Cognitive control network anatomy correlates with neurocognitive behavior: A longitudinal study

Inter-identity amnesia in dissociative identity disorder resolved: A behavioural and neurobiological study

INTRODUCTION

Dissociative identity disorder (DID) is characterised by, among others, subjectively reported inter-identity amnesia, reflecting compromised information transfer between dissociative identity states. Studies have found conflicting results regarding memory transfer between dissociative identity states. Here, we investigated inter-identity amnesia in individuals with DID using self-relevant, subject specific stimuli, and behavioural and neural measures.

METHODS

Data of 46 matched participants were included; 14 individuals with DID in a trauma-avoidant state, 16 trauma-avoiding DID simulators, and 16 healthy controls. Reaction times and neural activation patterns related to three types of subject specific words were acquired and statistically analysed, namely non-self-relevant trauma-related words (NSt), self-relevant trauma-related words from a trauma-avoidant identity state (St), and trauma-related words from a trauma-related identity state (XSt).

RESULTS

We found no differences in reaction times between XSt and St words and faster reaction times for XSt over NSt. Reaction times of the diagnosed DID group were the longest. Increased brain activation to XSt words was found in the frontal and parietal regions, while decreased brain activity was found in the anterior cingulate cortex in the diagnosed DID group.

DISCUSSION

The current study reproduces and amalgamates previous behavioural reports as well as brain activation patterns. Our finding of increased cognitive control over self-relevant trauma-related knowledge processing has important clinical implications and calls for the redefinition of "inter-identity amnesia" to "inter-identity avoidance".

Understanding the mechanisms underlying cognitive control in psychosis

BACKGROUND

Cognitive control (CC) involves a top-down mechanism to flexibly respond to complex stimuli and is impaired in schizophrenia.

METHODS

This study investigated the impact of increasing complexity of CC processing in 140 subjects with psychosis and 39 healthy adults, with assessments of behavioral performance, neural regions of interest and symptom severity.

RESULTS

The lowest level of CC (Stroop task) was impaired in all patients; the intermediate level of CC (Faces task) with explicit emotional information was most impaired in patients with first episode psychosis. Patients showed activation of distinct neural CC and reward networks, but iterative learning based on the higher-order of CC during the trust game, was most impaired in chronic schizophrenia. Subjects with first episode psychosis, and patients with lower symptom load, demonstrate flexibility of the CC network to facilitate learning, which appeared compromised in the more chronic stages of schizophrenia.

CONCLUSION

These data suggest optimal windows for opportunities to introduce therapeutic interventions to improve CC.

Use of transcranial magnetic stimulation (TMS) for studying cognitive control in depressed patients: A systematic review

Major depressive disorder (MDD) is a debilitating mental disorder and the leading cause of disease burden. Major depressive disorder is associated with emotional impairment and cognitive deficit. Cognitive control, which is the ability to use perceptions, knowledge, and information about goals and motivations to shape the selection of goal-directed actions or thoughts, is a primary function of the prefrontal cortex (PFC). Psychotropic medications are one of the main treatments for MDD, but they are not effective for all patients. An alternative treatment is transcranial magnetic stimulation (TMS). Previous studies have provided mixed results on the cognitive-enhancing effects of TMS treatment in patients with MDD. Some studies have found significant improvement, while others have not. There is a lack of understanding of the specific effects of different TMS protocols and stimulation parameters on cognitive control in MDD. Thus, this review aims to synthesize the effectiveness of the TMS methods and a qualitative assessment of their potential benefits in improving cognitive functioning in patients with MDD. We reviewed 21 studies in which participants underwent a treatment of any transcranial magnetic stimulation protocol, such as repetitive TMS or theta-burst stimulation. One of the primary outcome measures was any change in the cognitive control process. Overall, the findings indicate that transcranial magnetic stimulation (TMS) may enhance cognitive function in patients with MDD. Most of the reviewed studies supported the notion of cognitive improvement following TMS treatment. Notably, improvements were predominantly observed in inhibition, attention, set shifting/flexibility, and memory domains. However, fewer significant improvements were detected in evaluations of visuospatial function and recognition, executive function, phonemic fluency, and speed of information processing. This review found evidence supporting the use of TMS as a treatment for cognitive deficits in patients with MDD. The results are promising, but further research is needed to clarify the specific TMS protocol and stimulation locations that are most effective.

Processing of auditory novelty in human cortex during a semantic categorization task

Auditory semantic novelty - a new meaningful sound in the context of a predictable acoustical environment - can probe neural circuits involved in language processing. Aberrant novelty detection is a feature of many neuropsychiatric disorders. This large-scale human intracranial electrophysiology study examined the spatial distribution of gamma and alpha power and auditory evoked potentials (AEP) associated with responses to unexpected words during performance of semantic categorization tasks. Participants were neurosurgical patients undergoing monitoring for medically intractable epilepsy. Each task included repeatedly presented monosyllabic words from different talkers ("common") and ten words presented only once ("novel"). Targets were words belonging to a specific semantic category. Novelty effects were defined as differences between neural responses to novel and common words. Novelty increased task difficulty and was associated with augmented gamma, suppressed alpha power, and AEP differences broadly distributed across the cortex. Gamma novelty effect had the highest prevalence in planum temporale, posterior superior temporal gyrus (STG) and pars triangularis of the inferior frontal gyrus; alpha in anterolateral Heschl's gyrus (HG), anterior STG and middle anterior cingulate cortex; AEP in posteromedial HG, lower bank of the superior temporal sulcus, and planum polare. Gamma novelty effect had a higher prevalence in dorsal than ventral auditory-related areas. Novelty effects were more pronounced in the left hemisphere. Better novel target detection was associated with reduced gamma novelty effect within auditory cortex and enhanced gamma effect within prefrontal and sensorimotor cortex. Alpha and AEP novelty effects were generally more prevalent in better performing participants. Multiple areas, including auditory cortex on the superior temporal plane, featured AEP novelty effect within the time frame of P3a and N400 scalp-recorded novelty-related potentials. This work provides a detailed account of auditory novelty in a paradigm that directly examined brain regions associated with semantic processing. Future studies may aid in the development of objective measures to assess the integrity of semantic novelty processing in clinical populations.

Relationship between brain structural network integrity and emotional symptoms in youth with perinatally-acquired HIV

Perinatally acquired HIV infection (PHIV) currently affects approximately 1.7 million children worldwide. Youth with PHIV (YPHIV) are at increased risk for emotional and behavioral symptoms, yet few studies have examined relationships between these symptoms and brain structure. Previous neuroimaging studies in YPHIV report alterations within the salience network (SN), cognitive control network (CCN), and default mode network (DMN). These areas have been associated with social and emotional processing, emotion regulation, and executive function. We examined structural brain network integrity from MRI using morphometric similarity networks and graph theoretical measures of segregation (transitivity), resilience (assortativity), and integration (global efficiency). We examined brain network integrity of 40 YPHIV compared to 214 youths without HIV exposure or infection. Amongst YPHIV, we related structural brain network metrics to the Emotional Symptoms Index of the Behavioral Assessment System for Children, 2nd edition. We also examined the relationship of inflammatory biomarkers in YPHIV to brain network integrity. YPHIV had significantly lower global efficiency in the SN, DMN, and the whole brain network compared to controls. YPHIV also demonstrated lower assortativity or resilience (i.e., network robustness) compared to controls in the DMN and whole brain network. Further, higher emotional symptom score was associated with higher global efficiency in the SN and lower global efficiency in the DMN, signaling more emotional challenges. A significant association was also found between several inflammatory and cardiac markers with structural network integrity. These findings suggest an impact of HIV on developing brain networks, and potential dysfunction of the SN and DMN in relation to network efficiency.

Efficacy and moderators of metacognitive training for depression in older adults (MCT-Silver): A randomized controlled trial

BACKGROUND

Up to 79 % of older adults with depression do not receive treatments commensurate with guideline recommendations. Metacognitive Training-Silver (MCT-Silver) is a low-intensity group training, which aims to reduce depressive symptoms by targeting (meta)cognitive beliefs.

METHODS

A randomized controlled trial comparing MCT-Silver (n = 41) to cognitive remediation (n = 39) was conducted with older adults with major depressive disorder and/or dysthymia. Clinician-rated depression (Hamilton Depression Rating Scale [HDRS, primary outcome]), self-reported depression (Beck Depression Inventory-II [BDI-II]), negative cognitive beliefs, positive metacognitive beliefs, rumination, health status, quality of life, and neurocognitive functioning were assessed at baseline, eight weeks (post) and three months (follow-up).

RESULTS

Both groups demonstrated moderate to large reductions in depression. No superior effects of MCT-Silver on clinician-rated depression (HDRS) were detected. MCT-Silver led to greater reductions in self-reported depression and rumination at post- and follow-up. Despite this, scores at post- and follow-up assessments were similar for both groups. MCT-Silver's effect on depressive symptoms was moderated by baseline rumination, positive metacognitive beliefs and previous treatment experience. MCT-Silver was evaluated as superior according to patient appraisals.

LIMITATIONS

Conclusions are limited by divergent findings on measures of depression and that the study was conducted during the COVID-19 pandemic.

CONCLUSIONS

Whereas no superior effect of MCT-Silver was found for the primary outcome, there was a significant effect of MCT-Silver for self-reported depression and rumination. Patients endorsing rumination and positive metacognitive beliefs as well as those without previous psychological treatment may benefit more from MCT-Silver.

Clinical-functional brain connectivity signature predicts longitudinal symptom improvement after acupuncture treatment in patients with functional dyspepsia

Whilst acupuncture has been shown to be an effective treatment for functional dyspepsia (FD), its efficacy varies significantly among patients. Knowing beforehand how each patient responds to acupuncture treatment will facilitate the ability to produce personalized prescriptions, therefore, improving acupuncture efficacy. The objective of this study was to construct the prediction model, based on the clinical-neuroimaging signature, to forecast the individual symptom improvement of FD patients following a 4-week acupuncture treatment and to identify the critical predictive features that could potentially serve as biomarkers for predicting the efficacy of acupuncture for FD. Clinical-functional brain connectivity signatures were extracted from samples in the training-test set (100 FD patients) and independent validation set (60 FD patients). Based on these signatures and support vector machine algorithms, prediction models were developed in the training test set, followed by model performance evaluation and predictive features extraction. Subsequently, the external robustness of the extracted predictive features in predicting acupuncture efficacy was evaluated by the independent validation set. The developed prediction models possessed an accuracy of 88% in predicting acupuncture responders, as well as an R2 of 0.453 in forecasting symptom relief. Factors that contributed significantly to stronger responsiveness of patients to acupuncture therapy included higher resting-state functional connectivity associated with the orbitofrontal gyrus, caudate, hippocampus, and anterior insula, as well as higher baseline scores of the Symptom Index of Dyspepsia and shorter durations of the condition. Furthermore, the robustness of these features in predicting the efficacy of acupuncture for FD was verified through various machine learning algorithms and independent samples and remained stable in univariate and multivariate analyses. These findings suggest that it is both feasible and reliable to predict the efficacy of acupuncture for FD based on the pre-treatment clinical-neuroimaging signature. The established prediction framework will promote the identification of suitable candidates for acupuncture treatment, thereby improving the efficacy and reducing the cost of acupuncture for FD.

Mild cognitive impairment in multiple system atrophy: a brain network disorder

Cognitive impairment (CI), previously considered as a non-supporting feature of multiple system atrophy (MSA), according to the second consensus criteria, is not uncommon in this neurodegenerative disorder that is clinically characterized by a variable combination of autonomic failure, levodopa-unresponsive parkinsonism, motor and cerebellar signs. Mild cognitive impairment (MCI), a risk factor for dementia, has been reported in up to 44% of MSA patients, with predominant impairment of executive functions/attention, visuospatial and verbal deficits, and a variety of non-cognitive and neuropsychiatric symptoms. Despite changing concept of CI in this synucleinopathy, the underlying pathophysiological mechanisms remain controversial. Recent neuroimaging studies revealed volume reduction in the left temporal gyrus, and in the dopaminergic nucleus accumbens, while other morphometric studies did not find any gray matter atrophy, in particular in the frontal cortex. Functional analyses detected decreased functional connectivity in the left parietal lobe, bilateral cuneus, left precuneus, limbic structures, and cerebello-cerebral circuit, suggesting that structural and functional changes in the subcortical limbic structures and disrupted cerebello-cerebral networks may be associated with early cognitive decline in MSA. Whereas moderate to severe CI in MSA in addition to prefrontal-striatal degeneration is frequently associated with cortical Alzheimer and Lewy co-pathologies, neuropathological studies of the MCI stage of MSA are unfortunately not available. In view of the limited structural and functional findings in MSA cases with MCI, further neuroimaging and neuropathological studies are warranted in order to better elucidate its pathophysiological mechanisms and to develop validated biomarkers as basis for early diagnosis and future adequate treatment modalities in order to prevent progression of this debilitating disorder.

Neuropsychological function in psychosis of epilepsy

OBJECTIVE

The neuropsychological profile of patients with psychosis of epilepsy (POE) has received limited research attention. Recent neuroimaging work in POE has identified structural network pathology in the default mode network and the cognitive control network. This study examined the neuropsychological profile of POE focusing on cognitive domains subserved by these networks.

METHODS

Twelve consecutive patients with a diagnosis of POE were prospectively recruited from the Comprehensive Epilepsy Programmes at The Royal Melbourne, Austin and St Vincent's Hospitals, Melbourne, Australia between January 2015 and February 2017. They were compared to 12 matched patients with epilepsy but no psychosis and 42 healthy controls on standardised neuropsychological tests of memory and executive functioning in a case-control design.

RESULTS

Mean scores across all cognitive tasks showed a graded pattern of impairment, with the POE group showing the poorest performance, followed by the epilepsy without psychosis and the healthy control groups. This was associated with significant group-level differences on measures of working memory (p = < 0.01); immediate (p = < 0.01) and delayed verbal recall (p = < 0.01); visual memory (p < 0.001); and verbal fluency (p = 0.02). In particular, patients with POE performed significantly worse than the healthy control group on measures of both cognitive control (p = .005) and memory (p < .001), whereas the epilepsy without psychosis group showed only memory difficulties (delayed verbal recall) compared to healthy controls (p = .001).

CONCLUSION

People with POE show reduced performance in neuropsychological functions supported by the default mode and cognitive control networks, when compared to both healthy participants and people with epilepsy without psychosis.

Disrupted Dynamic Functional Network Connectivity Among Cognitive Control Networks in the Progression of Alzheimer's Disease

Background: Alzheimer's disease (AD) is the most common age-related dementia that promotes a decline in memory, thinking, and social skills. The initial stages of dementia can be associated with mild symptoms, and symptom progression to a more severe state is heterogeneous across patients. Recent work has demonstrated the potential for functional network mapping to assist in the prediction of symptomatic progression. However, this work has primarily used static functional connectivity (sFC) from resting-state functional magnetic resonance imaging. Recently, dynamic functional connectivity (dFC) has been recognized as a powerful advance in functional connectivity methodology to differentiate brain network dynamics between healthy and diseased populations. Methods: Group independent component analysis was applied to extract 17 components within the cognitive control network (CCN) from 1385 individuals across varying stages of AD symptomology. We estimated dFC among 17 components within the CCN, followed by clustering the dFCs into 3 recurring brain states, and then estimated a hidden Markov model and the occupancy rate for each subject. Then, we investigated the link between CCN dFC features and AD progression. Also, we investigated the link between sFC and AD progression and compared its results with dFC results. Results: Progression of AD symptoms was associated with increases in connectivity within the middle frontal gyrus. Also, the very mild AD (vmAD) showed less connectivity within the inferior parietal lobule (in both sFC and dFC) and between this region and the rest of CCN (in dFC analysis). Also, we found that within-middle frontal gyrus connectivity increases with AD progression in both sFC and dFC results. Finally, comparing with vmAD, we found that the normal brain spends significantly more time in a state with lower within-middle frontal gyrus connectivity and higher connectivity between the hippocampus and the rest of CCN, highlighting the importance of assessing the dynamics of brain connectivity in this disease. Conclusion: Our results suggest that AD progress not only alters the CCN connectivity strength but also changes the temporal properties in this brain network. This suggests the temporal and spatial pattern of CCN as a biomarker that differentiates different stages of AD.

An Update on Apathy in Alzheimer's Disease

Apathy is a complex multi-dimensional syndrome that affects up to 70% of individuals with Alzheimer's disease (AD). Whilst many frameworks to define apathy in AD exist, most include loss of motivation or goal-directed behaviour as the central feature. Apathy is associated with significant impact on persons living with AD and their caregivers and is also associated with accelerated cognitive decline across the AD spectrum. Neuroimaging studies have highlighted a key role of fronto-striatial circuitry including the anterior cingulate cortex (ACC), orbito-frontal cortex (OFC) and associated subcortical structures. Importantly, the presence and severity of apathy strongly correlates with AD stage and neuropathological biomarkers of amyloid and tau pathology. Following from neurochemistry studies demonstrating a central role of biogenic amine neurotransmission in apathy syndrome in AD, recent clinical trial data suggest that apathy symptoms may improve following treatment with agents such as methylphenidate-which may have an important role alongside emerging non-pharmacological treatment strategies. Here, we review the diagnostic criteria, rating scales, prevalence, and risk factors for apathy in AD. The underlying neurobiology, neuropsychology and associated neuroimaging findings are reviewed in detail. Finally, we discuss current treatment approaches and strategies aimed at targeting apathy syndrome in AD, highlighting areas for future research and clinical trials in patient cohorts.

Reduced connectivity of the cognitive control neural network at rest in young adults who had their first drink of alcohol prior to age 18

The cognitive control network (CCN) is an important network responsible for performing and modulating executive functions. In adolescents, alcohol use has been associated with weaker cognitive control, higher reward sensitivity, and later-in-life alcohol problems. Given that the CCN continues to develop into young adulthood, it is important to understand relations between early alcohol use, the CCN, and reward networks. Participants included individuals 18-23 years without alcohol use disorder. Based upon self-reported age of first alcoholic drink, participants were split into two groups: Early (onset) Drinkers (first drink < age 18, N = 52) and Late (onset) Drinkers (first drink > age 18, N = 44). All participants underwent an 8-minute resting-state fMRI scan. Seed regions of interest included the anterior dorsolateral prefrontal cortex (DLPFC), amygdala, and ventral striatum. Early Drinkers demonstrated significant reduced connectivity of CCN regions, including bilateral anterior DLPFC, compared to Late Drinkers. There were no significant differences between Early and Late Drinkers in connectivity between reward and CCN regions. These results suggest that individuals who begin drinking alcohol earlier in life may have alterations in the development of the CCN; however, longitudinal research is necessary to determine whether lower connectivity precedes or follows early alcohol use, and any other relevant factors.

Disrupted resting-state functional connectivity of frontal network in opium use disorder

Opioid use disorder (OUD) as a chronic relapsing disorder is initially driven by dysfunction of brain reward networks and associated with several psychiatric disorders. Resting-state EEG was recorded in 24 healthy participants as well as 31 patients with OUD. Healthy participants do not meet OUD criteria. After pre-processing of the raw EEG, functional connectivity in the frontal network using eLORETA and all networks using graph analysis method were calculated. Patients with OUD had higher electrical neuronal activity compared to healthy participants in higher frequency bands. The statistical analysis revealed that patients with OUD had significantly decreased phase synchronization in β1 and β2 frequency bands compared with the healthy group in the frontal network. Regarding global network topology, we found a significant decrease in the characteristic path length and an increase in global efficiency, clustering coefficient, and transitivity in patients compared with the healthy group. These changes indicated that local specialization and global integration of the brain were disrupted in OUD and it suggests a tendency toward random network configuration of functional brain networks in patients with OUD. Disturbances in EEG-based brain network indices might reflect an altered cortical functional network in OUD. These findings might provide useful biomarkers to understand cortical brain pathology in opium use disorder.

Association between mobile phone addiction, chronotype and nonsuicidal self-injury among adolescents: A large-scale study in China

BACKGROUND

Nonsuicidal self-injury (NSSI) is a serious public health and clinical problem, particularly for adolescents, and may link to problematic smartphone use (PSU) and chronotype. This study examines the independent and interaction effects of PSU and chronotype on NSSI among adolescents and identified gender differences in these associations.

METHODS

A total of 21,357 students aged 11-19 were recruited using stratified cluster sampling across five representative provinces in China and completed standard questionnaires to record details of PSU, chronotype, and NSSI.

RESULTS

A total of 38.1 % of students reported having engaged in NSSI and 17.7 % had PSU. PSU and chronotype were significantly associated with NSSI among adolescents, and this relationship was stronger in females. Interaction analysis indicated that E-type and PSU were interactively associated with increased risks of NSSI.

CONCLUSION

The findings suggest that E-type and PSU can increase the risk of NSSI both independently and interactively. Therefore, they should be considered in intervention programs for NSSI, especially for females.

The alterations of spontaneous neural activities and white matter microstructures in anti-N-methyl-D-aspartate receptor encephalitis: a resting-state fMRI and DTI study

BACKGROUND AND PURPOSE

Limited studies had jointly excavated the structural and functional changes in cognitive deficit in anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis patients. We aimed to explore these changes in anti-NMDAR patients and their effect on cognitive function.

METHODS

Twenty-three patients and 25 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging, diffusion tensor imaging scanning, and neuroethology tests. The significantly differentiated brain regions via the fractional amplitude of low-frequency fluctuation (fALFF) were defined as regions of interest (ROIs). Granger causal, functional connectivity, and tract-based spatial statistical analyses were applied to explore the functional changes in ROIs and assess the structural changes.

RESULTS

HCs outperformed patients in Montreal Cognitive Assessment. The fALFF values of right gyrus rectus (RGR) in patients were significantly reduced. The fractional anisotropy (FA) values of WM in the genu of corpus callosum and right superior corona radiata were significantly decreased and positively associated with neuroethology testing scores. The Granger causal connectivity (GCC) from the left inferior parietal lobule to RGR was significantly decreased and positively associated with inherent vigilance. Indicated by the multiple linear regression result, decreased FA value of the right superior corona radiata might be a reliable marker that reflects the cognitive impairment.

CONCLUSIONS

Significant changes in spontaneous neural activities, GCC, and WM structures in anti-NMDAR encephalitis were reported. These findings promote the understanding of underlying relationships between cerebral function, structural network alterations, and cognitive dysfunction.

Longitudinal changes in neural gain and its relationship to cognitive control trajectory in young adults with early psychosis

The mixed cognitive outcomes in early psychosis (EP) have important implications for recovery. In this longitudinal study, we asked whether baseline differences in the cognitive control system (CCS) in EP participants would revert toward a normative trajectory seen in healthy controls (HC). Thirty EP and 30 HC undertook functional MRI at baseline using the multi-source interference task-a paradigm that selectively introduces stimulus conflict-and 19 in each group repeated the task at 12 months. Activation of the left superior parietal cortex normalized over time for the EP group, relative to HC, coincident with improvements in reaction time and social-occupational functioning. To examine these group and timepoint differences, we used dynamic causal modeling to infer changes in effective connectivity between regions underlying the MSIT task execution, namely visual, anterior insula, anterior cingulate, and superior parietal cortical regions. To resolve stimulus conflict, EP participants transitioned from an indirect to a direct neuromodulation of sensory input to the anterior insula over timepoints, though not as strongly as HC participants. Stronger direct nonlinear modulation of the anterior insula by the superior parietal cortex at follow-up was associated with improved task performance. Overall, normalization of the CCS through adoption of more direct processing of complex sensory input to the anterior insula, was observed in EP after 12 months of treatment. Such processing of complex sensory input reflects a computational principle called gain control, which appears to track changes in cognitive trajectory within the EP group.

Effect of cognitive training on patients with breast cancer reporting cognitive changes: a systematic review and meta-analysis

OBJECTIVES

Cognitive training is a non-drug intervention to improve the cognitive function of participants by training them in different cognitive domains. We investigated the effectiveness of cognitive training for patients with breast cancer reporting cognitive changes.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase, Cochrane Library, WOS, CINAHL, CNKI, VIP, SinoMed, Wanfang, Grey literature and trial registries were searched (from inception to 1 October 1, 2022).

ELIGIBILITY CRITERIA

Inclusion of randomized controlled trials (RCTs) assessing the effects of cognitive training on breast cancer patients reporting cognitive changes The primary outcome was subjective cognitive function. Secondary outcomes were objective cognitive functioning (eg, executive functioning and attention) and psychological outcomes(eg, anxiety, depression, and fatigue).

DATA EXTRACTION AND SYNTHESIS

Two reviewers worked independently to screen the literature, extract data, and assess the methodological quality and risk bias of the included studies. Results are reported as standardizedstandardised mean differences (SMDs) with 95% confidence intervals(CI). Grades of Recommendation, Assessment, Development, and Evaluation(GRADE) were used to assess the quality of evidence.

MAIN OUTCOMES AND MEASURES

The primary outcome was subjective cognitive function. Secondary outcomes were objective cognitive functioning (eg, executive functioning and attention) and psychological outcomes(eg, anxiety, depression and fatigue).

RESULTS

A total of 9 RCTs involving 666 patients with breast cancer were included. The frequency of cognitive training varied and the duration was mostly focused on 5-12 weeks. It can be delivered to patients in an individual or group mode, both online and face to face. Meta-analysis revealed that cognitive training aimed at adaptive training in cognitive field has statistically significant effects on improving subjective cognitive function (SMD=0.30, 95% CI (0.08 to 0.51), moderate certainty). Some objective cognitive functions such as processing speed (SMD=0.28, 95% CI (0.02 to 0.54), low certainty), verbal memory (SMD=0.32, 95% CI (0.05 to 0.58), moderate certainty), working memory (SMD=0.39, 95% CI (0.17 to 0.61), moderate certainty) and episodic memory (SMD=0.40, 95% CI (0.11 to 0.69), moderate certainty) were significantly improved after the intervention. In addition, we did not find statistically significant changes in attention, short-term memory, execution function, depression, anxiety and fatigue in patients with breast cancer after the intervention. Subgroup analyses revealed that based on the delivery of individual sessions, the use of web-based cognitive training software may be more beneficial in improving the outcome of the intervention.

CONCLUSION

Evidence of low to moderate certainty suggests that cognitive training may improve subjective cognition, processing speed, verbal memory, working memory and episodic memory in patients with breast cancer reporting cognitive changes. But it did not improve patients' attention, short-term memory, executive function, depression, anxiety and fatigue.

PROSPERO REGISTRATION NUMBER

CRD42021264316.

Resting state functional connectivity as a marker of internalizing disorder onset in high-risk youth

While research has linked alterations in functional connectivity of the default mode (DMN), cognitive control (CCN), and salience networks (SN) to depression and anxiety, little research has examined whether these alterations may be premorbid vulnerabilities. This study examined resting state functional connectivity (RSFC) of the CCN, DMN, and SN as markers of risk for developing an onset of a depressive or anxiety disorder in adolescents at high familial risk for these disorders. At baseline, 135 participants aged 11-17 completed resting-state functional magnetic resonance imaging, measures of internalizing symptoms, and diagnostic interviews to assess history of depressive and anxiety disorders. Diagnostic assessments were completed again at 9- or 18-month follow-up for 112 participants. At baseline, increased CCN connectivity to areas of the visual network, and decreased connectivity between the left SN and the precentral gyrus, predicted an increased likelihood of a new onset at follow-up. Increased connectivity between the right SN and postcentral gyrus at baseline predicted first episode onsets at follow-up. Altered connectivity between these regions may represent a risk factor for developing a clinically significant onset of an internalizing disorder. Results may have implications for understanding the neural bases of internalizing disorders for early identification and prevention efforts.

Structural and Functional Neural Correlates in Individuals with Excessive Smartphone Use: A Systematic Review and Meta-Analysis

Background: Despite known association of internet addiction with a reduced brain volume and abnormal connectivity, the impact of excessive smartphone use remains unclear. Methods: PubMed, Embase, ClinicalTrial.gov, and Web of Science databases were systematically searched from inception to July 2022 using appropriate keywords for observational studies comparing differences in brain volumes and activations between excessive smartphone users and individuals with regular use by magnetic resonance imaging. Results: Of the 11 eligible studies retrieved from 6993 articles initially screened, seven and six evaluated brain volumes and activations, respectively. The former enrolled 421 participants (165 excessive smartphone users vs. 256 controls), while the latter recruited 276 subjects with 139 excessive smartphone users. The results demonstrated a smaller brain volume in excessive smartphone users compared to the controls (g = −0.55, p < 0.001), especially in subcortical regions (p < 0.001). Besides, the impact was more pronounced in adolescents than in adults (p < 0.001). Regression analysis revealed a significant positive association between impulsivity and volume reduction. Regarding altered activations, the convergences of foci in the declive of the posterior lobe of cerebellum, the lingual gyrus, and the middle frontal gyrus were noted. Conclusions: Our findings demonstrated a potential association of excessive smartphone use with a reduced brain volume and altered activations.

Through the looking glass: Deep interpretable dynamic directed connectivity in resting fMRI

Brain network interactions are commonly assessed via functional (network) connectivity, captured as an undirected matrix of Pearson correlation coefficients. Functional connectivity can represent static and dynamic relations, but often these are modeled using a fixed choice for the data window Alternatively, deep learning models may flexibly learn various representations from the same data based on the model architecture and the training task. However, the representations produced by deep learning models are often difficult to interpret and require additional posthoc methods, e.g., saliency maps. In this work, we integrate the strengths of deep learning and functional connectivity methods while also mitigating their weaknesses. With interpretability in mind, we present a deep learning architecture that exposes a directed graph layer that represents what the model has learned about relevant brain connectivity. A surprising benefit of this architectural interpretability is significantly improved accuracy in discriminating controls and patients with schizophrenia, autism, and dementia, as well as age and gender prediction from functional MRI data. We also resolve the window size selection problem for dynamic directed connectivity estimation as we estimate windowing functions from the data, capturing what is needed to estimate the graph at each time-point. We demonstrate efficacy of our method in comparison with multiple existing models that focus on classification accuracy, unlike our interpretability-focused architecture. Using the same data but training different models on their own discriminative tasks we are able to estimate task-specific directed connectivity matrices for each subject. Results show that the proposed approach is also more robust to confounding factors compared to standard dynamic functional connectivity models. The dynamic patterns captured by our model are naturally interpretable since they highlight the intervals in the signal that are most important for the prediction. The proposed approach reveals that differences in connectivity among sensorimotor networks relative to default-mode networks are an important indicator of dementia and gender. Dysconnectivity between networks, specially sensorimotor and visual, is linked with schizophrenic patients, however schizophrenic patients show increased intra-network default-mode connectivity compared to healthy controls. Sensorimotor connectivity was important for both dementia and schizophrenia prediction, but schizophrenia is more related to dysconnectivity between networks whereas, dementia bio-markers were mostly intra-network connectivity.

Alterations of voxel-wise spontaneous activity and corresponding brain functional networks in multiple system atrophy patients with mild cognitive impairment

Emerging evidence has indicated that cognitive impairment is an underrecognized feature of multiple system atrophy (MSA). Mild cognitive impairment (MCI) is related to a high risk of dementia. However, the mechanism underlying MCI in MSA remains controversial. In this study, we conducted the amplitude of low-frequency fluctuation (ALFF) and seed-based functional connectivity (FC) analyses to detect the characteristics of local neural activity and corresponding network alterations in MSA patients with MCI (MSA-MCI). We enrolled 80 probable MSA patients classified as cognitively normal (MSA-NC, n = 36) and MSA-MCI (n = 44) and 40 healthy controls. Compared with MSA-NC, MSA-MCI exhibited decreased ALFF in the right dorsal lateral prefrontal cortex (RDLPFC) and increased ALFF in the right cerebellar lobule IX and lobule IV-V. In the secondary FC analyses, decreased FC in the left inferior parietal lobe (IPL) was observed when we set the RDLPFC as the seed region. Decreased FC in the bilateral cuneus, left precuneus, and left IPL and increased FC in the right middle temporal gyrus were shown when we set the right cerebellar lobule IX as the seed region. Furthermore, FC of DLPFC-IPL and cerebello-cerebral circuit, as well as ALFF alterations, were significantly correlated with Montreal Cognitive Assessment scores in MSA patients. We also employed whole-brain voxel-based morphometry analysis, but no gray matter atrophy was detected between the patient subgroups. Our findings indicate that altered spontaneous activity in the DLPFC and the cerebellum and disrupted DLPFC-IPL, cerebello-cerebral networks are possible biomarkers of early cognitive decline in MSA patients.

Brain gyrification in bipolar disorder: a systematic review of neuroimaging studies

Bipolar disorder (BD) is a severe mental illness with a strong genetic component. Genetic variations have been involved in the risk of this disorder, including those mediating brain function and neurodevelopment. Early neurodevelopment and neuroprogression processes could be reflected in brain gyrification patterns and help optimize the prediction and diagnosis of such disorders that is often delayed. Previous neuroimaging studies using this measure in patients with bipolar disorder revealed controversial results. This systematic review aimed to summarize available neuroimaging investigations on gyrification in BD compared to healthy controls (HC) and/or other psychiatric groups. Fourteen studies including 733 patients with BD, 585 patients with schizophrenia (SCZ), 90 with schizoaffective disorder (SZA), and 1380 healthy subjects were identified. Overall, a heterogeneous pattern of gyrification emerged between patients with BD and HC. Interestingly, increased gyrification or no differences were also observed in patients with BD compared to those with the schizophrenia-spectrum disorders. Furthermore, relatives of patients with BD showed lower or no differences in gyrification compared to healthy subjects without a family history of affective illness. Differences in the design and in methodological approaches could have contributed to the heterogeneity of the findings. The current review supports an altered brain gyrification pattern that underlies the pathophysiology of BD spanning large anatomical and functional neural networks, associated with altered cognitive functioning, difficulties in processing and affective regulation, and clinical symptoms. Longitudinal studies are needed to test different bipolar phenotypes and pharmacological effects on gyrification.

Effects of aging on functional connectivity in a neurodegenerative risk cohort: resting state versus task measurement using near-infrared spectroscopy

Changes in functional brain organization are considered to be particularly sensitive to age-related effects and may precede structural cognitive decline. Recent research focuses on aging processes determined by resting state (RS) functional connectivity (FC), but little is known about differences in FC during RS and cognitive task conditions in elderly participants. The purpose of this study is to compare FC within and between the cognitive control (CCN) and dorsal attention network (DAN) at RS and during a cognitive task using functional near-infrared spectroscopy (fNIRS). In a matched, neurodegenerative high-risk cohort comprising early (n = 98; 50–65 y) and late (n = 98; 65–85 y) elder subjects, FC was measured at RS and during performance of the Trail Making Test (TMT) via fNIRS. Both, under RS and task conditions our results revealed a main effect for age, characterized by reduced FC for late elder subjects within the left inferior frontal gyrus. During performance of the TMT, negative correlations of age and FC were confirmed in various regions of the CCN and DAN. For the whole sample, FC of within-region connections was elevated, while FC between regions was decreased at RS. The results confirm a reorganization of functional brain connectivity with increasing age and cognitive demands.

Distinct Patterns of Automatic and Controlled Incongruent Information Processing in the Human Brain

It is a fundamental ability to discriminate incongruent information in daily activity. However, the underlying neural dynamics are still unclear. Using stereoelectroencephalography (SEEG), in this study, we investigated the fine-grained and different states of incongruent information processing in patients with refractory epilepsy who underwent intracranial electrode implantation. All patients performed a delayed match-to-sample paradigm in the sequential pairs of visual stimuli (S1 followed by S2). Participants were asked to discriminate whether the relevant feature of S2 was identical to S1 while ignoring the irrelevant feature. The spatiotemporal cortical responses evoked by different conditions were calculated and compared, respectively, in the context of brain intrinsic functional networks. In total, we obtained SEEG recordings from 241 contacts in gray matter. In the processing of irrelevant incongruent information, the activated brain areas included the superior parietal lobule, supramarginal gyrus, angular gyrus, inferior temporal gyrus, and fusiform gyrus. By comparing the relevant incongruent condition with the congruent condition, the activated brain areas included the middle frontal gyrus, superior temporal gyrus, middle temporal gyrus, posterior superior temporal sulcus, and posterior cingulate cortex. We demonstrated the dynamics of incongruent information processing with high spatiotemporal resolution and suggested that the process of automatic detection of irrelevant incongruent information requires the involvement of local regions and relatively few networks. Meanwhile, controlled discrimination of relevant incongruent information requires the participation of extensive regions and a wide range of nodes in the network. Furthermore, both the frontoparietal control network and default mode network were engaged in the incongruent information processing.

Potential Diffusion Tensor Imaging Biomarkers for Elucidating Intra-Individual Age-Related Changes in Cognitive Control and Processing Speed

Cognitive aging, especially cognitive control, and processing speed aging have been well-documented in the literature. Most of the evidence was reported based on cross-sectional data, in which inter-individual age effects were shown. However, there have been some studies pointing out the possibility of overlooking intra-individual changes in cognitive aging. To systematically examine whether age-related differences and age-related changes might yield distinctive patterns, this study directly compared cognitive control function and processing speed between different cohorts versus follow-up changes across the adult lifespan. Moreover, considering that cognitive aging has been attributed to brain disconnection in white matter (WM) integrity, this study focused on WM integrity via acquiring diffusion-weighted imaging data with an MRI instrument that are further fitted to a diffusion tensor model (i.e., DTI) to detect water diffusion directionality (i.e., fractional anisotropy, FA; mean diffusivity, MD; radial diffusivity, RD; axial diffusivity, AxD). Following data preprocessing, 114 participants remained for further analyses in which they completed the two follow-up sessions (with a range of 1-2 years) containing a series of neuropsychology instruments and computerized cognitive control tasks. The results show that many significant correlations between age and cognitive control functions originally shown on cross-sectional data no longer exist on the longitudinal data. The current longitudinal data show that MD, RD, and AxD (especially in the association fibers of anterior thalamic radiation) are more strongly correlated to follow-up aging processes, suggesting that axonal/myelin damage is a more robust phenomenon for observing intra-individual aging processes. Moreover, processing speed appears to be the most prominent cognitive function to reflect DTI-related age (cross-sectional) and aging (longitudinal) effects. Finally, converging the results from regression analyses and mediation models, MD, RD, and AxD appear to be the representative DTI measures to reveal age-related changes in processing speed. To conclude, the current results provide new insights to which indicator of WM integrity and which type of cognitive changes are most representative (i.e., potentially to be neuroimaging biomarkers) to reflect intra-individual cognitive aging processes.

Altered Cingulum Functioning in Major Depressive Disorder Patient With Suicide Attempts: A Resting-State Functional Magnetic Resonance Imaging Study

Background

Major depressive disorder (MDD) with suicide attempts (SA) poses a significant public health issue. This study aims to identify neurobiological markers for MDD with SA on resting-state brain functional magnetic resonance imaging (rs-fMRI).

Methods

Fifty-one unmedicated adult MDD participants, 27 with SA on the Beck Scale for Suicidal Ideation and 24 without SA, underwent rs-fMRI scanning. A group of 30 healthy controls (HC) matched for age, gender, and education-level with MDD were chosen. A whole brain analysis of regional homogeneity (ReHo) was performed on subjects to identify regions where brain activity was associated with SA. Multiple comparison analysis was performed for ReHo. Pearson’s correlation analysis was performed between HAMD-SA scores and ReHo. The statistical significance level was set at p < 0.05.

Results

We examined whether there were significant differences among the three groups in whole brain ReHo during resting state. Subjects with SA showed significant increase of ReHo in the right Cingulum Post in comparison with those without SA. Subjects with SA showed significant decrease of ReHo in the right Cingulate Gyrus/Precuneus in comparison with HC. The mean ReHo from the significant brain region was associated with HAMD-SA (item 3 of the HAMD) scores (r = 0.349, P = 0.012) but was not associated with HAMD-24 scores.

Conclusion

These results indicate that SA is associated with altered resting-state brain activity. The pattern of elevated activity in the cingulum functioning may be related to SA. Identifying cingulum activity associated with SA may help to elucidate its pathogenesis and etiology.

Factors in the neurodevelopment of negative urgency: Findings from a community-dwelling sample

This study investigated neuroanatomic, genetic, cognitive, sociodemographic and emotional underpinnings of the Negative Urgency subscale of the Urgency, Premeditation, Perseverance, Sensation-Seeking and Positive Urgency Impulsive Behavior Scale in a healthy developmental sample. The goal of the investigation is to contribute to the harmonisation of behavioural, brain and neurogenetic aspects of behavioural self-control. Three domains – (1) Demographic, developmental, psychiatric and cognitive ability; (2) Regional brain volumes (neurobiological); and (3) Genetic variability (single nucleotide polymorphisms) – were examined, and models with relevant predictor variables were selected. Least absolute shrinkage and selection operator and best subset regressions were used to identify sparse models predicting negative urgency scores, which revealed that variables related to emotional regulation and right cingulate volume, as well as single nucleotide polymorphisms in CADM2 and SLC6A4, were associated with negative urgency. Our results contribute to the construct and criterion validity of negative urgency and support the hypothesis that negative urgency is a result of a complex array of influences across domains whose integration furthers developmental psychopathology research.

Depressive symptoms in cognitively unimpaired older adults are associated with lower structural and functional integrity in a frontolimbic network

Subclinical depressive symptoms are associated with increased risk of Alzheimer's disease (AD), but the brain mechanisms underlying this relationship are still unclear. We aimed to provide a comprehensive overview of the brain substrates of subclinical depressive symptoms in cognitively unimpaired older adults using complementary multimodal neuroimaging data. We included cognitively unimpaired older adults from the baseline data of the primary cohort Age-Well (n = 135), and from the replication cohort ADNI (n = 252). In both cohorts, subclinical depressive symptoms were assessed using the 15-item version of the Geriatric Depression Scale; based on this scale, participants were classified as having depressive symptoms (>0) or not (0). Voxel-wise between-group comparisons were performed to highlight differences in gray matter volume, glucose metabolism and amyloid deposition; as well as white matter integrity (only available in Age-Well). Age-Well participants with subclinical depressive symptoms had lower gray matter volume in the hippocampus and lower white matter integrity in the fornix and the posterior parts of the cingulum and corpus callosum, compared to participants without symptoms. Hippocampal atrophy was recovered in ADNI, where participants with subclinical depressive symptoms also showed glucose hypometabolism in the hippocampus, amygdala, precuneus/posterior cingulate cortex, medial and dorsolateral prefrontal cortex, insula, and temporoparietal cortex. Subclinical depressive symptoms were not associated with brain amyloid deposition in either cohort. Subclinical depressive symptoms in ageing are linked with neurodegeneration biomarkers in the frontolimbic network including brain areas particularly sensitive to AD. The relationship between depressive symptoms and AD may be partly underpinned by neurodegeneration in common brain regions.

EEG-Microstates Reflect Auditory Distraction After Attentive Audiovisual Perception Recruitment of Cognitive Control Networks

Processing of sensory information is embedded into ongoing neural processes which contribute to brain states. Electroencephalographic microstates are semi-stable short-lived power distributions which have been associated with subsystem activity such as auditory, visual and attention networks. Here we explore changes in electrical brain states in response to an audiovisual perception and memorization task under conditions of auditory distraction. We discovered changes in brain microstates reflecting a weakening of states representing activity of the auditory system and strengthening of salience networks, supporting the idea that salience networks are active after audiovisual encoding and during memorization to protect memories and concentrate on upcoming behavioural response.

Neural regions associated with gain-loss frequency and average reward in older and younger adults

Research on the biological basis of reinforcement-learning has focused on how brain regions track expected value based on average reward. However, recent work suggests that humans are more attuned to reward frequency. Furthermore, older adults are less likely to use expected values to guide choice than younger adults. This raises the question of whether brain regions assumed to be sensitive to average reward, like the medial and lateral PFC, also track reward frequency, and whether there are age-based differences. Older (60-81 years) and younger (18-30 years) adults performed the Soochow Gambling task, which separates reward frequency from average reward, while undergoing fMRI. Overall, participants preferred options that provided negative net payoffs, but frequent gains. Older adults improved less over time, were more reactive to recent negative outcomes, and showed greater frequency-related activation in several regions, including DLPFC. We also found broader recruitment of prefrontal and parietal regions associated with frequency value and reward prediction errors in older adults, which may indicate compensation. The results suggest greater reliance on average reward for younger adults than older adults.

Mindfulness and Behavior Change

Initiating and maintaining behavior change is key to the prevention and treatment of most preventable chronic medical and psychiatric illnesses. The cultivation of mindfulness, involving acceptance and nonjudgment of present-moment experience, often results in transformative health behavior change. Neural systems involved in motivation and learning have an important role to play. A theoretical model of mindfulness that integrates these mechanisms with the cognitive, emotional, and self-related processes commonly described, while applying an integrated model to health behavior change, is needed. This integrative review (1) defines mindfulness and describes the mindfulness-based intervention movement, (2) synthesizes the neuroscience of mindfulness and integrates motivation and learning mechanisms within a mindful self-regulation model for understanding the complex effects of mindfulness on behavior change, and (3) synthesizes current clinical research evaluating the effects of mindfulness-based interventions targeting health behaviors relevant to psychiatric care. The review provides insight into the limitations of current research and proposes potential mechanisms to be tested in future research and targeted in clinical practice to enhance the impact of mindfulness on behavior change.

Brain-based mechanisms of late-life depression: Implications for novel interventions

Late-life depression (LLD) is a particularly debilitating illness. Older adults suffering from depression commonly experience poor outcomes in response to antidepressant treatments, medical comorbidities, and declines in daily functioning. This review aims to further our understanding of the brain network dysfunctions underlying LLD that contribute to disrupted cognitive and affective processes and corresponding clinical manifestations. We provide an overview of a network model of LLD that integrates the salience network, the default mode network (DMN) and the executive control network (ECN). We discuss the brain-based structural and functional mechanisms of LLD with an emphasis on their link to clinical subtypes that often fail to respond to available treatments. Understanding the brain networks that underlie these disrupted processes can inform the development of targeted interventions for LLD. We propose behavioral, cognitive, or computational approaches to identifying novel, personalized interventions that may more effectively target the key cognitive and affective symptoms of LLD.

Maternal pregnancy diet, postnatal home environment and executive function and behavior in 3- to 4-y-olds

BACKGROUND

Optimal maternal nutrition during pregnancy has been linked to better cognitive and behavioral development in children. However, its influence on the effects of suboptimal postnatal exposures like reduced stimulation and support in the home is not known.

OBJECTIVES

To examine the effect of maternal pregnancy diet on executive function and/or behavioral development in children raised in suboptimal home environments.

METHODS

Data were provided by 808 mother-infant dyads from the Canadian Maternal-Infant Research on Environmental Chemicals-Child Development study. Maternal pregnancy diet was self-reported using the Healthy Eating Index 2010 questionnaire. Stimulation and support in the home was assessed using the Home Observation for Measurement of the Environment (HOME) when children were 3-4 y old. Child executive function was reported by mothers at this age using the Behavior Rating Inventory of Executive Functioning-Preschool Edition, and child behavior was assessed using the Behavior Assessment System for Children-2nd Edition. We examined the interaction of maternal pregnancy diet and postnatal HOME scores on child executive function and behavior using linear regression adjusted for maternal education, postpartum depression, prepregnancy BMI, and smoking.

RESULTS

Maternal pregnancy diet was associated with an increasingly positive association with child working memory (β: 0.21; 95% CI: 0.82, 3.41; P = 0.001), planning (β: 0.17; 95% CI: 0.38, 2.84; P = 0.007), and adaptability (β: -0.13; 95% CI: -1.72, -0.08; P = 0.032) as levels of postnatal stimulation decreased.

CONCLUSIONS

The positive association of maternal pregnancy diet quality and executive function and adaptability in 3- to 4-y-olds appeared to increase with decreasing levels of postnatal stimulation and support. These results suggest that overall maternal pregnancy diet could be linked to better child neurodevelopment in families experiencing barriers to providing stimulation and support to children in their home.

Two-Year Follow-Up Study of the Relationship Between Brain Structure and Cognitive Control Function Across the Adult Lifespan

Age-related decline in cognitive control and general slowing are prominent phenomena in aging research. These declines in cognitive functions have been shown to also involve age-related decline in brain structure. However, most evidence in support of these associations is based on cross-sectional data. Therefore, the aim of this study is to contrast cross-sectional and longitudinal analyses to re-examine if the relationship between age-related brain structure and cognitive function are similar between the two approaches. One hundred and two participants completed two sessions with an average interval of 2 years. All participants were assessed by questionnaires, a series of cognitive tasks, and they all underwent neuroimaging acquisition. The main results of this study show that the majority of the conclusions regarding age effect in cognitive control function and processing speed in the literature can be replicated based on the cross-sectional data. Conversely, when we followed up individuals over an average interval of 2 years, then we found much fewer significant relationships between age-related change in gray matter structure of the cognitive control network and age-related change in cognitive control function. Furthermore, there was no "initial age" effect in the relationships between age-related changes in brain structure and cognitive function. This finding suggests that the "aging" relationship between brain structure and cognitive function over a short period of time are independent of "initial age" difference at time point 1. The result of this study warrants the importance of longitudinal research for aging studies to elucidate actual aging processes on cognitive control function.

Insights from a laboratory and naturalistic investigation on stress, rumination and frontal brain functioning in MDD: An fNIRS study

Recent research has emphasized rumination as an important maintaining factor in various mental disorders. However, operationalization and therefore induction of rumination in experimental settings poses a major challenge in terms of ecological validity. As stress seems to play a key role in everyday situations eliciting rumination, we conducted two stress paradigms while assessing behavioral and neurophysiological measures. Aiming to replicate previous findings on induced rumination by means of the Trier Social Stress Test (TSST) and comparing them to physiological (pain) stress, a clinical sample of patients with Major Depressive Disorder (MDD; n = 22) and healthy controls (HC; n = 23) was recruited. Cortical blood oxygenation was assessed during the stress paradigms using functional near-infrared spectroscopy (fNIRS). Further, we used ecological momentary assessment (EMA) of stress, rumination and mood to be able to correlate ruminative responses during induced stress and everyday rumination. Our results showed that social stress but not physiological stress induced depressive rumination in MDD but not in HC. Further, rumination reactivity in response to social stress but not to physiological stress was significantly associated with rumination reactivity in everyday life as assessed with EMA. With respect to cortical oxygenation, MDD subjects showed hypoactivity in the Cognitive Control Network during the TSST, which mediated the differences between MDD and HC in post-stress rumination. Our findings emphasize the role of negative social triggers in depressive rumination and validate the TSST as an induction method for depressive rumination. The results inform future developments in psychotherapeutic treatment for depressive rumination.

The emotional face of anorexia nervosa: The neural correlates of emotional processing

Social-emotional processing difficulties have been reported in Anorexia Nervosa (AN), yet the neural correlates remain unclear. Previous neuroimaging work is sparse and has not used functional connectivity paradigms to more fully explore the neural correlates of emotional difficulties. Fifty-seven acutely unwell AN (AAN) women, 60 weight-recovered AN (WR) women and 69 healthy control (HC) women categorised the gender of a series of emotional faces while undergoing Functional Magnetic Resonance Imaging. The mean age of the AAN group was 19.40 (2.83), WR 18.37 (3.59) and HC 19.37 (3.36). A whole brain and psychophysical interaction connectivity approach was used. Parameter estimates from significant clusters were extracted and correlated with clinical symptoms. Whilst no group level differences in whole brain activation were demonstrated, significant group level functional connectivity differences emerged. WR participants showed increased connectivity between the bilateral occipital face area and the cingulate, precentral gyri, superior, middle, medial and inferior frontal gyri compared to AAN and HC when viewing happy valenced faces. Eating disorder symptoms and parameter estimates were positively correlated. Our findings characterise the neural basis of social-emotional processing in a large sample of individuals with AN.

Structural brain network topology underpinning ADHD and response to methylphenidate treatment

Behavioural disturbances in attention deficit hyperactivity disorder (ADHD) are thought to be due to dysfunction of spatially distributed, interconnected neural systems. While there is a fast-growing literature on functional dysconnectivity in ADHD, far less is known about the structural architecture underpinning these disturbances and how it may contribute to ADHD symptomology and treatment prognosis. We applied graph theoretical analyses on diffusion MRI tractography data to produce quantitative measures of global network organisation and local efficiency of network nodes. Support vector machines (SVMs) were used for comparison of multivariate graph measures of 37 children and adolescents with ADHD relative to 26 age and gender matched typically developing children (TDC). We also explored associations between graph measures and functionally-relevant outcomes such as symptom severity and prediction of methylphenidate (MPH) treatment response. We found that multivariate patterns of reduced local efficiency, predominantly in subcortical regions (SC), were able to distinguish between ADHD and TDC groups with 76% accuracy. For treatment prognosis, higher global efficiency, higher local efficiency of the right supramarginal gyrus and multivariate patterns of increased local efficiency across multiple networks at baseline also predicted greater symptom reduction after 6 weeks of MPH treatment. Our findings demonstrate that graph measures of structural topology provide valuable diagnostic and prognostic markers of ADHD, which may aid in mechanistic understanding of this complex disorder.

Cortical Thickness Changes in Chronic Ketamine Users

Background: Previous studies have examined the effects of long-term ketamine use on gray matter volume. But it is unclear whether chronic ketamine use alters cortical thickness and whether cortical thickness changes in chronic ketamine users are associated with cognitive deficits observed in chronic ketamine users. Methods: Here, 28 chronic ketamine users and 30 healthy controls (HCs) were recruited. Cortical morphometry based on Computational Anatomy Toolbox (CAT12) was used to measure cortical thickness. Cognitive performance was measured by MATRICS Consensus Cognitive Battery (MCCB). Two-sample t-test was used to assess differences in cortical thickness and cognitive performance between the two groups. Partial correlation analysis was used for assessing correlations between cortical thickness changes and clinical characteristics, cognitive performance in chronic ketamine users. Results: Chronic ketamine users exhibited significantly reduced cortical thickness in frontal, parietal, temporal, and occipital lobes compared to HC [false discovery rate (FDR) corrected at p < 0.05]. In chronic ketamine users, the average quantity (g) of ketamine use/day was negatively correlated with cortical thickness in the left superior frontal gyrus (SFG), right caudal middle frontal gyrus (MFG), and right paracentral lobule. The frequency of ketamine use (days per week) was negatively correlated with cortical thickness in the left isthmus cingulate cortex. Duration of ketamine use (month) was negatively correlated with cortical thickness in the left precentral gyrus. The chronic ketamine users showed significantly poorer cognitive performance on the working memory (P = 0.009), visual learning (P = 0.009), speed of processing (P < 0.000), and Matrics composite (P = 0.01). There was no correlation between scores of domains of MCCB and reduced cortical thickness. Conclusion: The present study observed reduced cortical thickness in multiple brain areas, especially in the prefrontal cortex (PFC) in chronic ketamine users. Dose, frequency, and duration of ketamine use was negatively correlated with cortical thickness of some brain areas. Our results suggest that chronic ketamine use may lead to a decrease of cortical thickness. But the present study did not observe any correlation between reduced cortical thickness and decreased cognitive performance in chronic ketamine users.

Effective Connectivity for Default Mode Network Analysis of Alcoholism

Introduction: With the recent technical advances in brain imaging modalities such as magnetic resonance imaging, positron emission tomography, and functional magnetic resonance imaging (fMRI), researchers' interests have inclined over the years to study brain functions through the analysis of the variations in the statistical dependence among various brain regions. Through its wide use in studying brain connectivity, the low temporal resolution of the fMRI represented by the limited number of samples per second, in addition to its dependence on brain slow hemodynamic changes, makes it of limited capability in studying the fast underlying neural processes during information exchange between brain regions. Materials and Methods: In this article, the high temporal resolution of the electroencephalography (EEG) is utilized to estimate the effective connectivity within the default mode network (DMN). The EEG data are collected from 20 subjects with alcoholism and 25 healthy subjects (controls), and used to obtain the effective connectivity diagram of the DMN using the Partial Directed Coherence algorithm. Results: The resulting effective connectivity diagram within the DMN shows the unidirectional causal effect of each region on the other. The variations in the causal effects within the DMN between controls and alcoholics show clear correlation with the symptoms that are usually associated with alcoholism, such as cognitive and memory impairments, executive control, and attention deficiency. The correlation between the exchanged causal effects within the DMN and symptoms related to alcoholism is discussed and properly analyzed. Conclusion: The establishment of the causal differences between control and alcoholic subjects within the DMN regions provides valuable insight into the mechanism by which alcohol modulates our cognitive and executive functions and creates better possibility for effective treatment of alcohol use disorder.

Structural variation within the left globus pallidus is associated with task-switching, not stimulus updating or distractor filtering

Cognitive control is a pivotal aspect of cognition and it is impaired in many clinical populations. To date, several distinct types of cognitive control have been proposed, and prior work demonstrated the instrumental role of basal ganglia, frontal and parietal regions. However, the role of the structural variation of these regions in cognitive control functions is poorly understood. Here, we examined in 39 adults the association between regional brain volume and three major types of cognitive control: (i) stimulus updating, (ii) task-switching, and (iii) distractor filtering. The volume of the globus pallidus was positively correlated with individual variation in task-switching , and was anatomically specific to the left hemisphere. Importantly, this region did not track performance in distractor filtering or stimulus updating. We then aimed to use transcranial direct current stimulation to target the left midline subcortical structures. However, we did not find an effect on task-switching. While the null effect in the brain stimulation prevents us from drawing causal inference from the role of globus pallidus on task-switching, our structural results reveal a novel and highly specific neurostructural mechanism for task-switching and provide a further understanding of the link between cognitive control functions and the human brain.

Intrinsic functional connectivity of the default mode and cognitive control networks relate to change in behavioral performance over two years

Understanding how brain circuitry mediates cognitive control of behavior is crucial for understanding both mental health and disease. Cognitive control describes the group of behaviors that guide goal-directed action such as sustaining attention, processing information and inhibiting impulsive responses. We rely on these behaviors for daily social, occupational and emotional functioning. Two brain networks, the cognitive control network (CCN) and default mode network (DMN), are thought to cooperate in an inverse relationship to support these functions. However, we do not yet know how connectivity within and between these networks directly relates to healthy cognitive control behaviors, and whether these interactions change over time. Here, we employed a longitudinal design to investigate if change in intrinsic connectivity in these networks will correlate with change in a range of cognitive control functions. Over two years, 109 healthy individuals, aged eight to thirty-eight, were tested twice using fMRI to assess intrinsic functional connectivity of the CCN and DMN and a validated cognitive battery. We found that increased within-network connectivity through central and left DMN was associated with increased memory performance. Additionally, decreased connectivity between posterior parietal CCN and DMN nodes and decreased connectivity between left and right dorsolateral prefrontal nodes was associated with increased cognitive performance. These findings were age and gender controlled, suggesting that age-independent plastic change in intrinsic connectivity through these networks directly relate to changing behavior. This has implications for targeting intrinsic connectivity as a possible mechanism to improve cognitive function.

Testing the Mechanism of Action of Computerized Cognitive Training in Young Adults with Depression: Protocol for a Blinded, Randomized, Controlled Treatment Trial

Background:

Depression is associated with a broad range of cognitive deficits, including processing speed (PS) and executive functioning (EF). Cognitive symptoms commonly persist with the resolution of affective symptoms and increase risk of relapse and recurrence. The cognitive control network is comprised of brain areas implicated in EF and mood regulatory functions. Prior research has demonstrated the effectiveness of computerized cognitive training (CCT) focused on PS and EF in mitigating both cognitive and affective symptoms of depression.

Methods:

Ninety participants aged 18–29 with a current diagnosis of major depressive disorder or persistent depressive disorder, or a Hamilton Depression Rating Scale score ≥12, will be randomized to either PS/EF CCT, verbal CCT, or waitlist control. Participants in the active groups will complete 15 min of training 5 days/week for 8 weeks. Clinical and neuropsychological assessments will be completed at baseline, week 4, week 8, and 3-month follow-up. Structural and functional magnetic resonance imaging (fMRI) will be completed at baseline and week 8. We will compare changes in mood, cognition, daily functioning, and fMRI data. We will explore cognitive control network functioning using resting-state and task-based fMRI.

Results:

Recruitment began in October 2019; we expect to finish recruitment by April 2022 and subsequently begin data analysis.

Conclusions:

This study is innovative in that it will include both active and waitlist control conditions and will explore changes in neural activation. Identifying the neural networks associated with improvements following CCT will allow for the development of more precise and effective interventions.

Trial Registration:

ClinicalTrials.govNCT03869463; https://clinicaltrials.gov/ct2/show/NCT03869463.

Oxytocin modulates the effective connectivity between the precuneus and the dorsolateral prefrontal cortex

Our social activity is heavily influenced by the process of introspection, with emerging research suggesting a role for the Default Mode Network (DMN) in social cognition. We hypothesize that oxytocin, a neuropeptide with an important role in social behaviour, can effectively alter the connectivity of the DMN. We test this hypothesis using a randomized, double-blind, crossover, placebo-controlled trial where 15 healthy male participants received 24 IU oxytocin or placebo prior to a resting-state functional MRI scan. We used Granger Causality Analysis for the first time to probe the role of oxytocin on brain networks and found that oxytocin reverses the pattern of effective connectivity between the bilateral precuneus and the left dorsolateral prefrontal cortex (dlPFC), a key central executive network (CEN) region. Under placebo, the bilateral precuneus exerted a significant negative causal influence on the left dlPFC and the left dlPFC exerted a significant positive causal influence on the bilateral precuneus. However, under oxytocin, these patterns were reversed, i.e. positive causal influence from the bilateral precuneus to the left dlPFC and negative causal influence from the left dlPFC to the bilateral precuneus (with statistically significant effects for the right precuneus). We propose that these oxytocin-induced effects could be a mechanistic process by which it modulates social cognition. These results provide a measurable target for the physiological effects of oxytocin in the brain and offer oxytocin as a potential agent to enhance the cooperative role of the predominantly 'task-inactive' 'default mode' brain regions in both healthy and patient populations.

Investigating the neural basis of cognitive control dysfunction in mood disorders

OBJECTIVES

Dysfunction of cognitive control is a feature of both bipolar disorder (BP) and major depression (MDD) and persists through to remission. However, it is unknown whether these disorders are characterized by common or distinct disruptions of cognitive control function and its neural basis. We investigated this gap in knowledge in asymptomatic BP and MDD participants, interpreted within a framework of normative function.

METHODS

Participants underwent fMRI scans engaging cognitive control through a working memory task and completed a cognitive battery evaluating performance across multiple subdomains of cognitive control, including attention, impulsivity, processing speed, executive function, and memory. Analysis was performed in two stages: (i) cognitive control-related brain activation and deactivation were correlated with cognitive control performance in 115 healthy controls (HCs), then, (ii) significantly correlated regions from (i) were compared between 25 asymptomatic BP, 25 remitted MDD, and with 25 different HCs, matched for age and gender.

RESULTS

Impulsivity and executive function performance were significantly worse in BP compared to both MDD and HCs. Both BP and MDD had significantly poorer memory performance compared to HCs. Greater deactivation of the medial prefrontal cortex (MPFC) during the fMRI task was associated with better executive function in healthy controls. Significantly less deactivation in this region was present in both BP and MDD compared to HCs.

CONCLUSIONS

Failure to deactivate the MPFC, a key region of the default mode network, during working memory processing is a shared neural feature present in both bipolar and major depression and could be a source of common cognitive dysfunction.

Alterations in intra- and internetwork functional connectivity associated with levetiracetam treatment in temporal lobe epilepsy

OBJECTIVE

Levetiracetam (LEV) is an antiepileptic drug with a novel pharmacological mechanism. Advances in functional magnetic resonance imaging (fMRI) enable researchers to explore the cognitive effects of antiepileptic drugs on the living brain. This study aimed to explore how the functional connectivity patterns of the cognitive networks changed in association with LEV treatment.

METHODS

Patients with temporal lobe epilepsy (TLE), including both users and nonusers of LEV, were included in this study along with healthy controls. Core cognitive networks were extracted using an independent component analysis approach. Functional connectivity patterns within and between networks were investigated. The relationships between functional connectivity patterns and clinical characteristics were also examined.

RESULTS

The patterns of intranetwork connectivity in the default mode network (DMN), left executive control network (lECN), and dorsal attention network (DAN) differed among the three groups. The internetwork interactions did not show intergroup differences once corrected for multiple comparisons. No correlation between functional connectivity and clinical characteristics was found in patients with TLE.

CONCLUSIONS

Changes in intranetwork connectivity are a key effect of LEV administration.

SIGNIFICANCE

Alterations in intranetwork connectivity patterns may underlie the cognitive effects of LEV administration; this finding improves our understanding of the neural mechanisms of LEV therapy.

Resting-state functional connectivity of the anterior cingulate cortex in young adults depressed patients with and without suicidal behavior

Functional alterations in the subregions of the anterior cingulate cortex (ACC) have been observed in patients with major depressive disorder (MDD). Studies have shown that higher depressive symptoms are associated with altered functional connectivity (FC) in different ACC sub-regions. Suicide is highly prevalent in patients with MDD; however, it is unclear whether suicidal behavior is associated with the FC alterations in the subregions of the ACC in these indibiduals. Seventy-six patients with MDD (41 with and 35 without a history of suicidal behavior) underwent functional magnetic resonance imaging (fMRI) and were assessed using the Hamilton Rating Scale for Depression (HAMD), the Scale for Suicide Ideation (SSI), and the Columbia Scale for Rating of Suicide Severity. We investigated the FC between the ACC subregions and other brain regions in young MDD patients with and without a history of suicidal behavior. The FC in the subregions of the ACC-superior frontal gyrus differed significantly between the two groups. Additionally, the anterior sgACC-right caudate FC and the pgACC-left insula FC were found to be abnormal in the suicidal MDD group. Interestingly, the suicidal ideation score positively correlated with decreased FC in the pgACC-superior frontal gyrus in both groups, but it negatively correlated with increased FC in the anterior sgACC-superior frontal gyrus in the non-suicidal MDD group. Our findings indicate that altered connections of subregions in the ACC may be involved in the neurological mechanisms underlying suicide in young adults with MDD.

Stable longitudinal associations of family income with children's hippocampal volume and memory persist after controlling for polygenic scores of educational attainment

Despite common notion that the correlation of socioeconomic status with child cognitive performance may be driven by both environmentally- and genetically-mediated transactional pathways, there is a lack of longitudinal and genetically informed research that examines these postulated associations. The present study addresses whether family income predicts associative memory growth and hippocampal development in middle childhood and tests whether these associations persist when controlling for DNA-based polygenic scores of educational attainment. Participants were 142 6-to-7-year-old children, of which 127 returned when they were 8-to-9 years old. Longitudinal analyses indicated that the association of family income with children's memory performance and hippocampal volume remained stable over this age range and did not predict change. On average, children from economically disadvantaged background showed lower memory performance and had a smaller hippocampal volume. There was no evidence to suggest that differences in memory performance were mediated by differences in hippocampal volume. Further exploratory results suggested that the relationship of income with hippocampal volume and memory in middle childhood is not primarily driven by genetic variance captured by polygenic scores of educational attainment, despite the fact that polygenic scores significantly predicted family income.

A qualitative systematic review of suicide behavior using the cognitive systems domain of the research domain criteria (RDoC) framework

Neurocognitive deficits are associated with both suicide behavior (SB) and psychiatric disorders. Application of a transdiagnostic framework to identify neurocognitive commonalities of SB may clarify important risk factors of SB across psychiatric disorders. The aim of this study was to conduct a qualitative systematic literature review of SB using the Research Domain Criteria (RDoC) Cognitive Systems framework to determine if cognitive deficits exist independently of psychiatric disorders in SB. The following six constructs that encompass the Cognitive Systems domain were assessed: 1) Attention, 2) Cognitive Control, 3) Declarative Memory, 4) Language, 5) Perception, and 6) Working Memory. A total of 1386 abstracts were identified and 74 studies met the inclusion criteria for this review. The majority of studies reviewed (65%) had significant differences in cognition between individuals with and without SB. Seventy-nine percent of studies with a patient control group showed significant cognitive deficits in SB groups. Deficits in cognitive control were associated with SB and had the greatest percentage of studies with significant main findings. Use of the RDoC cognitive systems framework to evaluate SB revealed that cognitive deficits may be a transdiagnostic risk factor for SB, especially alterations in cognitive control.