Spectrum Of Depressive Symptoms Research Articles

Resting-state EEG features modulated by depressive state in healthy individuals: insights from theta PSD, theta-beta ratio, frontal-parietal PLV, and sLORETA.

Depressive states in both healthy individuals and those with major depressive disorder exhibit differences primarily in symptom severity rather than symptom type, suggesting that there is a spectrum of depressive symptoms. The increasing prevalence of mild depression carries lifelong implications, emphasizing its clinical and social significance, which parallels that of moderate depression. Early intervention and psychotherapy have shown effective outcomes in subthreshold depression. Electroencephalography serves as a non-invasive, powerful tool in depression research, with many studies employing it to discover biomarkers and explore underlying mechanisms for the identification and diagnosis of depression. However, the efficacy of these biomarkers in distinguishing various depressive states in healthy individuals and in understanding the associated mechanisms remains uncertain. In our study, we examined the power spectrum density and the region-based phase-locking value in healthy individuals with various depressive states during their resting state. We found significant differences in neural activity, even among healthy individuals. Participants were categorized into high, middle, and low depressive state groups based on their response to a questionnaire, and eyes-open resting-state electroencephalography was conducted. We observed significant differences among the different depressive state groups in theta- and beta-band power, as well as correlations in the theta-beta ratio in the frontal lobe and phase-locking connections in the frontal, parietal, and temporal lobes. Standardized low-resolution electromagnetic tomography analysis for source localization comparing the differences in resting-state networks among the three depressive state groups showed significant differences in the frontal and temporal lobes. We anticipate that our study will contribute to the development of effective biomarkers for the early detection and prevention of depression.

Unveiling the interoception impairment in various major depressive disorder stages.

The intricate pathophysiological mechanisms of major depressive disorder (MDD) necessitate the development of comprehensive early indicators that reflect the complex interplay of emotional, physical, and cognitive factors. Despite its potential to fulfill these criteria, interoception remains underexplored in MDD. This study aimed to evaluate the potential of interoception in transforming MDD's clinical practices by examining interoception deficits across various MDD stages and analyzing their complex associations with the spectrum of depressive symptoms. This study included 431 healthy individuals, 206 subclinical depression individuals, and 483 MDD patients. Depressive symptoms and interoception function were assessed using the PHQ-9 and MAIA-2, respectively. Interoception dysfunction occurred in the preclinical phase of MDD and further impaired in the clinical stage. Antidepressant therapies showed limited efficacy in improving interoception and might damage some dimensions. Interoceptive dimensions might predict depressive symptoms, primarily enhancing negative thinking patterns. The predictive model based on interoception was built with random split verification and demonstrated good discrimination and predictive performance in identifying MDD. Early alterations in the preclinical stage, multivariate associations with depressive symptoms, and good discrimination and predictive performance highlight the importance of interoception in MDD management, pointing to a paradigm shift in diagnostic and therapeutic approaches.

Attention, interpretation, and memory biases in subclinical depression: A proof-of-principle test of the combined cognitive biases hypothesis.

Emotional biases in attention, interpretation, and memory are viewed as important cognitive processes underlying symptoms of depression. To date, there is a limited understanding of the interplay among these processing biases. This study tested the dependence of memory on depression-related biases in attention and interpretation. Subclinically depressed and nondepressed participants completed a computerized version of the scrambled sentences test (measuring interpretation bias) while their eye movements were recorded (measuring attention bias). This task was followed by an incidental free recall test of previously constructed interpretations (measuring memory bias). Path analysis revealed a good fit for the model in which selective orienting of attention was associated with interpretation bias, which in turn was associated with a congruent bias in memory. Also, a good fit was observed for a path model in which biases in the maintenance of attention and interpretation were associated with memory bias. Both path models attained a superior fit compared with path models without the theorized functional relations among processing biases. These findings enhance understanding of how mechanisms of attention and interpretation regulate what is remembered. As such, they offer support for the combined cognitive biases hypothesis or the notion that emotionally biased cognitive processes are not isolated mechanisms but instead influence each other. Implications for theoretical models and emotion regulation across the spectrum of depressive symptoms are discussed.

Agomelatine: relief ensured at each and every stage of depression

In the recent years the aim of drug therapy in depression was redefined and specified. According to this, the main goal of antidepressant treatment goes beyond achieving some degree of response, or full response in the sense of 50% reduction of a depression score, but to remission in the global sense as well as on a more differentiated level, which means almost complete relief of depressive symptoms or at least almost complete relief of the core or most relevant symptoms of depression. This redefinition of the major therapeutic goal of antidepressive treatment was necessary, because several long-term studies demonstrated, that only remission and in this context the relief of the core or most relevant symptoms of depression can guarantee with a reasonably high probability a positive outcome under long-term aspects. The presentation will focus especially on the issue of relief of the core or the most relevant symptoms of depression and the respective efficacy of drug treatment with the recently licensed antidepressant agomelatine. Traditionally, especially depressed mood and lack of interest were seen as the core symptoms of depression. This is also mirrored in the current diagnostic manuals. However, considering the frequency and clinical relevance of sleep disturbances, and interpreting this in the context of the aetiopathogenetic hypothesis of disturbed circadian rhythm, sleep disorders can be interpreted as a core symptom in another sense. The same might be true for anxious symptoms, given the high neurogenetic association of depressive and anxious symptoms. Agomelatine has demonstrated powerful antidepressive efficacy, amongst others in terms of improvement of depressive mood and in terms of remission. According to its neurobiological mood of action, agomelatine has a special efficacy focus on disturbances of circadian rhythms and demonstrates clinical efficacy in this respect. Given the high frequency of anxious symptoms in depression and the comorbidity between depression and anxiety disorder, the efficacy of agomelatine in anxious symptoms also seems to be a beneficial aspect of the efficacy profile. Taken together, these findings show that agomelatine qualifies as an efficient option in the treatment of depression based on its broad efficacy on the full spectrum of depressive symptoms, including those occurring early as well as those that tend to persist late over the course of the disorder.

Cognitive Behavioural Therapy for Mood Disorders

AbstractThis paper provides a selected review of recent studies highlighting key aspects of mood disorders research. Cognitive models and clinical trials of cognitive therapy of depression are evolving and adapting to increase applicability to the spectrum of depressive symptoms and syndromes experienced by clients, as well exploring beyond acute phase treatment to relapse prevention. In contrast, cognitive models of bipolar disorders and the effectiveness of the therapy are unclear and there are more questions than answers for researchers in this area.