No relation between fMRI findings and thought distortion in mood disorder? A claim for new studies

Adriana Munhoz Carneiro ^1,2* Pedro Henrique Rodrigues da Silva ² Valquiria Aparecida Da Silva ² Andre R Brunoni ²

• ¹ Mood Disorders Unit, Faculty of Medicine FMUSP, SAO PAULO, Brazil
• ² Other, SAO PAULO, Brazil

Depression and bipolar disorder are two of the most common disability diseases worldwide (1). Despite extensive research, treatment remains challenging; around 30-50% of the patients do not respond to initial pharmacological treatments, and only 40% achieve complete symptom remission (2). From non-pharmacological alternatives, Electroconvulsive therapy (ECT) can achieve higher response rates, however, its biological mechanisms related to this response are still unclear.By considering its complexity, a higher level of specificity is required, leading to a better treatment response and adherence, as well as lowest incidences. Considering the complexity of depression and bipolar disorders, treatment requires a higher level of specificity to achieve better treatment response and adherence, and lower their incidence. Actually, there has been a recent effort to identify functional neural substrates related to depressive symptoms. Recent efforts to identify functional neural substrates related to depressive symptoms are a promising direction to achieve this goal. Network theories of depression (3)(4)(5) suggest that depression arises from complex interactions among symptoms rather than being a distinct disorder, complicating the search for specific neural correlates of depression, but a recent study has already shown positive results of mapping symptom-specific profiles on the improvement of depressive treatment response (6).In this sense, thought distortions are considered one of the most common symptoms of depressive episodes, directly related to treatment outcomes. Directly related to treatment options, we note that thought distortions are considered one of the most common symptoms of depressive episodes. Several models have been proposed for its understanding, with the Cognitive Triad Model (7) as one of the most likely to endorse its complexity, defining distorted thoughts as depressive symptoms. According to this model, patients with depressive episodes might present thought distortions in the form of a negative view of themselves, the others, and/ or the future (8). They might manifest in the form of negative assumptions or automatic errors, causing patients to become catastrophic or ruminative; the more distortion, the more severe the symptoms.In fact, previous studies shows that patients might recover However, previous studies show that patients might recover from depressive symptoms, but still with their thought distortions, in both pharmacological (9) and non-pharmacological treatments (10), which might be interpreted in two ways: a trait, meaning a relatively enduring characteristic influenced by genetics and environment, similar to personality, or a state, considering those distortions as temporary conditions, linked to depressive episodes, that tend to decrease as patients recover from the disease (8,11). Understanding the relationship between thought contents, Magnetic Resonance Imaging (fMRI) findings, and mood disorders might be valuable for a better integrated practice. By investigating the brain function through fMRI, we can be able to investigate better approaches to understanding the mechanisms of action that are correlated with higher rates of treatment response.In this regard, we decided to perform a systematic review We decided to perform a systematic review, aiming to understand how those distortions could be related to fMRI findings how cognitive distortions can be related to fMRI findings. We considered that multimodal combinations of neuroimaging with clinical findings-collected through scales and interviews-would contribute to investigating the impact of neural networks in neuropsychiatric disorders would contribute to a better understanding of the impact of neural networks and, consequently, to a better treatment approach. For this search, we considered four electronic databases (Scopus, Embase, MEDLINE through PubMed and Web of Science) with no restriction of time or language, until may/2024. The key words were the following: for depression (depression; major depression; MDD), for bipolar disorder: bipolar, bipolar disorder, BD; for distortions: thought distortions, cognitive distortion, cognitive errors; and for neuroimage: fMRI, functional magnetic resonance imaging. No results were found from this search.The lack of studies in this area is a result of a need for more integrative solutions The lack of studies in this area shows the need for more integrative solutions for patients suffering from depression and bipolar disorder. The use of fMRI findings might contribute to identifying possible predictors of response and possible mechanisms of action in patients undergoing neurostimulation techniques (12). In the same sense, by identifying identifying this specific cluster of patients with thought distortions typically related to depressive episodes, i.e. "the higher ruminative" or "the higher catastrophizing" might also contribute to better -and personalized-more effective and more personalized pharmacological and psychosocial treatments. By neglecting the impact of one of the most studied depressive symptoms, we might be missing important information about how those thoughts are modulated and the main impact of a more precise therapy.Finally, we might conclude that understanding the interplay between brain networks and thought distortions has the potential to improve therapeutic interventions and outcomes for individuals with depression. Future research addressing these unanswered questions can pave the way for more targeted and effective treatment approaches. We recommend that future studies incorporate comprehensive data collection, focusing on disease duration, medication use, frequency of episodes, and the use of standardized measures to assess thinking distortions. These insights will strengthen the methodological rigor of research and may reveal key factors that influence treatment effectiveness, as well as the development of more individualized and personalized treatment approaches. Opinion article None. There is no need for permission to reuse or copyright. None 2 The authors declare that this manuscript was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.