Subregions of the fusiform gyrus are differentially involved in the attentional mechanism supporting visual mental imagery in depression.

BACKGROUND: Impaired visual mental imagery is an important symptom of depression and has gradually become an intervention target for cognitive behavioral therapy. METHODS: Our study involved a total of 25 healthy controls (HC) and 23 individuals with moderate depressive symptoms (MD). This study explored the attentional mechanism supporting visual mental imagery impairments in depression using the Vividness of Visual Imagery Questionnaire (VVIQ), attentional network test (ANT), and resting-state functional magnetic resonance imaging (rs-fMRI). The intrinsic activity of attention-related regions relative to those supporting visual mental imagery was identified in depression patients. In addition, a meta-analysis was used to describe the cognitive function related to this intrinsic activity. RESULTS: The global correlation (GCOR) of the right anterior fusiform gyrus (FG) was decreased in depression patients. Attention-related areas were concentrated in the right posterior FG; the anterior and posterior functional connectivity (FC) of the FG was decreased in depression patients. Graph theoretic analysis showed that the degree of the right anterior FG was decreased, the degree of the anterior insula was increased, and the negative connection between these two regions was strengthened in depression patients. In addition, the degree of the right anterior FG, the FC between the subregions of the right FG, and the FC between the right anterior FG and insula were correlated with VVIQ scores; however, this correlation was not significant in depression patients. The meta-analysis suggested that the changes in the anterior FG in depressed patients may stem from difficulties of semantic memory retrieval. CONCLUSION: The changed intrinsic activity of subregions of the FG relative to the semantic memory retrieval may be associated with visual mental imagery impairments in depression.

Mental Imagery in the Relationship between Alexithymia and Parental Psychological Control.

This study aims to explore the mediating role of mental imagery in the relationship between alexithymia and parental psychological control among Chinese university students. Conducted between March and April 2023, this descriptive study involved 282 volunteer participants from a university in southern China. Data collection included the Toronto Alexithymia Scale (TAS), the Parental Psychological Control Scale (PPC), and the Vividness of Visual Mental Imagery questionnaire (VVIQ). The results revealed that: (1) based on established cut-off, 81 students were identified as highly alexithymic; (2) the alexithymia group scored higher on both the TAS and PPC and lower on the VVIQ compared to the non-alexithymia and possible-alexithymia groups; and (3) mediating analysis demonstrated a strong and positive correlation between parental psychological control and alexithymia for all participants, with visual mental imagery mediating this relationship. This study underscores the interconnectedness of parental psychological control, visual mental imagery, and alexithymia among college students. The theoretical and clinical implications of these findings are also discussed.

Trait rumination in post-stress growth among Chinese college students: the chain mediating effect of distress disclosure and perceived social support.

Background: Rumination has emerged as a significant factor contributing to personal growth following periods of stress or trauma. The present study aimed to investigate the relationship between trait rumination and post-stress growth (PSG) within the context of Chinese college students who encounter mild stressors in their daily lives. Moreover, we aim to evaluate the potential mediating roles played by both distress disclosure and perceived social support in this dynamic relationship. Method: All participants completed assessments using the Adolescent Self-Rating Life Events Checklist, Rumination Response Scale, Post-Stress Growth Inventory, Distress Disclosure Index, and Perceived Social Support Scale. Correlation and mediation analyses were conducted using SPSS PROCESS 4 MACRO. Results: All students reported experiencing mild psychological impacts as a result of negative life events in the past year and displayed moderate levels of PSG. There was no significant correlation observed between the effects of negative life events and PSG. Significant negative correlations were found between trait rumination and distress disclosure, perceived social support, and PSG. Distress disclosure and perceived social support jointly operated as sequential mediators in the relationship between trait rumination and PSG among all the participants. Qualitative analyses revealed different correlation patterns of high- versus low-ruminator. Conclusion: Trait rumination affects PSG both directly and indirectly, through its influence on distress disclosure and perceived social support. Our results emphasize the significance of actively participating in distress disclosure and nurturing a robust sense of social support to counteract the detrimental effects of rumination on post-stress growth among Chinese college students.

Screening and identification of genes involved in ß-alanine biosynthesis in Bacillus subtilis.

ß-alanine is the only naturally occurring ß-amino acid, which is widely used in medicine, food, and feed fields, and generally produced through synthetic biological methods based on engineered strains of Escherichia coli or Corynebacterium glutamicum. However, the ß-alanine biosynthesis in Bacillus subtilis, a traditional industrial model microorganism of food safety grade, has not been thoroughly explored. In this study, the native l-aspartate-α-decarboxylase was overexpressed in B. subtilis 168 to obtain an increase of 842% in ß-alanine production. A total of 16 single-gene knockout strains were constructed to block the competitive consumption pathways to identify a total of 6 genes (i.e., ptsG, fbp, ydaP, yhfS, mmgA, and pckA) involved in ß-alanine synthesis, while the multigene knockout of these 6 genes obtained an increased ß-alanine production by 40.1%. Ten single-gene suppression strains with the competitive metabolic pathways inhibited revealed that the inhibited expressions of genes glmS, accB, and accA enhanced the ß-alanine production. The introduction of heterologous phosphoenolpyruvate carboxylase increased the ß-alanine production by 81.7%, which was 17-fold higher than that of the original strain. This was the first study using multiple molecular strategies to investigate the biosynthetic pathway of ß-alanine in B. subtilis and to identify the genetic factors limiting the excessive synthesis of ß-alanine by microorganisms.

The effect of secondhand smoke exposure on self-satisfaction and perceived freedom of life choice.

Objective: The present study aims to examine whether secondhand smoke exposure (SHSE) in university students can affect three indices of self-satisfaction related to depression as indiced by appearance, weight, and freedom of life choice. Participants: We collected data from 740 nonsmoking students in the summer of 2018, of which 57.84% were exposed to secondhand smoke. Methods: Depressive symptoms, SHSE, smoking status, weight satisfaction, appearance satisfaction, and freedom of life choice were self-reported via a questionnaire. Results: The generalized linear analyses revealed that SHSE was linked to lower scores of perceived freedom of life choice but not significantly associated with weight nor appearance satisfaction. The mediation analyses indicated that perceived freedom of life choice fully mediated the association between SHSE and depressive symptoms. Conclusions: These findings shed light on the importance of SHSE and its effects on mental health in university students. Preventive strategies should therefore locally target university campuses.

A Large Sample Survey of Suicide Risk among University Students in China.

BACKGROUND: This study aimed to examine suicide ideation, suicide attempts, and suicide risk by examining a large sample of Chinese university students and identify the predictive factors, including depressive and anxiety symptoms, for suicide attempt and suicide risk. METHODS: We recruited 6,836 students (aged 18-30) based on all students enrolled in 2016 from one university using cluster sampling. They completed four questionnaires: the Beck Scale for Suicide Ideation and the Suicidal Behaviors Questionnaire-Revised were used to measure suicide risk, and students' depressive/anxiety symptoms were estimated using Patient Health Questionnaire and Generalized Anxiety Disorder Scale. RESULTS: Four major findings emerged. First, 18% of the students showed high suicide ideation, 14.5% showed suicide risk, 18.8% had suicide plans, and 1% had attempted suicide. Second, a weak sense of life's value was common among university students, as 61.4% of students considered suicide as a way to end or evade problems. Third, the results of the binary logistic regression showed that education, suicide ideation, including the wish to die, attitude toward suicide, specificity/planning of suicide, and deception or concealment of contemplated suicide were predictive factors of suicide attempt and suicide risk. The variable "deterrents to active attempt" was also a predictive factor of suicide risk. Fourth, depressive and anxiety symptoms did not significantly predict suicide attempts or suicide risk. Only 10.8% and 5.6% of the students had self-reported scores above the clinical cut-off points for depression and anxiety, respectively. CONCLUSIONS: This study highlighted the prevalence of suicide risk among Chinese university students. The high risk of suicide may not only be due to affective disorders, but also a weak sense of life's value or other reasons. Suicide ideation that significantly predicts suicide risk can be used for suicide risk assessment. Universities should provide appropriate life education and suicide prevention and intervention such as teaching instructors gate-keeper skills.

The Effect of Comorbid Attention-Deficit/Hyperactivity Disorder Symptoms on Face Memory in Children with Autism Spectrum Disorder: Insights from Transdiagnostic Profiles.

Face memory impairments are common but heterogeneous in autism spectrum disorder (ASD), which may be influenced by co-occurrence with attention-deficit/hyperactivity disorder (ADHD). Here, we aimed to investigate the phenotype change of face memory in children with ASD comorbid ADHD symptoms, and discuss the potential role of executive function (EF). Ninety-eight children were analyzed in the present study, including ASD- (ASD-only, n = 24), ADHD (n = 23), ASD+ (with ADHD symptoms, n = 23) and neurotypical controls (NTC, n = 28). All participants completed two tests: face encoding and retrieving task and Wisconsin Card Sorting Test (WCST) for measuring face memory and EF, respectively. Results revealed that: compared with the NTC group, children with ASD- exhibited lower accuracy in both face encoding and retrieving, and participants with ASD+ showed lower accuracy only in the retrieving, whereas no differences were found among participants with ADHD. Moreover, in the ASD+ group, face encoding performance was correlated with response perseverative errors (RPE) and failure to maintain sets (FMS) of WCST; significantly, there were no group differences between ASD+ and NTC in these two indices. The transdiagnostic profiles indicated that comorbid ADHD symptoms could modulate the face encoding deficiency of ASD, which may be partially compensated by EF. Shared and distinct intervention strategies to improve social cognition are recommended for children undergoing treatment for each condition.

Neuropsychological effect of working memory capacity on mental rotation under hypoxia environment.

High-altitude exposure induces the decline of spatial manipulation such as mental rotation which is limited by working memory capacity, but the underlying neuropsychological effect remains to be identified. We evaluated the mental rotation task and the contralateral delay activity (CDA) task under hypoxia environment using the event-related potential. When compared with the controls, the behavior response was slowed on two tasks in the high-altitude group. The declined mental rotation and the decreased working memory capacity were synchronously related to the amplitudes of P50 and CDA, respectively. The P50 during mental rotation was positively correlated to that of rotation-related negativity (RRN) component, so was with the CDA. Time-frequency analysis showed that the beta/alpha power in mental rotation and the theta/alpha/beta power in CDA were enhanced in the high-altitude group. The present study might suggest that the decline of working memory capacity induced poor performance of mental rotation, which may be derived from a bottom-up sensory gating deficit reflected by P50.

Spontaneous Activity in Primary Visual Cortex Relates to Visual Creativity.

Cognitive and neural processes underlying visual creativity have attracted substantial attention. The current research uses a critical time point analysis (CTPA) to examine how spontaneous activity in the primary visual area (PVA) is related to visual creativity. We acquired the functional magnetic resonance imaging (fMRI) data of 16 participants at the resting state and during performing a visual creative synthesis task. According to the CTPA, we then classified spontaneous activity in the PVA into critical time points (CTPs), which reflect the most useful and important functional meaning of the entire resting-state condition, and the remaining time points (RTPs). We constructed functional brain networks based on the brain activity at two different time points and then subsequently based on the brain activity at the task state in a separate manner. We explore the relationship between resting-state and task-fMRI (T-fMRI) functional brain networks. Our results found that: (1) the pattern of spontaneous activity in the PVA may associate with mental imagery, which plays an important role in visual creativity; (2) in comparison with the RTPs-based brain network, the CTP-network showed an increase in global efficiency and a decrease in local efficiency; (3) the regional integrated properties of the CTP-network could predict the integrated properties of the creative-network while the RTP-network could not. Thus, our findings indicated that spontaneous activity in the PVA at CTPs was associated with a visual creative task-evoked brain response. Our findings may provide an insight into how the visual cortex is related to visual creativity.

Flexible reconfiguration of functional brain networks as a potential neural mechanism of creativity.

Creativity relies on the reorganizing of multimodal information and flexible switching between different modes of thinking, suggesting an association between creativity and the reconfiguration of functional brain networks. Here, we investigated global and regional brain dynamics in high-creative (HCG, N = 22) and a low-creative (LCG, N = 20) groups during a divergent creative thinking task. We found that during the creative thinking task, the HCG demonstrated higher global network flexibility, as compared to the LCG. In addition, creative thinking in the HCG was associated with significantly higher regional flexibility in the medial superior temporal gyrus, superior parietal lobule, precuneus, nucleus accumbens, and the ventral inferior frontal gyrus. Interestingly, the LCG demonstrated decreased regional flexibility in the medial superior temporal gyrus, superior parietal lobule, and the ventral inferior frontal gyrus. We also found that the changes in global and regional flexibility in the creative compared with the control tasks were good features allowing for distinguishing between the HCG and the LCG. Taken together, these findings provide evidence that divergent creative thinking is associated with flexible reconfiguration of brain networks involved in verbal, working memory, and reward processing.

Brain Activity during Visual and Auditory Word Rhyming Tasks in Cantonese-Mandarin-English Trilinguals.

It is unclear whether the brain activity during phonological processing of second languages (L2) is similar to that of the first language (L1) in trilingual individuals, especially when the L1 is logographic, and the L2s are logographic and alphabetic, respectively. To explore this issue, this study examined brain activity during visual and auditory word rhyming tasks in Cantonese-Mandarin-English trilinguals. Thirty Chinese college students whose L1 was Cantonese and L2s were Mandarin and English were recruited. Functional magnetic resonance imaging (fMRI) was conducted while subjects performed visual and auditory word rhyming tasks in three languages (Cantonese, Mandarin, and English). The results revealed that in Cantonese-Mandarin-English trilinguals, whose L1 is logographic and the orthography of their L2 is the same as L1-i.e., Mandarin and Cantonese, which share the same set of Chinese characters-the brain regions for the phonological processing of L2 are different from those of L1; when the orthography of L2 is quite different from L1, i.e., English and Cantonese who belong to different writing systems, the brain regions for the phonological processing of L2 are similar to those of L1. A significant interaction effect was observed between language and modality in bilateral lingual gyri. Regions of interest (ROI) analysis at lingual gyri revealed greater activation of this region when using English than Cantonese and Mandarin in visual tasks.

Effects of the Co-occurrence of Anxiety and Attention-Deficit/Hyperactivity Disorder on Intrinsic Functional Network Centrality among Children with Autism Spectrum Disorder.

Children with autism spectrum disorder (ASD) present with a high co-occurrence of anxiety and attention-deficit/hyperactivity disorder (ADHD). However, it remains unclear how the co-occurrence of anxiety and ADHD in children with ASD alters whole-brain functional networks. Here, we aimed to examine anxiety- and ADHD-related brain network centrality in children with ASD separately and their relationships with ASD symptoms. Clinical anxiety and ADHD levels in children with ASD, aged 6-13 years old, were assessed. Participants were categorized into four groups: ASD only (n = 28), ASD + anxiety (n = 19), ASD + ADHD (n = 25), and ASD + both anxiety and ADHD (n = 28). Subsequently, we compared voxel-wise network degree centrality (DC) among the four groups. We found that: (a) compared with ASD only, children with ASD + anxiety showed higher DC in the left middle temporal gyrus, right lingual gyrus, and left cuneus, and lower DC in the right precuneus; (b) children with ASD + ADHD presented higher DC in the right calcarine and left superior frontal gyrus (SFG) compared with ASD only; (c) children with ASD + both displayed higher DC in the right calcarine and lower centrality in the right middle occipital gyrus compared with ASD only; and (d) across all children with ASD, there was a positive correlation between DC of the right calcarine with nonverbal behavior scores, and DC of the left SFG was negatively correlated with social scores. Our findings suggest that the right calcarine, left SFG, and default mode network nodes play important roles in the co-occurrence of anxiety and ADHD among children with ASD. Autism Res 2019, 12: 1057-1068. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: The co-occurrence of anxiety and attention-deficit/hyperactivity disorder (ADHD) has been shown to influence the brain function of children with ASD. In order to gain a better understanding of this, the present study compared degree centrality, the amount of effective brain functional connectivity that reflects the characteristics of brain networks, among four groups: ASD only, ASD + anxiety, ASD + ADHD, and ASD + both anxiety and ADHD. We found that some areas located in the language processing network and primary visual cortex were associated with the co-occurrence of ADHD, and some other areas located in the default mode network were associated with the co-occurrence of both anxiety and ADHD. These findings provide more knowledge about the neural basis underlying behavioral changes related to the co-occurrence of anxiety and ADHD in children with ASD.

Altered resting state functional connectivity of the cognitive control network in fibromyalgia and the modulation effect of mind-body intervention.

This study examines altered resting state functional connectivity (rsFC) of the cognitive control network (CCN) in fibromyalgia patients as compared to healthy controls, as well as how an effective mind-body intervention, Tai Chi, can modulate the altered rsFC of the CCN. Patients with fibromyalgia and matched healthy subjects were recruited in this study. Fibromyalgia patients were scanned 12 weeks before and after intervention. The bilateral dorsolateral prefrontal cortex (DLPFC) was used as a seed to explore the rsFC of the CCN. Data analysis was conducted with 21 patients and 20 healthy subjects. Compared to healthy subjects, fibromyalgia patients exhibited increased rsFC between the DLPFC and the bilateral rostral anterior cingulate cortex (rACC) and medial prefrontal cortex (MPFC) at baseline. The rsFC between the CCN and rACC/MPFC further increased after Tai Chi intervention, and this increase was accompanied by clinical improvements. This rsFC change was also significantly associated with corresponding changes in the Overall Impact domain of the Revised Fibromyalgia Impact Questionnaire (FIQR). Further analysis showed that the rACC/MPFC rsFC with both the PAG and hippocampus significantly decreased following Tai Chi intervention. Our study suggests that fibromyalgia is associated with altered CCN rsFC and that effective mind-body treatment may elicit clinical improvements by further increasing this altered rsFC. Elucidating this mechanism of enhancing the allostasis process will deepen our understanding of the mechanisms underlying mind-body interventions in fibromyalgia patients and facilitate the development of new pain management methods.

Gender Difference in the Association Between Executive Function and Autistic Traits in Typically Developing Children.

Autistic traits and executive function (EF) were assessed in 413 typically developing children aged 6-9 years. The children were divided into the high- autistic-trait (HAT) and low-autistic-trait (LAT) groups based on their total autistic traits. Results suggested that there were gender differences in specific autistic traits in children with LAT. There were gender-specific associations between EF and autistic traits in children with HAT: the set shifting of EF predicted difficulties in social awareness in boys; whereas all the EF components predicted difficulties in social communication and social cognition in girls. These findings may have implications for developing customized interventions that are targeted at specific autistic deficits in males and females.

Eyes Closed Elevates Brain Intrinsic Activity of Sensory Dominance Networks: A Classifier Discrimination Analysis.

Brain neocortex is usually dominated by visual input (with eyes open [EO]), whereas this visual predominance could be reduced by closing eyes. Cutting off visual input from the eyes (with eyes closed [EC]) would also benefit other sensory performance; however, the neural basis underlying the state-switching remains unclear. In this study, we investigated the brain intrinsic activity of either the EO or EC states by using the resting-state functional magnetic resonance imaging data from 22 healthy participants. The 10 resting-state networks (RSNs) of these participants were explored by the independent component analysis method. Within each RSN, various network parameters (i.e., the amplitude of low-frequency fluctuation, the voxel-wise weighted degree centrality, and the RSN-wise functional connectivity) were measured to depict the brain intrinsic activity properties underlying the EO and EC states. Taking these brain intrinsic activity properties as discriminative features in a linear classifier, we found that the EO and EC states could be effectively classified using the intrinsic properties of the sensory dominance networks and the salience network (SN). Further analysis showed that the brain intrinsic activity within the sensory dominance networks was constantly overwhelmed during the EC state relative to that in the EO state. The SN might play a key role as a switcher between state-switching. Therefore, this study indicated that the brain intrinsic activity in the sensory dominance networks would be enhanced with EC, which might improve other sensory-relative task performance.

Regional Homogeneity and Multivariate Pattern Analysis of Cervical Spondylosis Neck Pain and the Modulation Effect of Treatment.

Objects: We investigated brain functional alteration in patients with chronic cervical spondylosis neck pain (CSNP) compared to healthy controls (HCs) and the effect of intervention. Methods: 104 CSNP patients and 96 matched HCs were recruited. Patients received 4 weeks of treatment. Resting-state fMRI and Northwick Park Neck Pain Questionnaire (NPQ) were collected before and after treatment. Resting state regional homogeneity (rs-ReHo) and multivariate pattern analysis (MVPA) were applied to (1) investigate rs-ReHo differences between CSNP patients and controls and the effect of longitudinal treatment and (2) classify CSNP patients from HCs and predict clinical outcomes before treatment using MVPA. Results: We found that (1) CSNP patients showed decreased rs-ReHo in the left sensorimotor cortex and right temporo-parietal junction (rTPJ), and rs-ReHo at the rTPJ significantly increased after treatment; (2) rs-ReHo at rTPJ was associated with NPQ at baseline, and pre- and post-treatment rs-ReHo changes at rTPJ were associated with NPQ changes in CSNP patients; and (3) MVPA could discriminate CSNP patients from HCs with 72% accuracy and predict clinical outcomes with a mean absolute error of 19.6%. Conclusion: CSNP patients are associated with dysfunction of the rTPJ and sensorimotor area. Significance: rTPJ plays on important role in the pathophysiology and development of CSNP.

Executive function predicts the visuospatial working memory in autism spectrum disorder and attention-deficit/hyperactivity disorder.

Children with autism spectrum disorder (ASD) and those with attention deficit/hyperactivity disorder (ADHD) always show working memory deficits. However, research findings on the factors that affected the working memory in ASD and ADHD were inconsistent. Thus, we developed the present study to investigate the association of executive function (EF) with the visuospatial working memory (VSWM) in ASD and ADHD. Three groups of participants were examined: 21 children with ASD, 28 children with ADHD and 28 typically developing (TD) children as the controls. All participants completed two tests: the Wisconsin Card Sorting Test (WCST) and the Corsi Block Tapping Test for measuring EF and VSWM, respectively. The WCST included four domains: categories achieved (CA), perseverative errors (PE), failures to maintain set (FMS), and total errors (TE). The findings indicated that (1) the ASD group showed poorer performance in VSWM than the ADHD and TD groups; (2) for the ASD group, VSWM was positively correlated with CA, and was negatively correlated with PE and TE; (3) for the ADHD group, FMS showed a negative relationship with VSWM; and (4) TE predicted the performance of VSWM in ASD group, while FMS predicted VSWM in ADHD group. The study results suggested that VSWM was impaired in ASD but not in ADHD. Also, the EF domains were differently correlated with the VSWM performance in ASD and ADHD. Our study suggests that we should consider different intervention targets of working memory and EF contributions in improving the cognitive capacity of ASD and ADHD. Autism Res 2018, 11: 1148-1156. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: The present study compared the visuospatial working memory (VSWM) in three groups of children: autism (ASD), attention deficit/hyperactivity disorder (ADHD), and typically developed children (TD). The ASD group showed poorer VSWM than the ADHD and TD groups. The total error of executive function predicted the performance of VSWM in ASD, while failures to maintain set predicted VSWM in ADHD . These findings suggested that we should consider the different working memory and executive function training targets to increase cognitive capacity of ASD and ADHD.

Enhancing treatment of osteoarthritis knee pain by boosting expectancy: A functional neuroimaging study.

Objectives: Expectation can significantly modulate pain and treatment effects. This study aims to investigate if boosting patients' expectancy can enhance the treatment of knee osteoarthritis (KOA), and its underlying brain mechanism. Methods: Seventy-four KOA patients were recruited and randomized to three groups: boosted acupuncture (with a manipulation to enhance expectation), standard acupuncture, or treatment as usual (TAU). Each patient underwent six treatments before being debriefed, and four additional treatments after being debriefed. The fMRI scans were applied during the first and sixth treatment sessions. Results: We found significantly decreased knee pain in the boosted acupuncture group compared to the standard acupuncture or TAU groups after both six and ten treatments. Resting state functional connectivity (rsFC) analyses using the nucleus accumbens (NAc) as the seed showed rsFC increases between the NAc and the medial prefrontal cortex (MPFC)/rostral anterior cingulate cortex (rACC) and dorsolateral prefrontal cortex in the boosted group as compared to the standard acupuncture group after multiple treatments. Expectancy scores after the first treatment were significantly associated with increased NAc-rACC/MPFC rsFC and decreased knee pain following treatment. Conclusions: Our study provides a novel method and mechanism for boosting the treatment of pain in patients with KOA. Our findings may shed light on enhancing outcomes of pharmacological and integrative medicines in clinical settings.

Frequency-dependent functional connectivity of the nucleus accumbens during continuous transcutaneous vagus nerve stimulation in major depressive disorder.

Transcutaneous vagus nerve stimulation (tVNS) may be a promising treatment for major depressive disorder (MDD). In this exploratory study, fMRI scans were acquired during continuous real or sham tVNS from 41 MDD patients. Then, all patients received real or sham tVNS treatment for four weeks. We investigated the functional connectivity (FC) of the nucleus accumbens (NAc) at different frequency bands during real and sham tVNS and explored their associations with depressive symptom changes after one month of treatment. The results revealed: 1) significant positive FCs between the NAc and surrounding areas including the putamen, caudate, and distinct areas of the medial prefrontal cortex (MPFC) and the anterior cingulate cortex (ACC) during continuous real and sham tVNS; 2) compared with sham tVNS, real tVNS increased the FC between the left NAc and bilateral MPFC/rACC in the slow-5 band (0.008-0.027) and between the right NAc and left insula, occipital gyrus, and right lingual/fusiform gyrum in the typical low band (0.008-0.09); and 3) the FC of the NAc-MPFC/rACC during real tVNS showed a negative association with Hamilton Depression Rating Scale (HAMD) score changes in the real tVNS group after one month of treatment, but not in the sham group. Our findings demonstrate that tVNS can modulate low frequency intrinsic FC among key brain regions involved in reward and motivation processing and provide insights into the brain mechanism underlying tVNS treatment of MDD.

Intrinsic Neural Linkage between Primary Visual Area and Default Mode Network in Human Brain: Evidence from Visual Mental Imagery.

Previous studies have reported the essence of the sensory-based properties of human brain function, in which mental imagery is of great importance. In this study, we explored the association between the activities of two special regions, i.e., the primary visual area (PVA), which is the classically dominant sensory region, and the default mode network (DMN), which is the classical supra-sensory region, with a focus on their linkage in visual mental imagery. For this purpose, we collected fMRI data from 30 healthy participants (15 males; 22.37 ±â€¯2.52 years) during the resting state and a mental rotation task state. By using a critical time point analysis (CTPA), we investigated the association between the activities of the PVA and the DMN. As the results showed, there existed a PVA-related (i.e., prefrontal cortex, DMN, sensorimotor areas and medial temporal lobe (MTL)) and a DMN-related neural association pattern (i.e., PVA, prefrontal cortex and the MTL) in the human brain. Furthermore, the results showed the steady and tight intrinsic association between the activities of the PVA and the DMN, with the prefrontal cortex and the MTL regions being found to be consistently involved in the resting-state brain. It also was suggested that the observed association between the PVA and the DMN was highly reproducible for the mental rotation task. Together, these observations, from the perspective of visual mental imagery, provided experimental evidence for the robustness and stability of the detailed map of the associations between the activities of the PVA and the DMN.