Is there a valence-specific pattern in emotional conflict in major depressive disorder? An exploratory psychological study

Current oral contraceptive use affects explicit and implicit measures of depression in women

Some data suggest that increased depressive symptoms may occur in women using combined oral contraceptives (OCs). However, this idea is controversial and the existing evidence is conflicting. The present study compared negative affect in 53 healthy women (M age = 19.9 years) during intervals of active daily OC hormone intake and during the washout week of the contraceptive cycle when no exogenous estrogens or progestins are used. A prospective counterbalanced repeated-measures study design was employed. Depressive affect was evaluated using standard psychometric tests of explicit (self-perceived) and implicit negative affect. Implicit measures are considered less subject to bias related to social expectations, self-awareness, or willingness to disclose. Other than their usual OCs, participants were medication-free and had been using OCs for a median of 12 mo. We found that measures of implicit affect (e.g., Affect Misattribution Procedure, Emotional Stroop Test) displayed a more depressive-like pattern of performance during active hormone intake, particularly among a subgroup of OC users who reported experiencing high levels of depressive affect more generally. In contrast, participants' self-perceptions suggested that they perceived their negative symptoms to be greater during the 'off' phase of the OC cycle, when OC steroids are withdrawn and menses occurs. The present findings reinforce the possibility of depressive mood effects associated with OC usage, and highlight the utility of including implicit measures, but also illustrate the complexity of mood assessment in OC users.

Effects of Four Different EEG-Neurofeedback Reinforcement Types in Healthy Individuals - A Pilot Study

EEG neurofeedback (EEG-NFB) is a promising tool for the treatment of depressive disorders. However, many methods for the presentation of neurobiological reactions are available and it is widely unknown which of these feedback options are preferrable. Moreover, the influence of motivation on NFB training success is insufficiently studied. This study analyzed the efficacy of a novel EEG protocol (FC3/Pz) based on findings for NFB in depression. The role of four feedback options (Rumination, Anxiety, Meditation Master, Moving Art) from the NFB software "Brain Assistant" and motivation in EEG-based NFB performance was studied. Regarding "Anxiety" and "Rumination" visual feedback was used to evoke emotions; reinforcement (both negative and positive operant conditioning) was continuous. Regarding "Meditation Master" visual feedback was combined with continuous positive reinforcement. Regarding "Moving Art" 20-min calm nature films with neutral character were used; both visual and auditive feedback were applied. The reinforcement was positive and continuous. 13 healthy participants completed 15 EEG sessions over four months combining simultaneous frontal (aims: reduction of theta-, alpha- and high beta-activity, increase of low and mid beta-activity) and parietal training (aims: reduction of theta-, alpha 1-, mid and high beta-activity, increase of alpha 2- and low beta-activity). We observed significantly more pronounced percentage change in the expected direction for Anxiety than Moving Art (mean difference = 3.32; p = 0.003). The association between motivation and performance was non-significant. Based on these results we conclude that feedback with both negative and positive operant conditioning and emotion evoking effects should be preferred.

Differential effects of faces and words in cognitive control in older adults with and without major depressive disorder: An emotional Stroop task study

Aging and major depressive disorders have been associated with impaired cognitive control. These deficits are also influenced by the affective valence and by the type of stimulus processed. Using an emotional Stroop task, the current study aims to examine cognitive control deficits and their association with emotion regulation in depression and the influence of the type of stimulus (words and faces) in this association. A total of 26 older patients with a major depressive disorder (MDD) (19 women; age range: 65-84 years) and 26 older healthy controls (18 women; age range: 65-80 years) participated in the study. The results showed that MDD individuals presented greater Stroop effects than their healthy controls and an absence of the conflict adaptation effect defined as a reduction of the influence of irrelevant stimulus dimensions after incongruent trials. Additionally, our results also showed that the processing of emotional words in depressed participants is more automatic than the processing of emotional faces. These findings suggest that older depressed individuals have greater difficulty in recognizing affective facial expressions than older healthy controls, while the over-learned behavior of word reading greatly reduces differences in the performance of the emotional Stroop task between groups (MDD and healthy controls).

It is not always positive: emotional bias in young and older adults

Healthy ageing has been associated with a bias toward positive information and greater psychological well-being. However, to what extent this positivity bias also applies to prioritizing positive information under emotional competition is unclear. Old and young adults performed a word-face interference task, in which they responded to the valence of positive and negative target-words while ignoring happy or angry distractor-faces that could be affectively congruent or incongruent. A control condition with scrambled neutral distractor-faces was also used. Findings showed small facilitation effects with faster responses when targets and distractors were affectively congruent and large interference effects with slower responses when targets and distractors were affectively incongruent compared to the control condition. Importantly, whereas for younger adults there was a similar pattern of interference from happy and angry distractor-faces, for older adults there was greater interference from angry distractor-faces. The present findings are discussed in the context of emotional bias literature.

Subgenual Cingulum Microstructure Supports Control of Emotional Conflict

Major depressive disorder (MDD) is associated with specific difficulties in attentional disengagement from negatively valenced material. Diffusion MRI studies have demonstrated altered white matter microstructure in the subgenual cingulum bundle (CB) in individuals with MDD, though the functional significance of these alterations has not been examined formally. This study explored whether individual differences in selective attention to negatively valenced stimuli are related to interindividual differences in subgenual CB microstructure. Forty-six individuals (21 with remitted MDD, 25 never depressed) completed an emotional Stroop task, using happy and angry distractor faces overlaid by pleasant or unpleasant target words and a control gender-based Stroop task. CBs were reconstructed in 38 individuals using diffusion-weighted imaging and tractography, and mean fractional anisotropy (FA) computed for the subgenual, retrosplenial, and parahippocampal subdivisions. No significant correlations were found between FA and performance in the control gender-based Stroop task in any CB region. However, the degree of interference produced by angry face distractors on time to identify pleasant words (emotional conflict) correlated selectively with FA in the subgenual CB (r = -0.53; P = 0.01). Higher FA was associated with reduced interference, irrespective of a diagnosis of MDD, suggesting that subgenual CB microstructure is functionally relevant for regulating attentional bias toward negative interpersonal stimuli.

Valence-based Word-Face Stroop task reveals differential emotional interference in patients with major depression

Word-Face Stroop task creates emotional conflict between affective words and affective faces. In this task, healthy participants consistently slow down while responding to incongruent cases. Such interference related slowdown is associated with recruitment of inhibitory processes to eliminate task-irrelevant information. We created a valence-based Word-Face Stroop task, in which participants were asked to indicate whether the words in the foreground are positive, negative or neutral. Healthy participants were faster and more accurate than un-medicated patients with major depression disorder (MDD). In addition, a significant congruence by group interaction is observed: healthy participants slowed down for incongruent cases, but MDD patients did not. Furthermore, for the negative words, healthy individuals made more errors while responding to incongruent cases but MDD patients made the lowest number of errors for this category. The emotional percepts of the patients were intact, because correct response rates in word valence judgments for positive/negative words, and reaction times for happy/sad faces had similar patterns with those of controls. These findings are supported by the analytical rumination interpretation of depression: patients lose speed/accuracy in laboratory tasks due to processing load spent during continuous rumination. However, for tasks in line with their preoccupation, continual practice makes the patients more vigilant and adept.

Audiovisual emotional processing and neurocognitive functioning in patients with depression

Alterations in the processing of emotional stimuli (e.g., facial expressions, prosody, music) have repeatedly been reported in patients with major depression. Such impairments may result from the likewise prevalent executive deficits in these patients. However, studies investigating this relationship are rare. Moreover, most studies to date have only assessed impairments in unimodal emotional processing, whereas in real life, emotions are primarily conveyed through more than just one sensory channel. The current study therefore aimed at investigating multi-modal emotional processing in patients with depression and to assess the relationship between emotional and neurocognitive impairments. Fourty one patients suffering from major depression and 41 never-depressed healthy controls participated in an audiovisual (faces-sounds) emotional integration paradigm as well as a neurocognitive test battery. Our results showed that depressed patients were specifically impaired in the processing of positive auditory stimuli as they rated faces significantly more fearful when presented with happy than with neutral sounds. Such an effect was absent in controls. Findings in emotional processing in patients did not correlate with Beck's depression inventory score. Furthermore, neurocognitive findings revealed significant group differences for two of the tests. The effects found in audiovisual emotional processing, however, did not correlate with performance in the neurocognitive tests. In summary, our results underline the diversity of impairments going along with depression and indicate that deficits found for unimodal emotional processing cannot trivially be generalized to deficits in a multi-modal setting. The mechanisms of impairments therefore might be far more complex than previously thought. Our findings furthermore contradict the assumption that emotional processing deficits in major depression are associated with impaired attention or inhibitory functioning.

Crossmodal emotional integration in major depression

Major depression goes along with affective and social-cognitive deficits. Most research on affective deficits in depression has, however, only focused on unimodal emotion processing, whereas in daily life, emotional perception is often highly dependent on the evaluation of multimodal inputs. We thus investigated emotional audiovisual integration in patients with depression and healthy subjects. Subjects rated the expression of happy, neutral and fearful faces while concurrently being exposed to emotional or neutral sounds. Results demonstrated group differences in left inferior frontal gyrus and inferior parietal cortex when comparing incongruent to congruent happy facial conditions, mainly due to a failure of patients to deactivate these regions in response to congruent stimulus pairs. Moreover, healthy subjects decreased activation in right posterior superior temporal gyrus/sulcus and midcingulate cortex when an emotional stimulus was paired with a neutral rather than another emotional one. In contrast, patients did not show such deactivation when neutral stimuli were integrated. These results demonstrate aberrant neural response in audiovisual processing in depression, indicated by failure to deactivate regions involved in inhibition and salience processing when congruent and neutral audiovisual stimuli pairs are integrated, providing a possible mechanism of constant arousal and readiness to act in this patient group.

Emotional conflict in a model modulates nociceptive processing in an onlooker: a laser-evoked potentials study

Observing models displaying facial expressions of pain elicits neural activity in onlookers' neural structures involved in first-hand experience of pain and in monitoring conflicting information. We investigated whether the purported conflict between the pain and its emotional expression in a model modulates cortical responses elicited by nociceptive laser stimuli in an onlooker. Seeing happy facial expressions, incongruent with the perceptual status attributed to the model, determined a significant reduction in the laser-evoked N2 potential. One of the main sources of this response is the anterior cingulate cortex, an area involved in pain perception, empathy for pain and conflict detection. A pre-activation of the anterior cingulate cortex due to the detection of the emotional conflict may, therefore, be responsible for the reduction of nociceptive-related response in the same brain area. Thus, top-down variables, like the appraisal of the others' emotional status, modulate onlookers' nociceptive-related neural activity.