsychological symptoms associated with depression tend to disappear thanks to the treatment administered, the polymorphisms studied are the only variables in our model capable of predicting remission. However, placebo effects that are difficult to control require cautious interpretation of the results.

A meta-analysis of cognitive deficits in first-episode Major Depressive Disorder

BACKGROUND

Recurrent-episode Major Depressive Disorder (MDD) is associated with a number of neuropsychological deficits. To date, less is known about whether these are present in the first-episode. The current aim was to systematically evaluate the literature on first-episode MDD to determine whether cognition may be a feasible target for early identification and intervention.

METHODS

Electronic database searches were conducted to examine neuropsychological studies in adults (mean age greater than 18 years old) with a first-episode of MDD. Effect sizes were pooled by cognitive domain. Using meta-regression techniques, demographic and clinical factors potentially influencing heterogeneity of neuropsychological outcome were also investigated.

RESULTS

The 15 independent samples reviewed yielded data for 644 patients with a mean age of 39.36 years (SD=10.21). Significant cognitive deficits were identified (small to medium effect sizes) for psychomotor speed, attention, visual learning and memory, and all aspects of executive functioning. Symptom remission, inpatient status, antidepressant use, age and educational attainment, each significantly contributed to heterogeneity in effect sizes in at least one cognitive domain.

LIMITATIONS

Reviewed studies were limited by small sample sizes and often did not report important demographic and clinical characteristics of patients.

CONCLUSIONS

The current meta-analysis was the first to systematically demonstrate reduced neuropsychological functioning in first-episode MDD. Psychomotor speed and memory functioning were associated with clinical state, whereas attention and executive functioning were more likely trait-markers. Demographic factors were also associated with heterogeneity across studies. Overall, cognitive deficits appear to be feasible early markers and targets for early intervention in MDD.

Decision making under stress: a selective review

Many decisions must be made under stress, and many decision situations elicit stress responses themselves. Thus, stress and decision making are intricately connected, not only on the behavioral level, but also on the neural level, i.e., the brain regions that underlie intact decision making are regions that are sensitive to stress-induced changes. The purpose of this review is to summarize the findings from studies that investigated the impact of stress on decision making. The review includes those studies that examined decision making under stress in humans and were published between 1985 and October 2011. The reviewed studies were found using PubMed and PsycInfo searches. The review focuses on studies that have examined the influence of acutely induced laboratory stress on decision making and that measured both decision-making performance and stress responses. Additionally, some studies that investigated decision making under naturally occurring stress levels and decision-making abilities in patients who suffer from stress-related disorders are described. The results from the studies that were included in the review support the assumption that stress affects decision making. If stress confers an advantage or disadvantage in terms of outcome depends on the specific task or situation. The results also emphasize the role of mediating and moderating variables. The results are discussed with respect to underlying psychological and neural mechanisms, implications for everyday decision making and future research directions.

Impulsivity in euthymic patients with major depressive disorder: the relation to sociodemographic and clinical properties

The purpose of this study was to examine the trait impulsivity of patients with a major depressive disorder and to explore the possible connections between impulsivity and clinical and sociodemographic variables. The sociodemographic and clinical properties of 60 patients with major depression, who were euthymic according to Hamilton Depression Scale scores, were recorded. Their trait impulsivity was evaluated using the Barratt Impulsiveness Scale (BIS-11) and the impulsivity subscale of the Temperament and Character Inventory, and the results were compared with those of 50 age- and sex-matched healthy controls. We used general linear model analysis to evaluate the manner in which the variables contributed to BIS-11 scores. Some impulsivity scores were higher in those with a major depressive disorder than in comparison subjects. There were significant effects of education and sex in these differences. Elevated BIS-11 scores were associated with a history of psychotic mood episode and suicide attempts. These relationships persisted when age, sex, and education were taken into account. These results show that, after accounting for common confounding factors, trait-like impulsivity was substantially higher in subjects with major depressive disorder than in comparison subjects and may be associated with sociodemographic and clinical properties.

The role of clinical variables, neuropsychological performance and SLC6A4 and COMT gene polymorphisms on the prediction of early response to fluoxetine in major depressive disorder

INTRODUCTION

Major depressive disorder (MDD) is treated with antidepressants, but only between 50% and 70% of the patients respond to the initial treatment. Several authors suggested different factors that could predict antidepressant response, including clinical, psychophysiological, neuropsychological, neuroimaging, and genetic variables. However, these different predictors present poor prognostic sensitivity and specificity by themselves. The aim of our work is to study the possible role of clinical variables, neuropsychological performance, and the 5HTTLPR, rs25531, and val108/58Met COMT polymorphisms in the prediction of the response to fluoxetine after 4weeks of treatment in a sample of patient with MDD.

METHODS

64 patients with MDD were genotyped according to the above-mentioned polymorphisms, and were clinically and neuropsychologically assessed before a 4-week fluoxetine treatment. Fluoxetine response was assessed by using the Hamilton Depression Rating Scale. We carried out a binary logistic regression model for the potential predictive variables.

RESULTS

Out of the clinical variables studied, only the number of anxiety disorders comorbid with MDD have predicted a poor response to the treatment. A combination of a good performance in variables of attention and low performance in planning could predict a good response to fluoxetine in patients with MDD. None of the genetic variables studied had predictive value in our model.

LIMITATIONS

The possible placebo effect has not been controlled. Our study is focused on response prediction but not in remission prediction.

CONCLUSIONS

Our work suggests that the combination of the number of comorbid anxiety disorders, an attentional variable, and two planning variables makes it possible to correctly classify 82% of the depressed patients who responded to the treatment with fluoxetine, and 74% of the patients who did not respond to that treatment.

Major Depressive Disorder in recovery and neuropsychological functioning: effects of selective serotonin reuptake inhibitor and dual inhibitor depression treatments on residual cognitive deficits in patients with Major Depressive Disorder in recovery

INTRODUCTION

Cognitive disturbances in Major Depressive Disorder (MDD) could persist beyond the symptomatic phase of the illness. However, the works addressing this topic did not usually account for the possible impact of medication on the cognitive functions of depressed patients. The present study aims to investigate whether MDD patients in remission treated with selective serotonin reuptake inhibitors (SSRI) or dual serotonergic-noradrenergic reuptake inhibitors (SNRI) show cognitive deficits, to study whether the same patients suffer neuropsychological disturbances when they are unmedicated and in recovery phase, and if the previous pharmacological treatment used to achieve the remission of MDD clinical symptoms had any effect in the profile of these patients' cognitive performance in the recovery phase.

METHODS

Thirty-six subjects with MDD treated with escitalopram and 37 depressed patients with duloxetine were compared both in remission phase and 24 weeks later, when they were unmedicated and in recovery phase. They were also compared, in both moments, to 37 healthy subjects.

RESULTS

The control subjects showed a broader better cognitive performance than MDD patients in both measurement moments, but several cognitive functions improved over time. Also, the patients treated with SNRI performed better in memory tests than the SNRI-treated patients in remission phase, and in recovery phase.

LIMITATIONS

Our sample size is somewhat small, and we followed our patients only for 6months after treatment.

CONCLUSIONS

Cognitive functions improve over time in patients with MDD beyond the remission phase, and the antidepressant treatment class used in acute depressive phase could influence his/her memory improvement.

Decision-making impairments in women with binge eating disorder

Even though eating is frequently driven by overindulgence and reward rather than by energy balance, few studies so far have analyzed decision-making processes and disturbances in feedback processing in women with binge eating disorder (BED). In an experimental study, 17 women with BED (DSM-IV) and 18 overweight healthy controls (HC) were compared in the game of dice task (GDT). This task assesses decision-making under risk with explicit rules for gains and losses. Additionally, differences in dispositional activation of the behavior inhibition and behavior approach system as well as cognitive flexibility were measured. Main results revealed that women with BED make risky decisions significantly more often than HC. Moreover, they show impaired capacities to advantageously utilize feedback processing. Even though these deficits were not related to disease-specific variables, they may be important for the daily decision-making behavior of women with BED, thus being relevant as a maintenance factor for the disorder.

Decision-making in long-term cocaine users: Effects of a cash monetary contingency on Gambling task performance

BACKGROUND

The Iowa Gambling task, which typically incorporates hypothetical monetary earnings and losses for performance, has been widely used to measure decision-making in substance abusers. We examined the effects of a cash monetary contingency on Gambling task performance in cocaine abusers and control participants.

METHODS

Twenty-two long-term cocaine smokers who met DSM-IV criteria for cocaine dependence and 24 non-cocaine-using control participants completed this study. Both groups were similar in terms of age, executive function, and self-reported alcohol and marijuana use. All participants performed the Gambling task under two counterbalanced conditions: under one condition, earnings and losses were hypothetical, and under the other condition, earnings and losses were in cash.

RESULTS

Condition x group interactions on card selection and task completion time were noted (p<0.05). Under the hypothetical payment condition, cocaine abusers selected a greater proportion of cards from disadvantageous decks than advantageous decks (p<0.05), but took a similar amount of time to complete the task, relative to control participants. However, under the cash payment condition, no group differences were seen for card selection and cocaine abusers took more time than controls to complete the task (p<0.05).

CONCLUSIONS

The application of tangible consequences improved the decision-making and effort of cocaine abusers on the Gambling task, relative to control participants. These findings underscore the importance of considering population-specific factors (e.g., sensitivity to instructional vs. consequential control) when conducting neuropsychological research in substance abusers.

Executive performance of depressed suicide attempters: the role of suicidal ideation

OBJECTIVE

Suicidal ideation has been related to cognitive rigidity whereas suicidal behaviour itself was associated with specific executive deficits. Yet it remains unclear if a distinct cognitive suicidal phenotype does exist. The aim of the present study was to further investigate the role of suicidal thinking for the neuropsychological performance in depressive suicide attempters.

METHOD

Depressive inpatients after a recent suicide attempt, who either had present suicidal ideation (n=14) or not (n=15) and healthy controls (n=29) were recruited. The groups were assessed by means of executive tasks designed to capture impulsive decision-making, and with verbal memory and attention tests. Self-rating measures of impulsivity and aggression were further applied.

RESULTS

Only patients with current suicidal ideation showed executive dysfunctions with impaired decision-making being the most salient. Verbal memory and attention were reasonably intact in all patients. All patients reported increased aggression.

CONCLUSION

Suicidal ideation is clearly associated with impaired cognitive performance. Our results suggest that executive deficits seen in depressive suicide attempters have a state-dependent component.