Frontal brain asymmetry in depression with comorbid anxiety: a neuropsychological investigation

The approach-withdrawal model posits that depression and anxiety are associated with a relative right asymmetry in frontal brain activity. Most studies have tested this model using measures of cortical brain activity such as electroencephalography. However, neuropsychological tasks that differentially use left versus right frontal cortical regions can also be used to test hypotheses from the model. In two independent samples (Study 1 and 2), the present study investigated the performance of currently depressed individuals with or without a comorbid anxiety disorder and healthy controls on neuropsychological tasks tapping primarily left (verbal fluency) or right (design fluency) frontal brain regions. Across both samples, results indicated that comorbid participants performed more poorly than depressed only and control participants on design fluency, while all groups showed equivalent performance on verbal fluency. Moreover, comorbid participants showed "asymmetrical" performance on these two tasks (i.e., poorer design [right frontal] relative to verbal [left frontal] fluency), whereas depressed only and control participants showed approximately symmetrical profiles of performance. Results from these two samples suggest an abnormal frontal asymmetry in neurocognitive performance driven primarily by right frontal dysfunction among anxious-depressed individuals and highlight the importance of considering comorbid anxiety when examining frontal brain functioning in depression.     

Stress reactivity and coping in seasonal and nonseasonal depression

Stress, stress reactivity, and coping skill use were examined in individuals with seasonal depression, nonseasonal depression, and nondepressed controls. Although participants in the two depressed groups reported using more avoidance coping strategies than controls, only participants in the seasonal depressed group reported using more season-specific coping (i.e., light-related strategies) than participants in the nonseasonal depressed and control groups. Individuals in the seasonal depressed group also reporting using acceptance coping strategies less frequently than individuals in the control group. Only participants in the nonseasonal depressed group, however, exhibited greater psychophysiological arousal in reaction to a laboratory stressor (i.e., unsolvable anagram task) when compared to participants in the seasonal and nondepressed control groups. Participants in both depressed groups reported greater impact of negative life events during the past 6 months than did controls. Similarities and differences in the two types of depression may have implications for the conceptualization and treatment of seasonal depression.     

The relation between electroencephalogram asymmetry and attention biases to threat at baseline and under stress

Electroencephalogram (EEG) asymmetry in the alpha frequency band has been implicated in emotion processing and broad approach-withdrawal motivation systems. Questions remain regarding the cognitive mechanisms that may help elucidate the observed links between EEG asymmetry and patterns of socioemotional functioning. The current study observed frontal EEG asymmetry patterns at rest and under social threat among young adults (N = 45, M = 21.1 years). Asymmetries were, in turn, associated with performance on an emotion-face dot-probe attention bias task. Attention biases to threat have been implicated as potential causal mechanisms in anxiety and social withdrawal. Frontal EEG asymmetry at baseline did not predict attention bias patterns to angry or happy faces. However, increases in right frontal alpha asymmetry from baseline to the stressful speech condition were associated with vigilance to angry faces and avoidance of happy faces. The findings may reflect individual differences in the pattern of response (approach or withdrawal) with the introduction of a mild stressor. Comparison analyses with frontal beta asymmetry and parietal alpha asymmetry did not find similar patterns. Thus, the data may reflect the unique role of frontal regions, particularly the dorsolateral prefrontal cortex, in cognitive control and threat detection, coupled with ruminative processes associated with alpha activity.     

Regional brain electrical asymmetries discriminate between previously depressed and healthy control subjects

Baseline resting electroencephalogram (EEG) activity was recorded from 6 normothymic depressives and 8 controls using three different reference montages. Power in all frequency bands was extracted by Fourier transformation. Significant Group X Region X Hemisphere interactions were found consistently for alpha band power only. Previously depressed subjects had less left-sided anterior and less right-sided posterior activation (i.e., more alpha activity) than did never depressed subjects. Previously depressed subjects had no history of pharmacological treatment and did not differ from controls in emotional state at the time of testing. The pattern of anterior and posterior asymmetry in the previously depressed subjects is similar to that found in acutely depressed subjects and suggests that this may be a state-independent marker for depression.     

Cognitive vulnerability and frontal brain asymmetry: common predictors of first prospective depressive episode

The hopelessness theory of depression proposes that individuals with a depressogenic cognitive style are more likely to become hopeless and experience depression following negative life events. Although the neurophysiological underpinnings of cognitive style remain speculative, research indicates that decreased relative left frontal brain electrical activity holds promise as a traitlike marker of depression. This begs the question: Do measures of depressogenic cognitive style and resting frontal brain asymmetry index a common vulnerability? The present study provides preliminary support for this hypothesis. At baseline assessment, increased cognitive vulnerability to depression was associated with decreased relative left frontal brain activity at rest in individuals with no prior history of, or current, depression. Following baseline assessment, participants were followed prospectively an average of 3 years with structured diagnostic interviews at 4-month intervals. Both cognitive vulnerability and asymmetric frontal cortical activity prospectively predicted onset of first depressive episode in separate univariate analyses. Furthermore, multivariate analyses indicated that cognitive vulnerability and frontal asymmetry represented shared, rather than independent, predictors of first depression onset.     

Left frontal hypoactivation in depression.

Baseline resting electroencephalogram activity was recorded with 3 different reference montages from 15 clinically depressed and 13 control subjects. Power in all frequency bands was extracted by fast Fourier transformation. There was a significant Group X Hemisphere interaction in the mid-frontal region, for the alpha band power only. Depressed subjects had less left-sided activation (i.e., more alpha activity) than did normal control subjects. This pattern of diminished left-sided frontal activation is interpreted as indicating a deficit in approach mechanisms in depressed subjects.     

Postnatal maternal symptoms of depression and child emotion dysregulation: The mediation role of infant EEG alpha asymmetry

In a community-based sample of 104 infants and their mothers, we hypothesized a pathway from postnatal maternal symptoms of depression to child emotion dysregulation, and tested at 6 months of age the mediation role of alpha asymmetry at frontal and parietal sites. We recorded infant resting-state EEG at 6 months of age. Child emotion dysregulation was measured at 24 months by the Child Behavior Checklist Dysregulation Profile derived from the CBCL 1½-5. Maternal depression symptoms were scored 6 months after the delivery by the Anxious/Depressed scale of the Adult Self-Report. We used structural equation modeling to test the mediation model from maternal depression symptoms to child emotion dysregulation mediated by frontal and parietal alpha asymmetry. The mediation model provided an excellent fit to the data [χ2(3) = 3.088, p = .378; RMSEA = .017, CFI = .1.00; SRMR = 0.040] and explained 23.3% of the variance in child emotion dysregulation. The indirect path via parietal alpha asymmetry was significant (β = .065; SE = .033; 95% CI = .001–.139; p = .048), i.e. greater levels of maternal depression symptoms predicted left parietal alpha asymmetry, which predicted higher levels of child emotion dysregulation. The direct effect, i.e. the pathway linking maternal depression symptoms and child emotion dysregulation above and beyond the indirect effects, was also significant. We found evidence for a partial mediation role of left parietal alpha asymmetry in a longitudinal pathway from postnatal maternal symptoms of depression to child emotion dysregulation, providing support for left parietal asymmetry as an index of biological vulnerability to emotion dysregulation in the first years of life.     

抑郁症人群的心境一致性认知偏向

心境一致性认知偏向指的是抑郁病人的认知加工偏向负性情绪效价, 简称认知偏向。大量行为学、电生理学以及脑成像学的研究显示该认知偏向主要包括知觉偏向、注意偏向、记忆偏向以及解释偏向。该认知偏向以加工偏向负性、积极偏向缺失以及认知控制受损为特点, 且是杏仁核等边缘系统对负性信息过度激活、纹状体对正性信息激活不足以及额区激活模式异常三个相应脑机制协同作用的产物。目前此领域存在各认知偏向之间联系不清楚、认知偏向和抑郁症的因果关系难以确定以及各研究结果不一致等有待回答的问题, 这些重要问题值得引起该领域未来研究者的注意。     

Psychophysiological Identification of Depression Subtypes in Older Adults: Problematic Diagnostic Heterogeneity in the DSM-III-R and DSM-IV

The DSM-IV does not subclassify patients with depression on the basis of anxiety level. Hence a significant confound may exist in all outcome studies that employ DSM definitions of depression. To establish that objectively identifiable anxious and nonanxious subtypes of depression do indeed exist, a psychophysiological assessment battery was used with 114 treatment-seeking older adults. Dichotomous criterion categorization as either Nonanxious Depressed or Anxious Depressed was based on (a) DSM-III-R/DSM-IV diagnosis, and (b) standardized questionnaires of psychopathology. Multivariate analyses revealed no differences between groups when DSM criteria were used to classify participants. However, identical analyses using phenomenological diagnostic criteria indicated that anxious and nonanxious depressed participants differed in their psychophysiological response to negative imagery. Although anxious and nonanxious depressed participants evince different psychophysiological response patterns, these differences unfortunately are obscured by the DSM. Consequently, a phenomenological classification system may be more appropriate with affective disorders.     

Adaptive social reasoning in depressed mood and depressive vulnerability

In this study we evaluate the evolutionary hypothesis that depressed states are associated with more adaptive reasoning about social risks, such as defeat or rejection. A total of 78 women were administered one of two mood inductions (depressed vs. neutral), followed by four Wason selection reasoning tasks (truth-detection, cheater-detection, and two social risk tasks addressing attachment and social competition risks). Those in the depressed mood condition gave significantly more correct responses on a task requiring participants to reason about social competition. There were no significant differences on performance for the other reasoning tasks between the two mood induction conditions. Furthermore, measures of two dimensions of depression prone personality (sociotropy and autonomy) were associated with less adaptive reasoning about social risks. These results suggest that mildly depressed states may indeed facilitate adaptive reasoning within certain domains, whereas vulnerability to depression may be associated with a relative impairment in reasoning about social risks.     

抑郁症状中学生自我相关生活事件的回忆、再认和启动效应特点

采用Tversky的实验设计,对非抑郁和抑郁症状中学生的回忆、再认和启动效应进行了探讨。实验发现,抑郁症状中学生对自我相关生活事件信息加工存在负性回忆、负性再认、负性启动和负性加工偏向;抑郁症状中学生对自我相关生活事件信息加工的回忆具有情境一致性;对再认材料的不同加工深度影响抑郁症状中学生自我相关生活事件信息加工的再认;抑郁症状中学生对自我相关生活事件信息加工的负性启动主要是由于对负性条目、中性条目的负性偏向加工引起     

Frontal Brain Asymmetry and Depression: A Self-regulatory Perspective

Recent findings indicate that frontal brain asymmetry may be a marker of for depression. However, the psychological predispositions that account linkage between frontal brain asymmetry and depression are unclear. approach-withdrawal hypothesis is the primary framework that has been to account for the linkages between frontal brain asymmetry and or emotional disorders. We review evidence consistent with this and suggest several directions for its extension. One such direction is to constrain the approach-withdrawal hypothesis by linking frontal asymmetry to the known functions of the prefrontal cortex. On this we propose that frontal brain asymmetry may be preferentially linked processes that promote the temporal continuity and shifting of or emotional priorities and the suppression of interference by sources of motivation or emotion. We review evidence from and neurobiological studies of depression that is broadly consistent with these predictions. We emphasise the need for future studies testing our hypotheses.     

Putative EEG measures of social anxiety: Comparing frontal alpha asymmetry and delta–beta cross-frequency correlation

The goal of the present study was to examine whether frontal alpha asymmetry and delta–beta cross-frequency correlation during resting state, anticipation, and recovery are electroencephalographic (EEG) measures of social anxiety. For the first time, we jointly examined frontal alpha asymmetry and delta–beta correlation during resting state and during a social performance task in high (HSA) versus low (LSA) socially anxious females. Participants performed a social performance task in which they first watched and evaluated a video of a peer, and then prepared their own speech. They believed that their speech would be videotaped and evaluated by a peer. We found that HSA participants showed significant negative delta–beta correlation as compared to LSA participants during both anticipation of and recovery from the stressful social situation. This negative delta–beta correlation might reflect increased activity in subcortical brain regions and decreased activity in cortical brain regions. As we hypothesized, no group differences in delta–beta correlation were found during the resting state. This could indicate that a certain level of stress is needed to find EEG measures of social anxiety. As for frontal alpha asymmetry, we did not find any group differences. The present frontal alpha asymmetry results are discussed in relation to the evident inconsistencies in the frontal alpha asymmetry literature. Together, our results suggest that delta–beta correlation is a putative EEG measure of social anxiety.     

Emotion regulation in depression: Examining the role of cognitive processes

Sustained negative affect is a hallmark feature of depressive episodes. The ability to regulate emotional responses to negative events may therefore play a critical role in our understanding of this debilitating disorder. Individual differences in cognitive processes such as attention, memory, and interpretation may underlie difficulties in emotion regulation and numerous studies have identified cognitive biases and deficits that characterise depressed people. Few studies, however, have explicitly linked these biases to the difficulties in emotion regulation that are associated with depression. In this paper we discuss relations among cognitive processes and emotion regulation and review the depression literature to identify cognitive biases and deficits that may underlie maladaptive responses to negative events and mood states. Our review suggests that difficulties in the disengagement from negative material, memory biases, and deficits in cognitive control are frequently observed in depressive disorders and may be associated with the use of maladaptive emotion regulation strategies, such as rumination. These biases may also be related to difficulties implementing strategies that are effective for non-depressed people, such as recall of mood-incongruent material and reappraisal. Our review also suggests, however, that empirical studies linking cognitive biases and emotion regulation in depression are still largely missing and would present an important goal for future research in this area.     

Cognitive,affective and social mechanisms in depression risk: Cognition,hostility, and coping style

Although some research has assessed cognitive variables in individuals at risk for depression, few studies have specifically assessed the role of automatic thinking, and virtually no studies have assessed anger and coping in this group. The current study compared measures of these variables in a high-risk group that was defined on the basis of a previous episode of depression, and a control group comprised of low-risk/never depressed individuals. Even though neither group evidenced depressive symptoms at the time of assessment, group comparisons and regression analyses indicated that high-risk individuals reported more negative automatic thoughts than did low-risk participants and that social support seeking, self-blame, and avoidance emerged as coping predictors of risk as did higher levels of anger and hostility. These data thus suggest patterns of interpersonal, behavioural, and cognitive variables that may characterise depression risk.     

Cognitive Vulnerability to Persistent Depression

Abstract

The account of cognitive vulnerability to depression offered by Beck's cognitive model is summarised. As this account currently lacks consistent empirical support, an alternative, related, account is presented. This proposes that, once a person is initially depressed, an important factor that determines whether their depression remains mild or transient, or becomes more severe and persistent, is the nature of the negative cognitive processes and constructs that become active and accessible in the depressed state. These interact with the nature of environmental difficulties, available social support, and biological factors, to determine whether a depression-maintaining cognitive-affective vicious cycle will be set up.

Results from studies specifically designed to test predictions from this account have yielded positive results. Findings consistent with the hypothesis have also been obtained in other prospective studies which have shown that cognitive measures, administered in the depressed state, predict the future course of depression independently of initial levels of depression.

The hypothesis is elaborated to incorporate the demonstrated relationship of elevated neuroticism to risk and persistence of depression. Recent views on the nature of sex differences in rates of depression, and on the relationship of attributional style to depression are also compatible with the hypothesis. It is concluded that the hypothesis has encouraging preliminary support.

SUMMARY

Two broad aspects of cognitive vulnerability to depression can be distinguished. The first is the tendency to evaluate certain types of life event in ways which will produce intense rather than mild depression. This is the aspect of vulnerability on which Beck's cognitive model appears to concentrate. There are considerable difficulties in assessing this aspect of Beck's model and it is not consistently supported by comparison of recovered depressed patients with control groups.

The second aspect of cognitive vulnerability relates to the cognitive processes and constructs that become active and accessible once a person is in a state of depression. Within this approach, vulnerability to onset and vulnerability to persistence of depression can be roughly distinguished, depending on whether the focus is on the period when the depression has been present for only a brief period, or is mild, or whether depression has already existed for some time and reached at least moderate severity. The account presented here proposes that a crucial factor determining whether an initially mild or transient depressed state remains mild or soon disappears, or becomes more severe and persistent, is whether a vicious cycle based on a reciprocally reinforcing relationship between depressed mood and negative cognitive processing can become established. The probability that this cycle will become established is, in turn, a function of a complex interaction between the environmental difficulties facing a person, the support available to them, their biological state, and the nature of the cognitive processes and constructs that are active and accessible in the depressed state. The kind of cognitive process and constructs that are most active and accessible in the depressed state will be a function both of the patterns of cognitive processing that are characteristic of the person in their normal mood state (such as those related to neuroticism), and of the patterns of cognitive processing that become active in the depressed state. It is on these latter that the differential activation hypothesis concentrates. It suggests that individual differences in the cognitive processes and constructs that become active and accessible in the depressed' state can make an important contribution to whether an initial state of depression becomes more intense, or fades away, and whether, once established, depression of moderate severity persists a long time or a short time. In particular, it is proposed that processes and constructs related to global negative characterological evaluations of the self or that, in other ways, lead to interpretations of experience as highly aversive and uncontrollable are likely to act to intensify and maintain depression.

Two investigations specifically designed to test predictions from the differential activation hypothesis yielded positive results. Further supportive evidence is available from a number of other studies which have examined the relationship between cognitive measures, administered in the depressed state, and the future course of depression. Such studies haverecurringly found that persistence or return of depression is associated with initially high scores on measures of negative cognition, and this association remains when the effects of initial depression level are partialled out.

In addition to this encouraging preliminary empirical support, the differential activation hypothesis has the further attraction that it can incorporate into this account the well established finding that neuroticism is associated with risk of becoming depressed, and of depression persisting. Further, it is quite consistent with recent proposals related to sex differences in rates of depression, and to the relationship of attributional style to depression.     

Création de l’Échelle de Distorsions Cognitives pour adultes (EDC-A) : étude des propriétés psychométriques en population générale et association avec l’anxiété et la dépression

IntroductionCognitive distortions contribute to the maintenance of inappropriate cognitive schemas and play a role in the emergence of pathologies such as anxiety and depression. We developed the Cognitive Distortion Scale for Adults in order to identify distortions in individuals’ reasoning. The main objectives of this study were: (1) to study the psychometric properties of the Cognitive Distortion Scale for Adults, (2) to identify cognitive distortions associated with anxiety and depression in the general population.MethodThe study involved 916 participants (151 men and 765 women) aged 18 to 85-years. The participants completed the Cognitive Distortion Scale for Adults. The tool presents 42 mini scenarios with a daily life situation and a proposition concerning a cognitive distortion. Participants must give their degree of agreement (0 to 10) with this one. Seven cognitive distortions are operationalized (dichotomous reasoning, disqualification of one of the poles, arbitrary focusing, omission of the neutral, requalification in the other pole, maximization and minimization). They also completed the Hospital Anxiety and Depression Scale. Both scales were available online on the Internet. The total duration of the test was approximately 10 minutes. A group of 35 participants completed the two scale 15 days apart.ResultsThe sub-dimensions of EDC-A obtain Cronbach alphas higher than .65 and EDC-A has a coherent factor structure. The scale has good temporal stability. Anxiety is predicted by dichotomous reasoning, disqualification of one of the poles, arbitrary focusing and maximization. Depression is predicted by dichotomous reasoning, arbitrary focusing, omission of the neutral and requalification in the other pole. Anxiety and depression are associated with negative cognitive distortions in reasoning. However, depression is also associated with positive cognitive distortions. Subjects with depression produce more varied cognitive distortions than subjects with anxiety.DiscussionThe Cognitive Distortion Scale for Adults shows promising psychometric properties. Further studies will need to be conducted to confirm these results. Anxiety would be related to biased information treatment of negative information, whereas depression would be related to more comprehensive biased information treatment, both negative and positive information. Anxiety would be related to suboptimal functioning of reasoning abilities; depression would be more characterized by a structural deficit of reasoning abilities.     

Reward sensitivity in depression: a biobehavioral study

The approach-withdrawal model posits 2 neural systems of motivation and emotion and hypothesizes that these systems are responsible for individual differences in emotional reactivity, or affective styles. The model also proposes that depression is characterized by a deficit in reward-seeking behavior (i.e., approach motivation) and is associated with a relative decrease in left frontal brain activity. The authors tested aspects of this model by comparing the electroencephalogram alpha power of depressed and nondepressed individuals during a task that manipulated approach motivation. The study found that control participants and individuals with late-onset depression exhibited the hypothesized increase in left frontal activity during the approach task but individuals with early-onset depression did not. This suggests that early-onset depression may be associated with a deficit in the hypothesized approach motivation system.     

PTSD arousal and depression symptoms associated with increased right-sided parietal EEG asymmetry

Researchers have proposed that depression and particular types of anxiety are associated with unique patterns of regional brain activation. The authors examined the relationship among posttraumatic stress disorder (PTSD), anxiety, and depressive symptoms and frontal, temporal, and parietal EEG alpha asymmetry in female Vietnam War nurse veterans. The results indicate that PTSD arousal symptoms are associated with increased right-sided parietal activation. However, the combination of arousal, depression, and their interaction explain more than twice the variance in parietal asymmetry compared with arousal alone. The results support the contention that the association between anxiety and right-sided posterior activation is specific to the anxious arousal subtype. These findings underscore the importance of isolating, both theoretically and statistically, emotional subcomponents in studies of regional brain activation.     

Frontal brain asymmetry and reward responsiveness: a source-localization study

The influence of approach and avoidance tendencies on affect, reasoning, and behavior has attracted substantial interest from researchers across various areas of psychology. Currently, frontal electroencephalographic (EEG) asymmetry in favor of left prefrontal regions is assumed to reflect the propensity to respond with approach-related tendencies. To test this hypothesis, we recorded resting EEG in 18 subjects, who separately performed a verbal memory task under three incentive conditions (neutral, reward, and punishment). Using a source-localization technique, we found that higher task-independent alpha2 (10.5-12 Hz) activity within left dorsolateral prefrontal and medial orbitofrontal regions was associated with stronger bias to respond to reward-related cues. Left prefrontal resting activity accounted for 54.8% of the variance in reward bias. These findings not only confirm that frontal EEG asymmetry modulates the propensity to engage in appetitively motivated behavior, but also provide anatomical details about the underlying brain systems.