Neural correlates of cognitive behavioral therapy-based interventions for bipolar disorder: A scoping review

Cognitive Behavioral Therapy (CBT) is among the gold-standard psychotherapeutic interventions for the treatment of psychiatric disorders, including bipolar disorder (BD). While the clinical response of CBT in patients with BD has been widely investigated, its neural correlates remain poorly explored. Therefore, this scoping review aimed to discuss neuroimaging studies on CBT-based interventions in bipolar populations. Particular attention has been paid to similarities and differences between studies to inform future research. The literature search was conducted on PubMed, PsycINFO, and Web of Science databases in June 2023, identifying 307 de-duplicated records. Six studies fulfilled the inclusion criteria and were reviewed. All of them analyzed functional brain activity data. Four studies showed that the clinical response to CBT was associated with changes in the functional activity and/or connectivity of prefrontal and posterior cingulate cortices, temporal parietal junction, amygdala, precuneus, and insula. In two additional studies, a peculiar pattern of baseline activations in the prefrontal cortex, hippocampus, amygdala, and insula predicted post-treatment improvements in depressive symptoms, emotion dysregulation, and psychosocial functioning, although CBT-specific effects were not shown. These results suggest, at the very preliminary level, the potential of CBT-based interventions in modulating neural activity and connectivity of patients with BD, especially in regions ascribed to emotional processing. Nonetheless, the discrepancies between studies concerning aims, design, sample characteristics, and CBT and fMRI protocols do not allow conclusions to be drawn. Further research using multimodal imaging techniques, better-characterized BD samples, and standardized CBT-based interventions is needed.

Cannabis Dependence is Associated with Reduced Hippocampal Subregion Volumes Independently of Sex: Findings from an ENIGMA Addiction Working Group Multi-Country Study

Background: Males and females who consume cannabis can experience different mental health and cognitive problems. Neuroscientific theories of addiction postulate that dependence is underscored by neuroadaptations, but do not account for the contribution of distinct sexes. Further, there is little evidence for sex differences in the neurobiology of cannabis dependence as most neuroimaging studies have been conducted in largely male samples in which cannabis dependence, as opposed to use, is often not ascertained. Methods: We examined subregional hippocampus and amygdala volumetry in a sample of 206 people recruited from the ENIGMA Addiction Working Group. They included 59 people with cannabis dependence (17 females), 49 cannabis users without cannabis dependence (20 females), and 98 controls (33 females). Results: We found no group-by-sex effect on subregional volumetry. The left hippocampal cornu ammonis subfield 1 (CA1) volumes were lower in dependent cannabis users compared with non-dependent cannabis users (p<0.001, d=0.32) and with controls (p=0.022, d=0.18). Further, the left cornu ammonis subfield 3 (CA3) and left dentate gyrus volumes were lower in dependent versus non-dependent cannabis users but not versus controls (p=0.002, d=0.37, and p=0.002, d=0.31, respectively). All models controlled for age, intelligence quotient (IQ), alcohol and tobacco use, and intracranial volume. Amygdala volumetry was not affected by group or group-by-sex, but was smaller in females than males. Conclusions: Our findings suggest that the relationship between cannabis dependence and subregional volumetry was not moderated by sex. Specifically, dependent (rather than non-dependent) cannabis use may be associated with alterations in selected hippocampus subfields high in cannabinoid type 1 (CB1) receptors and implicated in addictive behavior. As these data are cross-sectional, it is plausible that differences predate cannabis dependence onset and contribute to the initiation of cannabis dependence. Longitudinal neuroimaging work is required to examine the time-course of the onset of subregional hippocampal alterations in cannabis dependence, and their progression as cannabis dependence exacerbates or recovers over time.

A critical overview of emotion processing assessment in non-affective and affective psychoses

AIMS

Patients with affective and non-affective psychoses show impairments in both the identification and discrimination of facial affect, which can significantly reduce their quality of life. The aim of this commentary is to present the strengths and weaknesses of the available instruments for a more careful evaluation of different stages of emotion processing in clinical and experimental studies on patients with non-affective and affective psychoses.

METHODS

We reviewed the existing literature to identify different tests used to assess the ability to recognise (e.g. Ekman 60-Faces Test, Facial Emotion Identification Test and Penn Emotion Recognition Test) and to discriminate emotions (e.g. Face Emotion Discrimination Test and Emotion Differentiation Task).

RESULTS

The current literature revealed that few studies combine instruments to differentiate between different levels of emotion processing disorders. The lack of comprehensive instruments that integrate emotion recognition and discrimination assessments prevents a full understanding of patients' conditions.

CONCLUSIONS

This commentary underlines the need for a detailed evaluation of emotion processing ability in patients with non-affective and affective psychoses, to characterise the disorder at early phases from the onset of the disease and to design rehabilitation treatments.

White matter integrity in bipolar disorder investigated with diffusion tensor magnetic resonance imaging and fractal geometry

BACKGROUND

Growing evidence suggests the presence of white matter (WM) alterations in bipolar disorder (BD). In this study we aimed to investigate the state of WM structures, in terms of tissue integrity and morphological complexity, in BD patients compared to healthy controls (HC), in an attempt to better elucidate the microstructural changes associated with BD.

METHODS

We collected a dataset of 399 Diffusion Tensor Magnetic Resonance Imaging (167 BD and 232 healthy controls) images, acquired at five different sites, which was processed with Tract-Based Spatial Statistics (TBSS) and fractal analysis.

RESULTS

The TBSS analysis demonstrated significantly lower FA values in the BD group. Diffusion abnormalities were primarily located in the temporo-parietal network. The Fractal Dimension (FD) analysis did not reveal consistent significant differences in the morphological complexity of WM structures between the groups. When the FD values of patients were considered individually, it is possible to notice some localized significant deviations from the healthy population.

LIMITATIONS

DTI sequences have not been harmonized before acquisition, samples' sizes are heterogeneous.

CONCLUSIONS

This study, by applying both TBSS and FD analyses, allows to evaluate diffusion and structural alterations of WM at the same time. The evaluation of WM integrity from these two different perspectives could be useful to better understand the pathophysiological and morphological changes underpinning bipolar disorder.

Neuropsychological instruments for bipolar disorders: A systematic review on psychometric properties

BACKGROUND

Cognitive deficits are a core feature of bipolar disorder (BD) that persist during the euthymic phase and affect global functioning. However, nowadays, there is no consensus on the optimal tool to capture cognitive deficits in BD. Therefore, this review aims to examine the psychometric properties of tools commonly used to assess cognitive functioning in BD.

METHODS

Literature search was conducted on PubMed and Web of Science databases on August 1, 2022 and on April 20, 2023, yielding 1758 de-duplicated records. Thirteen studies fulfilled the inclusion criteria and were included in the review.

RESULTS

All tools examined showed acceptable-to-good psychometric properties suggesting that both brief cognitive screeners and comprehensive batteries may be appropriate for detecting or monitoring cognitive changes in BD.

LIMITATIONS

Methodological differences between the included studies precluded a direct comparison of the results. Further research is needed to investigate the psychometric properties of cognitive tools that assess also affective and social cognition.

CONCLUSIONS

The tools examined appear sensitive enough to distinguish between BD patients with versus without cognitive deficits, however, an optimal tool has not yet been identified. The applicability and clinical utility of the tools may depend on multiple factors such as available resources. That said, web-based instruments are expected to become the first-choice instrument for cognitive screening as they can be applied on a large scale and at an affordable cost. As for second-level assessment instruments, the BACA shows robust psychometric properties and tests both affective and non-affective cognition.

White matter modifications of corpus callosum in bipolar disorder: A DTI tractography review

BACKGROUND

The recent widespread use of diffusion tensor imaging (DTI) tractography allowed researchers to investigate the diffusivity modifications and neuroanatomical changes of white matter (WM) fascicles in major psychiatric disorders, including bipolar disorder (BD). In BD, corpus callosum (CC) seems to have a crucial role in explaining the pathophysiology and cognitive impairment of this psychiatric disorder. This review aims to provide an overview on the latest results emerging from studies that investigated neuroanatomical changes of CC in BD using DTI tractography.

METHODS

Bibliographic research was conducted on PubMed, Scopus and Web of Science datasets until March 2022. Ten studies fulfilled our inclusion criteria.

RESULTS

From the reviewed DTI tractography studies a significant decrease of fractional anisotropy emerged in the genu, body and splenium of CC of BD patients compared to controls. This finding is coupled with reduction of fiber density and modification in fiber tract length. Finally, an increase of radial and mean diffusivity in forceps minor and in the entire CC was also reported.

LIMITATIONS

Small sample size, heterogeneity in terms of methodological (diffusion gradient) and clinical (lifetime comorbidity, BD status, pharmacological treatments) characteristics.

CONCLUSIONS

Overall, these findings suggest the presence of structural modifications in CC in BD patients, which may in turn explain the cognitive impairments often observed in this psychiatric disorder, especially in executive processing, motor control and visual memory. Finally, structural modifications may suggest an impairment in the amount of functional information and a morphological impact within those brain regions connected by CC.

Feasibility and preliminary efficacy of brief tele-psychotherapy for COVID-19 patients and their first-degree relatives

BACKGROUND

The SARS-CoV-2 pandemic compromised the mental health of COVID-19 patients and their family members. Due to social distancing and lockdown measures, a remote, tele-psychotherapy program for former or current COVID-19 patients and their relatives was implemented.

OBJECTIVE

The primary goal of this project was to evaluate intervention feasibility. The secondary aim was to assess the impact of the intervention by means of pre-post psychological changes.

METHODS

After a phone-based eligibility screening and remote neuropsychological testing, participants completed online self-reports assessing baseline COVID-related psychopathology. Next, participants attended eight tele-psychotherapy sessions. After treatment, the online self-reports were completed again.

RESULTS

Of 104 enrolled participants, 88 completed the intervention (84.6 % completion rate). Significant pre-post improvements were observed for generalized anxiety (d = 0.38), depression (d = 0.37), insomnia (d = 0.43), post-traumatic psychopathology (d = 0.54), and general malaise (d = 0.31). Baseline cluster analysis revealed a subgroup of 41 subjects (47.6 %) with no psychopathology, and a second subgroup of 45 subject (52.3 %) with moderate severity. Thirty-three percent of the second group reached full symptom remission, while 66 % remained symptomatic after treatment.

CONCLUSIONS

Remote brief tele-psychotherapy for COVID-19 patients and their first-degree relatives is feasible and preliminary efficacious at reducing COVID-related psychopathology in a subgroup of patients. Further research is needed to investigate distinct profiles of treatment response.

Measuring white matter microstructure in 1,457 cannabis users and 1,441 controls: A systematic review of diffusion-weighted MRI studies

INTRODUCTION

Cannabis is the most widely used regulated substance by youth and adults. Cannabis use has been associated with psychosocial problems, which have been partly ascribed to neurobiological changes. Emerging evidence to date from diffusion-MRI studies shows that cannabis users compared to controls show poorer integrity of white matter fibre tracts, which structurally connect distinct brain regions to facilitate neural communication. However, the most recent evidence from diffusion-MRI studies thus far has yet to be integrated. Therefore, it is unclear if white matter differences in cannabis users are evident consistently in selected locations, in specific diffusion-MRI metrics, and whether these differences in metrics are associated with cannabis exposure levels.

METHODS

We systematically reviewed the results from diffusion-MRI imaging studies that compared white matter differences between cannabis users and controls. We also examined the associations between cannabis exposure and other behavioral variables due to changes in white matter. Our review was pre-registered in PROSPERO (ID: 258250; https://www.crd.york.ac.uk/prospero/).

RESULTS

We identified 30 diffusion-MRI studies including 1,457 cannabis users and 1,441 controls aged 16-to-45 years. All but 6 studies reported group differences in white matter integrity. The most consistent differences between cannabis users and controls were lower fractional anisotropy within the arcuate/superior longitudinal fasciculus (7 studies), and lower fractional anisotropy of the corpus callosum (6 studies) as well as higher mean diffusivity and trace (4 studies). Differences in fractional anisotropy were associated with cannabis use onset (4 studies), especially in the corpus callosum (3 studies).

DISCUSSION

The mechanisms underscoring white matter differences are unclear, and they may include effects of cannabis use onset during youth, neurotoxic effects or neuro adaptations from regular exposure to tetrahydrocannabinol (THC), which exerts its effects by binding to brain receptors, or a neurobiological vulnerability predating the onset of cannabis use. Future multimodal neuroimaging studies, including recently developed advanced diffusion-MRI metrics, can be used to track cannabis users over time and to define with precision when and which region of the brain the white matter changes commence in youth cannabis users, and whether cessation of use recovers white matter differences.

SYSTEMATIC REVIEW REGISTRATION

www.crd.york.ac.uk/prospero/, identifier: 258250.

Brain ageing and neurodegeneration in bipolar disorder

BACKGROUND

Bipolar disorder (BD) is a psychiatric condition characterized by alternating episodes of mania and depression frequently associated with cognitive impairments. BD is associated with brain alterations in fronto-temporal and limbic networks. Recent conceptualizations view BD as a neurodegenerative disorder characterized by progressive deterioration of grey and white matter (GM, WM) volumes and accelerated brain ageing. Therefore, we conducted a review gathering neuroimaging evidence about neurodegenerative processes in BD.

METHODS

A literature search was conducted on the PubMed, Scopus and Web of Science databases in September 2021. After title and abstract screening of the retrieved records, 19 studies that met our inclusion criteria were included in the review.

RESULTS

The available evidence suggests the presence of a progressive reduction of GM volumes at the whole-brain level and in the amygdala, prefrontal regions and the anterior cingulate cortex. Conversely, WM lesions and alterations seem to emerge only in the early phases of the condition masking the effects of normal ageing. Lastly, machine learning models indicate that the gap between predicted and chronological brain age differs considerably between healthy controls and BD patients, as the latter are characterized by larger gaps.

LIMITATIONS

The included studies had cross-sectional study design, small sample sizes and heterogeneous methodology, and lack of control for pharmacological treatment.

CONCLUSIONS

BD seems to be associated with generalized age-related structural GM volumes reductions and functional brain alterations thus suggesting the presence of neurodegenerative processes. Future systematic reviews and meta-analyses should be conducted to quantify the magnitude of brain ageing-related effects in BD.

Incidental findings on brain MRI in patients with first-episode and chronic psychosis

Brain incidental findings (IFs) are unexpected brain abnormalities detected by a structural magnetic resonance (MRI) examination. We conducted a study to assess whether brain IFs are associated with first-episode psychosis (FEP) and chronic psychosis (affective vs. non-affective) compared to healthy controls (HC). Chi-squared analyses were run to compare the frequency of several IFs across groups. Logistic regression analyses were run to explore the association between group and IFs, accounting for sex, age, MRI field strength. We observed a higher frequency of most IFs in both FEP and chronic psychosis groups compared to HC, however most of the chi-squared tests did not reach significance. Patients with FEP and chronic psychosis were 3-4 times more likely to show deep white matter hyperintensities (WMH) than HC. Patients with FEP and affective chronic psychosis were 3-4 times more likely to show ventricular asymmetries than HC. All chronic patients were more likely to show periventricular WMH, liquoral spaces enlargements and ventricular system enlargements respectively. Our results suggest that deep WMH and ventricular asymmetries are associated with both the early and the chronic stages of psychosis, thus representing potential vulnerability factors already present before the onset of the symptoms, possibly due to neurodevelopmental insults.

The Italian version of the Brief Assessment of Cognition in Affective Disorders: performance of patients with bipolar disorder and healthy controls

OBJECTIVES

Cognitive deficits in Bipolar Disorder (BD) are significant enough to have an impact on daily functioning. Therefore, appropriate tools must be used to improve our understanding of the nature and severity of cognitive deficits in BD. In this study, we aimed to compare the cognitive profiles of patients with BD and healthy controls (HC) applying the Italian version of the Brief Assessment of Cognition in Affective Disorders (BAC-A).

METHODS

This cross-sectional study included 127 patients with BD and 134 HC. The participants' cognitive profiles were evaluated using the Italian version of the BAC-A, which assesses verbal memory, working memory, motor speed, verbal fluency, attention & processing speed, executive functions, and two new measures of affective processing. The BAC-A raw scores were corrected using the normative data for the Italian population. In addition, we explored whether intelligence quotient (IQ) and specific clinical variables would predict the BAC-A affective, non-affective, and total composite scores of patients with BD and HC.

RESULTS

HC performed better than patients with BD in all BAC-A subtests (all p < .001), except for subtests of the Affective Interference Test. (p ≥ .05). The effect sizes varied in magnitude and ranged between d = 0.02 and d = 1.27. In patients with BD, lower BAC-A composite scores were predicted by a higher number of hospitalizations. There was a significant association between IQ and BAC-A composite scores in both bipolar patients and HC.

CONCLUSIONS

The Italian BAC-A is sensitive to the cognitive impairments of patients with BD in both affective and non-affective cognitive domains.

The Influence of 5-HTTLPR, BDNF Rs6265 and COMT Rs4680 Polymorphisms on Impulsivity in Bipolar Disorder: The Role of Gender

Impulsivity has been proposed as an endophenotype for bipolar disorder (BD); moreover, impulsivity levels have been shown to carry prognostic significance and to be quality-of-life predictors. To date, reports about the genetic determinants of impulsivity in mood disorders are limited, with no studies on BD individuals. Individuals with BD and healthy controls (HC) were recruited in the context of an observational, multisite study (GECOBIP). Subjects were genotyped for three candidate single-nucleotide polymorphisms (SNPs) (5-HTTLPR, COMT rs4680, BDNF rs6265); impulsivity was measured through the Italian version of the Barratt Impulsiveness Scale (BIS-11). A mixed-effects regression model was built, with BIS scores as dependent variables, genotypes of the three polymorphisms as fixed effects, and centers of enrollment as random effect. Compared to HC, scores for all BIS factors were higher among subjects with euthymic BD (adjusted β for Total BIS score: 5.35, p < 0.001). No significant interaction effect was evident between disease status (HC vs. BD) and SNP status for any polymorphism. Considering the whole sample, BDNF Met/Met homozygosis was associated with lower BIS scores across all three factors (adjusted β for Total BIS score: −10.2, p < 0.001). A significant 5-HTTLPR x gender interaction was found for the SS genotype, associated with higher BIS scores in females only (adjusted β for Total BIS score: 12.0, p = 0.001). Finally, COMT polymorphism status was not significantly associated with BIS scores. In conclusion, BD diagnosis did not influence the effect on impulsivity scores for any of the three SNPs considered. Only one SNP—the BDNF rs6265 Met/Met homozygosis—was independently associated with lower impulsivity scores. The 5-HTTLPR SS genotype was associated with higher impulsivity scores in females only. Further studies adopting genome-wide screening in larger samples are needed to define the genetic basis of impulsivity in BD.

Classification of Psychoses Based on Immunological Features: A Machine Learning Study in a Large Cohort of First-Episode and Chronic Patients

For several years, the role of immune system in the pathophysiology of psychosis has been well-recognized, showing differences from the onset to chronic phases. Our study aims to implement a biomarker-based classification model suitable for the clinical management of psychotic patients. A machine learning algorithm was used to classify a cohort of 362 subjects, including 160 first-episode psychosis patients (FEP), 70 patients affected by chronic psychiatric disorders (schizophrenia, bipolar disorder, and major depressive disorder) with psychosis (CRO) and 132 health controls (HC), based on mRNA transcript levels of 56 immune genes. Models distinguished between FEP, CRO, and HC and between the subgroup of drug-free FEP and HC with a mean accuracy of 80.8% and 90.4%, respectively. Interestingly, by using the feature importance method, we identified some immune gene transcripts that contribute most to the classification accuracy, possibly giving new insights on the immunopathogenesis of psychosis. Therefore, our results suggest that our classification model has a high translational potential, which may pave the way for a personalized management of psychosis.

The association of childhood trauma, lifetime stressful events and general psychopathological symptoms in euthymic bipolar patients and healthy subjects

BACKGROUND

Psychopathological symptoms during euthymia in Bipolar Disorder (BD) affect quality of life and predispose to the occurrence of new acute episodes, however only few studies investigated potential risk-factors. This study aims to explore the association between childhood trauma (CT), lifetime stressful events (SLEs) and psychopathological symptoms in BD patients during euthymia and controls (HC).

METHODS

A total of 261 participants (93 euthymic patients with BD, 168 HC) were enrolled. Generalized linear models and multiple logistic models were used to assess the association among the Symptom Check List-90-R (SCL-90-R), the Infancy Trauma Interview, the Paykel Life Events Scale.

RESULTS

The rate of participants reporting CT was higher in BD (n=47; 53%) than HC (n=43; 30%) (p=0.001). The experience of neglect was strongly related to BD (OR 6.5; p=0.003). CT was associated to higher scores on the SCL-90-R subscales (all the subscales except Phobia). No effects of the interaction between CT and diagnosis were found on SCL-90-R. Finally, there was a main effect of CT on lifetime SLEs (p<.001), that was not associated with diagnosis (p=0.833), nor with the interaction between CT and diagnosis (p=0.624).

LIMITATIONS

The cross-sectional design does not allow causal inferences; the exclusion of subjects reporting medical or psychiatric comorbidity limits generalizability.

CONCLUSIONS

CT was associated both to psychopathological symptoms during euthymia and the lifetime SLEs, thus it may represent a vulnerability factor influencing the course of BD. Overall, these data contribute to overcome the limited evidences documenting the influence of environmental factors on euthymic phase in BD.

Sex and dependence related neuroanatomical differences in regular cannabis users: findings from the ENIGMA Addiction Working Group

Males and females show different patterns of cannabis use and related psychosocial outcomes. However, the neuroanatomical substrates underlying such differences are poorly understood. The aim of this study was to map sex differences in the neurobiology (as indexed by brain volumes) of dependent and recreational cannabis use. We compared the volume of a priori regions of interest (i.e., amygdala, hippocampus, nucleus accumbens, insula, orbitofrontal cortex (OFC), anterior cingulate cortex and cerebellum) between 129 regular cannabis users (of whom 70 were recreational users and 59 cannabis dependent) and 114 controls recruited from the ENIGMA Addiction Working Group, accounting for intracranial volume, age, IQ, and alcohol and tobacco use. Dependent cannabis users, particularly females, had (marginally significant) smaller volumes of the lateral OFC and cerebellar white matter than recreational users and controls. In dependent (but not recreational) cannabis users, there was a significant association between female sex and smaller volumes of the cerebellar white matter and OFC. Volume of the OFC was also predicted by monthly standard drinks. No significant effects emerged the other brain regions of interest. Our findings warrant future multimodal studies that examine if sex and cannabis dependence are specific key drivers of neurobiological alterations in cannabis users. This, in turn, could help to identify neural pathways specifically involved in vulnerable cannabis users (e.g., females with cannabis dependence) and inform individually tailored neurobiological targets for treatment.

Gender-related neuroanatomical differences in alcohol dependence: findings from the ENIGMA Addiction Working Group

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We tested gender differences in brain volumes of alcohol dependent vs control groups.

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Group differences in brain volumes emerged as gross and widespread.

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Group-by-gender effects emerged in selected brain regions (cerebellum, amygdala)

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In dependent users, greater alcohol use predicted smaller amygdala and larger cerebellum GM volume.

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Our results highlight the need to account for gender differences in MRI studies of alcohol dependence.

Gender-related differences in the susceptibility, progression and clinical outcomes of alcohol dependence are well-known. However, the neurobiological substrates underlying such differences remain unclear. Therefore, this study aimed to investigate gender differences in the neuroanatomy (i.e. regional brain volumes) of alcohol dependence. We examined the volume of a priori regions of interest (i.e., orbitofrontal cortex, hippocampus, amygdala, nucleus accumbens, caudate, putamen, pallidum, thalamus, corpus callosum, cerebellum) and global brain measures (i.e., total grey matter (GM), total white matter (WM) and cerebrospinal fluid). Volumes were compared between 660 people with alcohol dependence (228 women) and 326 controls (99 women) recruited from the ENIGMA Addiction Working Group, accounting for intracranial volume, age and education years. Compared to controls, individuals with alcohol dependence on average had (3–9%) smaller volumes of the hippocampus (bilateral), putamen (left), pallidum (left), thalamus (right), corpus callosum, total GM and WM, and cerebellar GM (bilateral), the latter more prominently in women (right). Alcohol-dependent men showed smaller amygdala volume than control men, but this effect was unclear among women. In people with alcohol dependence, more monthly standard drinks predicted smaller amygdala and larger cerebellum GM volumes. The neuroanatomical differences associated with alcohol dependence emerged as gross and widespread, while those associated with a specific gender may be confined to selected brain regions. These findings warrant future neuroscience research to account for gender differences in alcohol dependence to further understand the neurobiological effects of alcohol dependence.

Structural neuroimaging of somatoform disorders: A systematic review

Although there has been an increment in neuroimaging research in somatoform disorders (SD), to date little is known about the neural correlates of these diseases. Therefore, in this systematic, review we aimed at summarizing the existing evidence of structural brain alterations in SD as per DSM-IV and DSM-5 criteria. Three electronic databases (Scopus, PubMed and Web of Science) were searched. Only case-control studies using structural neuroimaging were included. Forty-five out of 369 articles fulfilled inclusion criteria and were reviewed. Compared to controls, subjects with SD showed morphological alterations encompassing motor, limbic and somatosensory circuits. Although far from being conclusive, the results suggested that SD are characterized by selective alterations of large-scale brain networks implicated in cognitive control, emotion regulation and processing, stress and somatic-visceral perception. This review highlights the need for further multimodal neuroimaging studies with longitudinal designs, in larger and better-characterized samples, to elucidate the temporal and causal relationship between neuroanatomical changes and SD, which is paramount for informing tailored treatments.

Resting state networks activity in euthymic bipolar disorder

OBJECTIVES

Bipolar disorder (BD) is a psychiatric condition causing shifts in mood, energy and activity levels severely altering the quality of life of the patients even in the euthymic phase. Although widely accepted, the neurobiological bases of the disorder in the euthymic phase remain elusive. This study aims at characterizing resting state functional activity of the BD euthymic phase in order to better understand the pathogenesis of the disease and build future neurobiological models.

METHODS

Fifteen euthymic BD patients (10 females; mean age 40.2; standard deviation 13.5; range 20-61) and 27 healthy controls (HC) (21 females; mean age 37; standard deviation 10.6; range 22-60) underwent a 3T functional MRI scan at rest. Resting state activity was extracted through independent component analysis (ICA) run with automatic dimensionality estimation.

RESULTS

ICA identified 22 resting state networks (RSNs). Within-network analysis revealed decreased connectivity in the visual, temporal, motor and cerebellar RSNs of BD patients vs HC. Between-network analysis showed increased connectivity between motor area and the default mode network (DMN) partially overlapping with the fronto-parietal network (FPN) in BD patients.

CONCLUSION

Within-network analysis confirmed existing evidence of altered cerebellar, temporal, motor and visual networks in BD. Increased connectivity between the DMN and the motor area network suggests the presence of alterations of the fronto-parietal regions, precuneus and cingulate cortex in the euthymic condition. These findings indicate that specific connectivity alterations might persist even in the euthymic state suggesting the importance of examining both within and between-network connectivity to achieve a global understanding of the BD euthymic condition.

The potential role of EMDR on trauma in affective disorders: A narrative review

BACKGROUND

Eye Movement Desensitization and Reprocessing (EMDR) is a psychotherapeutic approach that has originally been developed to treat post-traumatic stress disorder (PTSD). Recently it has been suggested as a complementary therapy in a wide range of clinical conditions. In particular, affective disorders as bipolar disorder (BD) and major depressive disorder (MDD) have a higher lifetime prevalence of traumatic or stressful life events (SLEs) compared to the general population, which makes them good candidates for the application of EMDR.

METHODS

A bibliographic search on PUBMED, Scopus, and ScienceDirect of studies applying EMDR to people with a primary diagnosis of bipolar disorder (BD) and major depressive disorder (MDD) (with or without a comorbid PTSD) was conducted.

RESULTS

Literature search retrieved 15 studies, of which 3 were focused on BD and 12 on MDD. Overall, they suggest EMDR as an effective tool in reducing trauma-related but also manic and depressive symptoms, with few effect sides and high adherence rates.

LIMITATIONS

Few small studies exist with heterogeneous and not gold-standard methodology, especially for BD.

CONCLUSIONS

Overall, retrieved studies can be considered as first attempts at investigating the applicability of EMDR in affective disorders. Although far to be conclusive, preliminary evidence suggests EMDR as a useful adjunctive approach in the treatment of BD and MDD, especially when other treatments have failed. It is now the time to implement such trauma-focused therapy to larger samples of patients using more rigorous methods.

Mindfulness-based interventions in the early phase of affective and non-affective psychoses: Special Section on "Translational and Neuroscience Studies in Affective Disorders" Section Editor, Maria Nobile MD, PhD

BACKGROUND

In the last 10 years, psychological approaches based on mindfulness techniques have been proposed for the management of psychotic experiences.

METHOD

In this brief review we summarized, to our knowledge for the first time, published studies on mindfulness-based interventions (MBIs) applied to the early phase of major psychoses (affective and non-affective).

RESULTS

Despite the great variability in terms of MBIs protocols, available studies on young people at risk to develop or with a first episode of psychosis suggest MBIs as a feasible, well-tolerated and effective approach in ameliorating symptoms, functioning, emotion regulation, and finally reducing the psychological distress associated with the onset of mania and/or psychotic experience.

LIMITATIONS

The small sample size and inconsistencies between studies in terms of design, MBIs protocols and outcome measures suggest being cautious in interpreting and generalizing results. Moreover, specific guidelines are missing for the adaptation of MBIs to youth at risk of developing affective psychoses.

CONCLUSIONS

Preliminary findings show that MBIs may be considered a promising adjunctive therapy for the treatment of major psychoses in the early phases of the illness. However, the conduct of further studies in larger samples and with a more rigorous methodology is warranted to confirm the beneficial effect of MBIs in the early stages of major psychoses.

The brief assessment of cognition in affective disorders: Normative data for the Italian population

BACKGROUND

To date there are no validated tests in Italian to assess cognitive functions in Bipolar Disorder. Therefore, this study aimed to provide normative data for the Italian version of the Brief Assessment of Cognition in Affective Disorders (BAC-A), a battery targeting neuro- and affective-cognition in affective disorders.

METHODS

Data were collected from 228 healthy participants (age range: 18-67; mean age: 34.68 ± 12.15 years) across eight recruiting sites. The influence of age, sex and education was measured and adjusted for using multivariate stepwise regression models. Normative values were established by means of the Equivalent Score approach.

RESULTS

Most of the BAC-A subtests showed patterns of association with age (inversely associated with overall cognitive performance), education (positively associated with Verbal Memory and Fluency, Digit Sequencing and Affective Processing subtests) and sex (females performed better than males in the Affective Interference Test but worse in the Emotion Inhibition Task, Digit Sequencing and Tower of London).

LIMITATIONS

The sample size was not sufficiently large for developing stratified norms, using 10-years ranges. Moreover, the participants included in the study were, on average, highly educated.

CONCLUSIONS

The normative data of the BAC-A provided in this study can serve as a cognitive functioning reference for Italian-speaking participants within the age range of the study sample. This can increase the applicability of this test in both clinical and research settings. The reliability and validity of the Italian BAC-A need to be further investigated.

Temperament and character influence on depression treatment outcome

BACKGROUND

personality features have been repeatedly associated with depression treatment outcome in Major Depressive Disorder (MDD), however conclusive results are still lacking. Moreover, as for Bipolar Disorder (BD), results are only few and preliminary.

AIM

the aim of the present study was to perform an exploratory investigation of the influence of personality traits as assessed by the Temperament and Character Inventory (TCI), on principal depression treatment outcomes (non remission, non response and resistance).

METHODS

743 mood disorders patients (455 MDD (61.24%) and 288 BD (38.76%)) were recruited in the context of 6 European studies. Generalized logit models were performed to test the effects of TCI dimensions on treatment outcomes, considering possible confounders such as age, gender and education. Positive results were controlled for comorbidities (anxiety and substance use disorders) as well.

RESULTS

MDD Non-Remitters showed high Harm Avoidance (HA) and Self Transcendence (ST) (p = 0.0004, d = 0.40; p = 0.007, d = 0.36 respectively) and low Persistence (P) and Self Directedness (SD) (p = 0.05; d = 0.18; p = 0.002, d = 0.40, respectively); MDD Non-Responders showed a slightly different profile with high HA and low Reward Dependence (RD) and SD; finally, MDD Resistants showed low RD, P and Cooperativeness (C). In BD patients, only higher HA in non response was observed.

LIMITATIONS

the retrospective cross-sectional design, the TCI assessment regardless of the mood state and the small number of bipolar patients represent the main limitations.

CONCLUSION

specific TCI personality traits are associated with depression treatment outcome in MDD patients. The inclusion of such personality traits, together with other socio-demographic and clinical predictors, could ameliorate the accuracy of the prediction models available to date.

Temperament and Character Inventory in Bipolar Disorder versus Healthy Controls and Modulatory Effects of 3 Key Functional Gene Variants

BACKGROUND

Bipolar disorder (BD) has been associated with temperamental and personality traits, although the relationship is still to be fully elucidated. Several studies investigated the genetic basis of temperament and character, identifying catechol-O-methyltransferase (COMT), brain derived neurotrophic factor (BDNF), and serotonin transporter (5-HTT) gene variants as strong candidates.

METHODS

In the GECO-BIP study, 125 BD patients and 173 HC were recruited. Subjects underwent to a detailed assessment and the temperament and character inventory 125 items (TCI) was administrated. Three functional genetic variants within key candidate genes (COMT rs4680, BDNF rs6265, and the serotonin-transporter-linked polymorphic region (5-HTTLPR)) were genotyped. Univariate and multivariate analyses were performed.

RESULTS

Compared to HC, BD patients showed higher scores in novelty seeking (NS; p = 0.001), harm avoidance (HA; p < 0.001), and self transcendence (St; p < 0.001), and lower scores in self directness (p < 0.001) and cooperativeness (p < 0.001) TCI dimensions. Concerning the genetic analyses, COMT rs4680 was associated with NS in the total sample (p = 0.007) and in the male subsample (p = 0.022). When performing the analysis in the HC and BD samples, the association was confirmed only in HC (p = 0.012), and in the HC male subgroup in particular (p = 0.004). BDNF rs6265 was associated with St in the BD group (p = 0.017).

CONCLUSION

COMT rs4680 may modulate NS in males in the general population. This effect was not detected in BD patients, probably because BD alters the neurobiological basis of some TCI dimensions. BDNF rs6265 seems to modulate St TCI dimension only in BD patients, possibly modulating the previously reported association between rs6265 and BD treatment response. Further studies are needed to confirm our findings.

Similar white matter changes in schizophrenia and bipolar disorder: A tract-based spatial statistics study

Several strands of evidence reported a significant overlapping, in terms of clinical symptoms, epidemiology and treatment response, between the two major psychotic disorders—Schizophrenia (SCZ) and Bipolar Disorder (BD). Nevertheless, the shared neurobiological correlates of these two disorders are far from conclusive. This study aims toward a better understanding of possible common microstructural brain alterations in SCZ and BD. Magnetic Resonance Diffusion data of 33 patients with BD, 19 with SCZ and 35 healthy controls were acquired. Diffusion indexes were calculated, then analyzed using Tract-Based Spatial Statistics (TBSS). We tested correlations with clinical and psychological variables. In both patient groups mean diffusion (MD), volume ratio (VR) and radial diffusivity (RD) showed a significant increase, while fractional anisotropy (FA) and mode (MO) decreased compared to the healthy group. Changes in diffusion were located, for both diseases, in the fronto-temporal and callosal networks. Finally, no significant differences were identified between patient groups, and a significant correlations between length of disease and FA and VR within the corpus callosum, corona radiata and thalamic radiation were observed in bipolar disorder. To our knowledge, this is the first study applying TBSS on all the DTI indexes at the same time in both patient groups showing that they share similar impairments in microstructural connectivity, with particular regards to fronto-temporal and callosal communication, which are likely to worsen over time. Such features may represent neural common underpinnings characterizing major psychoses and confirm the central role of white matter pathology in schizophrenia and bipolar disorder.