Depression is associated with increased vagal withdrawal during unpleasant emotional imagery after cardiac surgery

Approaches to studying emotion using physiological responses to spoken narratives: A scoping review

Narratives are effective tools for evoking emotions, and physiological measurements provide a means of objectively assessing emotional reactions - making them a potentially powerful pair of tools for studying emotional processes. However, extent research combining emotional narratives and physiological measurement varies widely in design and application, making it challenging to identify previous work, consolidate findings, and design effective experiments. Our scoping review explores the use of auditory emotional narratives and physiological measures in research, examining paradigms, study populations, and represented emotions. Following the PRISMA-ScR Checklist, we searched five databases for peer-reviewed experimental studies that used spoken narratives to induce emotion and reported autonomic physiological measures. Among 3466 titles screened and 653 articles reviewed, 110 studies were included. Our exploration revealed a variety of applications and experimental paradigms; emotional narratives paired with physiological measures have been used to study diverse topics and populations, including neurotypical and clinical groups. Although incomparable designs and sometimes contradictory results precluded general recommendations as regards which physiological measures to use when designing new studies, as a whole, the body of work suggests that these tools can be valuable to study emotions. Our review offers an overview of research employing narratives and physiological measures for emotion study, and highlights weaknesses in reporting practices and gaps in our knowledge concerning the robustness and specificity of physiological measures as indices of emotion. We discuss study design considerations and transparent reporting, to facilitate future using emotional narratives and physiological measures in studying emotions.

Brain-heart interaction disruption in major depressive disorder: disturbed rhythm modulation of the cardiac cycle on brain transient theta bursts

Brain neurons support arousal and cognitive activity in the form of spectral transient bursts and cooperate with the peripheral nervous system to adapt to the surrounding environment. However, the temporal dynamics of brain-heart interactions have not been confirmed, and the mechanism of brain-heart interactions in major depressive disorder (MDD) remains unclear. This study aimed to provide direct evidence for brain-heart synchronization in temporal dynamics and clarify the mechanism of brain-heart interaction disruption in MDD. Eight-minute resting-state (closed eyes) electroencephalograph and electrocardiogram signals were acquired simultaneously. The Jaccard index (JI) was used to measure the temporal synchronization between cortical theta transient bursts and cardiac cycle activity (diastole and systole) in 90 MDD patients and 44 healthy controls (HCs) at rest. The deviation JI was used to reflect the equilibrium of brain activity between diastole and systole. The results showed that the diastole JI was higher than the systole JI in both the HC and MDD groups; compared to HCs, the deviation JI attenuated at F4, F6, FC2, and FC4 in the MDD patients. The eccentric deviation JI was negatively correlated with the despair factor scores of the HAMD, and after 4 weeks of antidepressant treatment, the eccentric deviation JI was positively correlated with the despair factor scores of the HAMD. It was concluded that brain-heart synchronization existed in the theta band in healthy individuals and that disturbed rhythm modulation of the cardiac cycle on brain transient theta bursts at right frontoparietal sites led to brain-heart interaction disruption in MDD.

The pathophysiology and management of depression in cardiac surgery patients

Background

Depression is common in the cardiac surgery population. This contemporary narrative review aims to explore the main pathophysiological disturbances underpinning depression specifically within the cardiac surgery population. The common non-pharmacological and pharmacological management strategies used to manage depression within the cardiac surgery patient population are also explored.

Methods

A total of 1291 articles were identified through Ovid Medline and Embase. The findings from 39 studies were included for qualitative analysis in this narrative review.

Results

Depression is associated with several pathophysiological and behavioral factors which increase the likelihood of developing coronary heart disease which may ultimately require surgical intervention. The main pathophysiological factors contributing to depression are well characterized and include autonomic nervous system dysregulation, excessive inflammation and disruption of the hypothalamic-pituitary-adrenal axis. There are also several behavioral factors in depressed patients associated with the development of coronary heart disease including poor diet, insufficient exercise, poor compliance with medications and reduced adherence to cardiac rehabilitation. The common preventative and management modalities used for depression following cardiac surgery include preoperative and peri-operative education, cardiac rehabilitation, cognitive behavioral therapy, religion/prayer/spirituality, biobehavioral feedback, anti-depressant medications, and statins.

Conclusion

This contemporary review explores the pathophysiological mechanisms leading to depression following cardiac surgery and the current management modalities. Further studies on the preventative and management strategies for postoperative depression in the cardiac surgery patient population are warranted.

Impairments in episodic future thinking for positive events and anticipatory pleasure in major depression

BACKGROUND

Characteristic of the cardinal symptom of anhedonia, people with clinical depression report lower levels of anticipatory pleasure. However, the psychological mechanisms underlying these deficits are poorly understood. This is the first study to assess whether, and to what extent, phenomenological characteristics of episodic future thinking for positive future events are associated with anticipatory pleasure among depressed individuals.

METHODS

Individuals with a Major Depressive Episode (MDE; N = 117) and without (N = 47) completed ratings scales for depressive symptoms and trait anticipatory and consummatory pleasure. They then provided descriptions of personally-relevant positive future events and rated them for phenomenological characteristics and state anticipatory pleasure.

RESULTS

Between-groups analysis showed that those with MDE reported lower trait anticipatory and consummatory pleasure. They also simulated future events with less specificity, less detail/vividness, less use of mental imagery, less use of first-person perspective, less plausibility/perceived likelihood of occurring, and reported less associated state anticipatory pleasure. In regression analyses in the depressed group, lower scores for detail/vividness, mental imagery, and personal significance all uniquely predicted lower state anticipatory pleasure.

LIMITATIONS

Cognitive functioning was not assessed, which may help clarify deficits that underpin these findings. History of previous depressive episodes in the comparison group were not assessed, which may mean the observed between-group effects are underestimated.

CONCLUSIONS

This study provides further evidence of deficits in episodic future thinking and anticipatory pleasure in depressed individuals. It also establishes links between particular characteristics of episodic future thinking and state anticipatory pleasure, and indicates cognitive targets that may be amenable to intervention in order to reduce anhedonia.

The vividness of imagining emotional feelings in positive situations is attenuated in non-clinical dysphoria and predicts the experience of positive emotional feelings

OBJECTIVE

The vividness of imagining emotional feelings in positive situations (EFP) in non-clinically dysphoric and non-dysphoric individuals and its relation to dysphoric and positive feelings was examined.

METHOD

Participants were university students in Study 1 (N = 106, 84 women; 18-45 years), in Study 2 (N = 43, 39 women; 20-47 years), in Study 3 (N = 109, 92 women; 18-50 years) who filled out a set of questionnaires assessing depressive symptoms, cognition measures, and then completed an affective imagery task, using a cross-sectional design.

RESULTS

Non-clinically dysphoric participants imagined less vividly EFP than non-dysphoric participants. The vividness of imagining EFP accounted for group differences in positive feelings beyond positive and negative cognition and negative mood.

CONCLUSIONS

In addition to deficits in the general imagery of positive events, the attenuation of vividness of EFP in non-clinical dysphoric individuals warrants attention as a separate pathway by which non-clinically dysphoric individuals develop deficiencies of conscious positive feelings.

Mental Imagery in Depression: Phenomenology, Potential Mechanisms, and Treatment Implications

Mental imagery is an experience like perception in the absence of a percept. It is a ubiquitous feature of human cognition, yet it has been relatively neglected in the etiology, maintenance, and treatment of depression. Imagery abnormalities in depression include an excess of intrusive negative mental imagery; impoverished positive imagery; bias for observer perspective imagery; and overgeneral memory, in which specific imagery is lacking. We consider the contribution of imagery dysfunctions to depressive psychopathology and implications for cognitive behavioral interventions. Treatment advances capitalizing on the representational format of imagery (as opposed to its content) are reviewed, including imagery rescripting, positive imagery generation, and memory specificity training. Consideration of mental imagery can contribute to clinical assessment and imagery-focused psychological therapeutic techniques and promote investigation of underlying mechanisms for treatment innovation. Research into mental imagery in depression is at an early stage. Work that bridges clinical psychology and neuroscience in the investigation of imagery-related mechanisms is recommended.

Somatic, but not cognitive-affective, symptoms are associated with reduced heart rate variability in individuals with dysphoria

Background: Somatic, but not cognitive–affective, symptoms of depression have been associated with reduced heart rate variability (HRV), and with poor prognosis in cardiovascular patients. However, factors concomitant with cardiovascular diseases may confound the relationship between somatic symptoms of depression and reduced HRV. Therefore, this study examined whether reduced HRV was differentially associated with cognitive–affective and somatic symptoms of depression in medically healthy individuals with and without dysphoria.

Methods: Self-reported cognitive–affective and somatic symptoms as measured with the Beck Depression Inventory-II questionnaire and time and frequency domain parameters of HRV were collected in 62 medically healthy individuals, of whom 25 with and 37 without dysphoria.

Results: Somatic, but not cognitive–affective, symptoms of depression were inversely associated with SD of NN intervals (β = -0.476, p < 0.05), number of interval differences of successive NN intervals greater than 50 ms (NN50; β = -0.498, p < 0.03), and HRV total power (β = -0.494, p < 0.04) in the group with dysphoria, after controlling for sex, anxiety, and lifestyle factors. Cognitive–affective and somatic symptoms were not related to any of the HRV parameters in the group without dysphoria (all ps > 0.24).

Conclusion: By showing that the relationship between somatic depressive symptoms and reduced HRV extends to medically healthy individuals with dysphoria, the present findings suggest that this association is independent of factors concomitant with cardiovascular diseases. The present study also suggests that individuals with somatic rather than cognitive–affective subsets of depressive symptoms may be at greater risk for developing cardiovascular diseases.